Sequestration and Activation of Small Gas Molecules on BN-Flakes

Subscriber access provided by UNIV TORONTO

Article

Sequestration and Activation of Small Gas Molecules on BNFlakes and the Effect of Various Metal Oxide Molecules therein Debdutta Chakraborty, and Pratim Kumar Chattaraj J. Phys. Chem. C, Just Accepted Manuscript • DOI: 10.1021/acs.jpcc.6b08404 • Publication Date (Web): 18 Nov 2016 Downloaded from http://pubs.acs.org on November 19, 2016

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

The Journal of Physical Chemistry C is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Physical Chemistry

Sequestration and Activation of Small Gas Molecules on BN-Flakes and the Effect of Various Metal Oxide Molecules therein Debdutta Chakraborty and Pratim Kumar Chattaraj* Department of Chemistry and Centre for Theoretical Studies Indian Institute of Technology, Kharagpur 721302, West Bengal, India *

To whom correspondence should be addressed. E-mail: [email protected], Telephone: +91 3222 283304, Fax: 91-3222-255303.

Abstract

The possibility of sequestrating gas molecules (H2, CO, NO, O3, H2O and O2) through pristine as well as metal oxide molecule (MO, M=Cu, Ag, Au) supported boron nitride flakes (BNF) has been investigated through density functional theory (DFT) based computations. Thermodynamic (at 298 K) as well as energetic criteria reveal reasonable stability of the MO@BNF moieties. Orbital and electrostatic interactions play crucial roles in stabilizing these systems. MO@BNF moieties, in general, can sequestrate some representative gas molecules, viz., H2, CO, NO, O3, H2O and O2 in a thermodynamically as well as energetically more facile way as compared to that on pristine BNF. In particular, reversible H2 storage might be feasible at ambient temperature and pressure through MO@BNF. NBO as well as AIM results indicate that the chosen gas molecules, in general, attain an ‘active’ state upon getting adsorbed on MO@BNF moieties as compared to their respective free counterparts.

1 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 2 of 46

1. Introduction The successful experimental characterization of graphene

1-2

ushered in a new era as far

as low dimensional materials are concerned. The exceptional physical as well as electronic properties of graphene enabled it to be considered in diverse applications such as nanoelectronics, optoelectronic devices, energy storage, biosensing, etc. to name a few. Schedin and co-workers

3

examined the sensitivity of graphene towards the

existence of various gas molecules and therefore graphene has been considered to be a major component as far as engineering new generation of sensors is concerned. Despite possessing many intriguing features, graphene has small density of states close to its Fermi level. Graphene also has zero band gap. As a consequence its even wider application in different domains gets severely constrained. All these recent developments have prompted theoreticians as well as experimentalists to explore the physical and electronic properties of other low dimensional materials which are structural analogues of graphene. At the forefront among them are the boron nitride materials which may exist in various geometrical conformations ranging from monolayer flakes or sheets to nanotubes 4-9

. Monolayer hexagonal boron nitride flakes (BNF) can be considered as an inorganic

analogue of monolayer graphene flake. However, due to the difference in electronegativity of the constituent atoms, BNF obtains a polar surface 10 as compared to graphene flake. The extended π electron network of graphene flake is not present in BNF (more localized π electron network) and the situation bears a qualitative resemblance to that present in benzene and its inorganic counterpart borazine. As a result BNF obtains a finite band gap unlike graphene. BNF can act as an electrical insulator and is resistant towards getting oxidized therefore enabling it to be used at very high temperatures. It has been shown that reducing the size of the flake can have profound impact on the electronic as well as magnetic properties of BNF 11-15. The chief reason for this could be attributed to the quantum confinement effects. Edge functionalization as well as an external electric field could also tune the electronic as well as magnetic properties of BNF. As a result of these, BNF could potentially be utilized in various different fields such as gas sensors, nanocomposites, spintronic devices, etc. Recently the gas sensing properties of BNF have been investigated in presence of guests such as O3, CO and CO2

16-18

. The adsorption behavior of several nucleobases, ionic liquids, amino 2 ACS Paragon Plus Environment

Page 3 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


acids on BNF

19-23

has also been studied. Molecular charge transfer interactions

12

involving BNF and chosen guest molecules could potentially modify the optical as well as electronic properties of BNF. BNF has large surface area and as a result has a great potential in acting as a gas sensor/sequestration material. Recent experimental reports suggest that BNF is less toxic 24 as compared to its structural analogue graphene therefore improving its suitability towards probable applications. An attractive route towards tuning the electronic properties and as a result controlling the response properties of nanomaterials derived from boron nitride flakes, is to functionalize BNF with some external chemical agents. However, the hexagonal BNF materials are fairly stable and are reluctant to getting chemically modified through functionalization. Nevertheless, various probable paths have been explored of late to chemically modify BNF materials. Noteworthy attempts in this regard involved functionalizing BNF with hydroxyl (-OH)

25

, alkyl (-R)

26

, amino (-NH2) 27, etc. groups. The effect of heteroatom

doping 28 has also been explored. Hybrid materials derived from ZnO 29, SnO2 30, TiO2 31, ZIF-8

32

etc. supported BNF proved to be some promising new developments. Details

regarding various other possible ways in functionalizing BNF could be found in reference 33. All these attempts proved to be quite fascinating as far as tailoring various properties of BNF is concerned. It has been proposed that dispersed Cu2O octahedrons supported on BNF can act as an efficient reducing agent

34

. Keeping in mind these recent

developments, it is worthwhile to explore various other feasible routes towards functionalizing BNF as it may have a desirable impact on the applicability of BNF in various purposes. For an example, Takahashi and co-workers demonstrated that functionalization of BNF through small Fe clusters may enhance the H2 storage capacity of BNF

35

. Similar favorable outcome might be possible as far as adsorption of other

chemically/biologically important gas molecules on BNF is concerned. It is to be noted that H2 is among the best probable candidates for alternative fuel and various viable routes to adsorb H2 have been investigated

36-41

. Nevertheless the goal to

attain reversible H2 storage at ambient temperature and pressure remain illusive to a large extent. Pristine metal clusters interact with H2 too strongly thereby hindering the process of desorption whereas pristine monolayers of low-dimensional materials interact with H2 3 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 4 of 46

typically through a physisorption pathway thereby limiting the H2 uptake capacity. However, the situation could be improved significantly if the metals/metal clusters could be supported through some host material such as BNF. On the other hand, H2 can also take part on various heterogeneous catalytic cycles and thus adsorption of H2 on various surfaces has been studied with great vigor

42

. Essential prerequisite for its catalytic

activity of course demands H2 to remain dissociatively bound to the surface thereby offering a source of labile H atoms. CO, NO and O3 are among the potentially hazardous gases present in earths atmosphere and finding a suitable adsorbent is of significance 43-47. H2O on the other hand is omnipresent in different chemical/biological processes. Gaining fundamental understanding of its binding with different hosts offer important insights which may have important consequences. It has been proposed that H2O can have a very important role in designing new generation of fuel cells

48-49

adsorption properties of O2 on different surfaces/molecules

. Understanding the 50-52

has important

technological consequences in different domains such as oxidation, catalysis, corrosion, etc. Extensive work has been carried out to find a suitable reversible O2 adsorbent 53 that may potentially mimic the efficiency of biological O2 adsorbents. To this end, low toxic materials such as BNF may provide an ideal platform. Considering all these factors, it is therefore worthwhile to explore the possibility of sequestrating the mentioned gas molecules with the help of pristine as well as functionalized BNF. It is also important to understand the changes imparted on the nature of bonding of the said gas molecules when they get adsorbed on some substrate such as BNF and detailed theoretical analysis in this regard deserves attention. In this work, we seek to investigate whether the gas sequestration properties of BNF could be improved if the host moiety is functionalized with transition metal oxide molecules

54-56

(MO, where M=Cu, Ag and Au). It is a well known fact that MO

molecules could be utilized in a vast array of applications primarily due to the presence of highly ‘activated’ metal centers. The probable applications nonetheless become somewhat limited due to fact that these molecules upon getting synthesized tend to form clusters thereby losing the desirable metal coordination site. Therefore, it is prudent to explore the possibility of stabilizing the molecular form of MO molecules through some host and thereby retaining the desirable metal coordination sites of these molecules which 4 ACS Paragon Plus Environment

Page 5 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


may in turn could be of interest in various application purposes such as gas adsorption, catalysis etc. To this end, we have employed density functional theory (DFT) based calculations to assess the viability of adsorbing the chosen gas molecules through MO supported BNF. Detailed thermodynamic as well as energetic analysis has been carried out to ascertain the feasibility of the above stated processes. Further insights into the nature of interaction and bonding have been provided by carrying out Atoms-in aMolecule (AIM) and natural bond orbital (NBO) analyses as well as an energy decomposition analysis (EDA).

2. Computational Details We have modeled all the reported geometries with the help of graphical software GaussView 5.0.8

57

. A finite chunk of BNF with molecular formula B24N24H18 has been

considered as a model surface. All the end atoms of the model surface have been passivated with the aid of H atoms. Geometries of the concerned metal oxides, BNF and MO@BNF moieties have been optimized with the help of wb97xd functional

58

. The

metal atoms, viz. Cu, Ag and Au have been treated through a Stuttgart/Dresden (SDD) basis set keeping in mind the relativistic effects for the concerned atoms and SDD based effective core potentials (ECP) have been used. All the other atoms have been treated with the help of 6-311G(d,p) basis set. For all the MO molecules, we have considered the doublet spin states

54-56

as they constitute the ground electronic state. All the reported

geometries correspond to minima on their concerned potential energy surfaces as all the harmonic vibrational frequencies were found to be real numbers (NIMAG=0). No constraint has been added while performing the geometry optimization calculations. It is worth noting at this point, that the chosen functional comprises long range correlation corrections thereby enabling it to take care of dispersion effects, which may have some role to play in the present study. Detailed benchmarking studies carried out by Grimme and co-workers validate the reliability

59

of wb97xd functional. In order to ascertain the

extent of charge generated/depleted on each atomic center, we have carried out NBO analysis. The nature of interaction in between two atom centers has been characterized with the help of concerned Wiberg bond index (WBI). The donor-acceptor type 5 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 6 of 46

interactions pertaining to MO@BNF, can be qualitatively gauged with the aid of secondorder perturbation estimates in the NBO basis. In order to do this, one may consider all probable interactions in between the donor and acceptor NBOs from which their energetic contributions can be evaluated with the help of second order perturbation theory. The stabilization energy E(2) corresponding to the delocalization (i to j) is evaluated as (where donor NBO is designated as i and acceptor NBO is designated as j):

E(2)= ∆Eij = qi

F (i, j ) 2 ε j − εi

(1)

Here F(i,j) is off-diagonal NBO Fock matrix component, qi is the occupancy of the donor orbital, ε i and ε j are diagonal elements (orbital energy). Polarizability

60

(α) has

been computed according to the expression:

α=

1 (α xx + α yy + α zz ) 3

(2)

where αxx/yy/zz are the diagonal elements of the polarizability tensor. All the above mentioned computations have been performed with the help of Gaussian 09 program package

61

. In order to examine the nature of binding of the MO moieties with the host

BNF surface, we have carried out electron density analysis based on AIM theory

62-63

with the help of Multiwfn software 64. We have also considered the total density of states (TDOS) of the studied systems. The overlap density of states (OPDOS) has been presented therein. To this end, a Lorentzian broadening function has been used. Even though a basis set sensitive Mulliken population analysis scheme has been utilized to plot the TDOS/OPDOS (Multiwfn software has been utilized), such plots can provide us with helpful physical information with regard to distribution of different energy levels, both virtual as well as occupied. The EDA has been carried out through the ADF software 65 at the rev-PBE-D3/TZ2P level of theory by taking MO as one fragment and host BNF as another fragment. Keeping in mind the relativistic effects of the transition metal atoms, zero order regular approximation (ZORA) has been utilized while performing EDA. Finally, in order to investigate the adsorption of the chosen guest molecules on


Page 7 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


BNF/MO@BNF, we have performed unconstrained geometry optimization at the same wb97xd/6-311G(d,p)/SDD level of theory as noted previously (NIMAG=0 in all reported cases). The NBO, EDA and AIM analyses carried out following the methodologies outlined above, demonstrate the salient features with regard to the nature of binding of the chosen guests on the host surface. For H2, CO, O3 and H2O singlet spin states of the guests have been considered whereas for NO and O2, a doublet and triplet spin states respectively, have been considered. In order to validate the suitability of the aforementioned gas sequestration processes through MO@BNF, we have also considered the corresponding gas adsorption through a representative metal cluster (CuO)2

66

supported

by BNF. The level of theories as well as the optimization procedure (unconstrained) employed is same as before.

3. Results and Discussion 3.1 Thermodynamic viability of having MO@BNF complexes, their geometrical structures and electronic properties Let us firstly consider the minimum energy structure and the electron localization function (ELF) plot of BNF (Figure 1). Like graphene, the constituent atoms viz. B and N occupy a planar geometry in the case of BNF. However, the electron density distribution at the molecular plane of BNF is significantly different from that of its structural analogue graphene. Instead of an extended π delocalization, one may note a significant extent of localization of electron density centered on the N centers due to higher electronegativity. The B and N atoms are, however, covalently bonded as vindicated by the ELF plot. Upon introducing the MO molecules on the host surface (Figure 1), the host surface undergoes slight buckling. Primarily the B atoms of the host, that are closest to the incoming MO moieties, protrude beyond the host molecular framework. The O center of the MO moiety comes closer to the host surface than the metal centers. The corresponding distances of the O and M centers from the host framework have been presented in Table 1. The CuO moiety comes closest to the host surface as compared to its heavier counterparts. The CuO molecule aligns almost in a horizontal orientation with respect to the BNF surface whereas AgO and AuO molecules attain a slightly tilted orientation with respect to the BNF host. This particular conformation of the MO@BNF 7 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 8 of 46

moieties seems to be a favorable orientation as it could possibly maximize the interaction in between the host and the various atom centers of the guests. It should be noted that the MO molecules may bind with BNF through various other orientations. Since an unconstrained geometry optimization has been performed, we have only considered the present results for subsequent analyses. The suitability of the obtained geometries is verified by the presence of local minima on the concerned potential energy surfaces. Considering the thermochemical results (Table 1) in order to asses the feasibility of the MO binding ability of the BNF surface, one may note that CuO/AgO binds with BNF in a thermodynamically spontaneous way (negative Gibbs’ free energy changes (∆G)). The corresponding binding processes are exothermic in nature as vindicated by changes in enthalpy (∆H). AuO, however, binds with BNF in a thermodynamically non-spontaneous fashion despite the fact that the associated ∆H is negative. The above noted trend suggests that CuO is more suitable for forming a complex with BNF as compared to its heavier counterparts AgO and AuO. The zero point energy corrected dissociation energies (D0) suggest that all the MO molecules bind with BNF in an attractive way. In order to examine the size effect of BNF in binding with MO molecules, we have considered a bigger BNF moiety having molecular formula B54N54H28 as a representative test case (Figure S1). The relevant thermochemical as well as energetic results of the binding of CuO and AgO with B54N54H28 have been presented in Table S1 and the results are fairly consistent with the corresponding binding of CuO and AgO with B24N24H18. Interestingly, two CuO/AgO molecules also bind with B54N54H28 in a thermodynamically favorable manner thereby indicating that it might be possible to functionalize BNF with multiple MO molecules. Even though a finite flake has been considered in this work, the obtained results should hold true (at least in a qualitative sense) even if a bigger flake is taken. The computed HOMO-LUMO gap and polarizability in the case of BNF are 10.14 eV and 416.09 a.u.3 The HOMO-LUMO gap and polarizability of the MO@BNF moieties have been presented in Table 1. In order to understand the changes incorporated in the distribution of the electronic energy levels, both occupied as well as virtual, of BNF as a consequence of functionalization we consider the TDOS plots (Figure S2). It is quite apparent that the position of the Fermi level (EF) of BNF exhibits very small variation upon introducing MO molecules. One may note a small increase as far as the 8 ACS Paragon Plus Environment

Page 9 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


density of states near the Fermi level is concerned in the cases of MO@BNF as compared to BNF. All the MO molecules enable the host to gain a greater concentration of occupied electronic energy levels in an approximate energy window of -13.61 to -10.88 eV as compared to pristine BNF. The corresponding OPDOS values in the case of CuO@BNF suggest that the binding of CuO with BNF is favorable in an approximate energy window of ~ -21.77 to -12.5 eV beyond which the binding becomes unfavorable. For AgO@BNF, the binding in between AgO and BNF becomes favorable over an energy range ~ -21.77 to -13.61 eV whereas for AuO@BNF, the favorable energy window for binding decreases slightly. The observed results indicate that CuO is more suitable to bind with BNF as it can interact with the host over a slightly greater energy window.

3.2 NBO Analysis of the MO@BNF moieties In order to decipher the extent as well as principal direction of charge transfer occurring within the formed complexes, we now consider the results obtained from NBO analysis (Table 1). At the free states, the computed NBO charges on each atom centers of CuO, AgO and AuO are as follow; |0.81|, |0.61| and |0.45| e− respectively. The corresponding NBO charges on these metal oxides upon binding with BNF have been presented in Table 1. In all the cases, the metal centers acquire more positive charge on them as compared to their respective free states. These positively charged metal centers should play an important role in adsorbing some external gas molecules. In order to gain an insight into the direction of charge transfer in between the host and guest fragments, we now consider the E(2) (Table 1) values. We have only presented the dominant donor-acceptor type interaction from an energetic point of view occurring in between the MO and BNF segments of the system. In the case of CuO@BNF, lone pair orbital (LP) of N center of the surface donates electron density to the O center of the guest. Here the anti-bonding lone pair orbital (LP*) acts as a receptor of electron density. In the case of AgO@BNF, however, the LP* orbital of Ag center acts as principal acceptor of electron density whereas the anti-bonding (BD*B-N) orbital of the host acts as a donor. LP orbital of N center of the host donates electron density to the BD* orbital formed in between B and O atoms, in the case of AuO@BNF. It is quite apparent that geometrical proximity as well as suitable orientation dictates the outcome of the above noted charge transfer processes. CuO, being more closely situated to the host in its minimum energy configuration, is 9 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 10 of 46

more suited to take part in donor-acceptor type of interactions with the host as compared to its heavier analogues. Nonetheless, all the MO molecules interact with BNF in a fairly significant manner as vindicated by the magnitude of E(2) values. The concerned WBI values (Table 1) in between O and M centers of MO and the host surface indicate that the O center of the MO molecules binds with the B center of the BNF, in a strong manner. The situation is reminiscent of covalent bonds. The M centers of MO, however, interact with BNF in a weak fashion, as in non-covalent interactions. The strength of interaction in between M centers and N center of the host gradually decrease as we move from Cu to Au. The natural electronic configurations of the MO fragments may provide some qualitative rationale behind this observation (Table S2). The valence shell orbitals of Cu namely 4s/4p/3d are more favorable to interact with valence shell orbitals of B/N centers of the host from an energetic point of view as compared to its heavier analogous viz., Ag/Au which obviously interacts through valence shell orbitals having higher principal quantum number. This factor may also dictate the outcome of the observed thermochemical trends. One may also argue that since CuO is more polar (vindicated by the net separation of charges on positive and negative centers) in its pristine form than AgO/AuO, it finds it easier to interact with BNF. Considering the natural electronic configurations of the MO moieties in the BNF states, we may clearly infer that the valence shell orbital populations of the said fragments undergo significant changes as compared to their free counterparts. Clearly, electron density gets shifted from the M-O bond axis to the O-B as well as M-N bond axes and as a result we obtain the observed features.

3.3 AIM Analysis of the MO@BNF complexes In order to have a further understanding of the nature of binding occurring in between the MO and BNF moieties we now consider the AIM theory based results (Table 2). At this point it is essential to state a few of the chief features of the AIM theory 62-63. In general the magnitude of electron density (ρ(rc)) around a concerned bond critical point (BCP) as well as the sign of the Laplacian (∇2ρ(rc)) of electron density dictate whether a particular bond could be classified as covalent or non-covalent. However, these two conditions fail to justify the nature of binding in some known covalent molecules (such as CO, F2 etc.) and as a result one needs to consider additional descriptors to correctly describe a 10 ACS Paragon Plus Environment

Page 11 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


concerned mode of interaction. The principal descriptors in this regard are the local potential energy density (V(rc)) and local kinetic energy density (G(rc)). If the nature of binding is of covalent type, then stabilizing V(rc) should dominate over the contribution from the destabilizing G(rc) around a particular BCP. Therefore the summation of V(rc) and G(rc), which is known as the local electron energy density (H(rc)), should be a negative number for a covalent bond. The ratio of G(rc) and V(rc) is another useful descriptor and in general if its value is smaller than 1, then the corresponding bonding may be classified as having some degree of covalent character. The ELF is another important electron density descriptor and for a covalent bond its value could provide some conclusive evidence. With this background in mind, we consider the results obtained from AIM analysis for some representative BCPs present in between MO and BNF. The O-B BCPs in all the MO@BNF cases, bear some extent of covalent character by considering the H(rc), -G(rc)/V(rc) and ELF values. The metal centers nevertheless interact with host surface in a non-covalent fashion. The strength of interaction in between M-N atom centers decrease as we move from CuO to AuO as vindicated by considering the values of ρ(rc) as well as ELF around the M-N BCPs.

3.4 Energy Decomposition Analysis of the MO@BNF moieties To discern the nature of interaction in between MO and BNF segments of the formed complexes, we now consider the EDA results (Table 3). Here the total interaction energy (∆Etot) in between the concerned moieties has been decomposed into various fragments, which influence the overall interaction picture through various stabilizing as well as destabilizing factors. Herein, the ∆Etot comprises following components viz. electrostatic (∆Eel), orbital (∆Eorb), dispersion (∆Edisp) and Pauli repulsion (∆EPauli) energies. The first three components bear a stabilizing influence on the nature of binding whereas Pauli repulsion component destabilizes the system as a result of the presence of electrons in close proximity of one another as a result of bonding. It becomes quite evident that all the MO molecules bind with BNF in an attractive way. The ∆Eorb and ∆Eel play the major stabilizing roles as far as binding is concerned with minor stabilizing influence exerted by ∆Edisp. The greater role of ∆Eorb in the above mentioned scenario could easily be correlated with the NBO as well as AIM results which suggest that MO and BNF interaction bear some extent of covalent character. The contribution from ∆Eel could also 11 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 12 of 46

be justified on the basis of generation of oppositely charged atomic centers as a result of binding of MO and BNF. It is to be noted that magnitude of destabilizing contribution from ∆EPauli generally reduces in going from CuO@BNF to AuO@BNF. It could be argued that since the distance in between MO and BNF generally increases in going from CuO to AuO, the intervening electrons gain some more space to accommodate and as a result the ∆EPauli decreases. Similar point may hold true as far as the trends in ∆Eel are considered. Since the metal center Cu interacts with N center of the host to a slightly greater extent as compared to its heavier counterparts, we note a greater contribution arising from ∆Edisp towards the overall bonding situation for the cases of AgO/AuO@BNF. The important point to note here is that all the MO moieties interact with BNF in a favorable way which may serve as an important indicator towards the stability of the MO@BNF complexes.

3.5 MO@BNF moieties as gas sequestration materials: thermodynamic, geometric and electronic properties Based on the above mentioned discussion one may argue that the MO@BNF systems are reasonably stable. We now discuss the adsorption of the selected guest molecules on MO@BNF (Figures 2-5). For having a suitable reference, we shall also take into account the interaction of the guest molecules with pristine BNF. In the cases of CO/NO/O2/H2O/H2/O3 adsorption on BNF, all the processes are thermodynamically unfavorable (positive ∆G) despite the fact that in all the cases the corresponding adsorption processes are having negative ∆H (Table 4) associated with it. On the other hand, the corresponding adsorption situation in the cases of MO@BNF shows a noted improvement. Except for the cases of NO adsorption on CuO/AgO@BNF, in all other cases the adsorption processes become thermodynamically more favorable as compared to adsorption on BNF. Barring the NO adsorption processes on the mentioned hosts, all other adsorption processes are having a more favorable change in enthalpy than that of pristine BNF. D0 values indicate that the guests can interact with the MO@BNF moieties in a more favorable way than pristine BNF. Moreover, the D0 values in the cases of H2 adsorption are somewhere in between that of physisorption and chemisorption which will allow us to have a facile adsorption/desorption process that in turn will presumably provide us with a suitable reversible hydrogen storage material

35-41

to solve a two12

ACS Paragon Plus Environment

Page 13 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


pronged problem involving energy and environment. Similar arguments remain valid as far as O2 sequestration is concerned. These observations clearly point out that functionalized BNF is more suited to sequestrate the chosen guest molecules, in general, by virtue of being able to interact with the guest molecules in a more facile way. In general, H2O/O3 molecules show stronger tendencies to bind with CuO/AgO@BNF whereas AuO@BNF interacts with all the guests to a slightly greater extent as compared to its lighter congeners (as revealed by D0 values). In order to examine how would the adsorption pattern change if we consider gas molecules (particularly O2/NO) having a different spin state than the cases considered herein (i.e. triplet and doublet for O2 and NO respectively), we now consider (Table S5) the singlet and quartet spin states of O2 and NO molecules (designated as O2* and NO* respectively all throughout the manuscript). Results (Figures S3, S4) indicate that O2* and NO* bind with MO@BNF in a much more favorable way than O2 and NO. It is rather along expected line of thought since O2* and NO* should be more reactive than O2 and NO. In concomitance with earlier trends we may state that MO@BNF moieties can sequestrate the chosen molecules in a better way than BNF except for the case of NO* adsorption on AgO@BNF. One may also note that the adsorption of NO* on BNF is fairly strong as indicated by D0/∆G/∆H values. All the guest molecules remain at a fair distance apart from the host pristine BNF surface at the minimum energy structure. As a result of adsorption, the structural changes imparted on the host surface are negligibly small. In the gas sequestration cases on MO@BNF, a noteworthy decrease in the host-guest distances is noted (Table 5). It is to be noted that in presence of the guests, the structure of the host should not get disrupted too much as it could adversely affect the stability of the host. In all the cases of adsorption, the average M-N and O-B distances do not show a major change thereby affirming the fact that the MO@BNF moieties in presence of guests do not get adversely affected as far as stability is concerned. The extent of distortion incurred upon the BNF surface of the MO@BNF complexes due to gas adsorption is also small. Considering the bond lengths of the guest molecules at the adsorbed state, we may infer that in the cases of pristine BNF, the guests undergo negligibly small variation in their bond lengths as compared to their corresponding free states. In the case of gas adsorption on CuO@BNF, we note that except for the case of CO adsorption, in all other cases the bond lengths of 13 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 14 of 46

the guests (viz. NO, O2, H2O, H2 and O3) undergo some extent of lengthening as compared to their free states (Tables S3 and S4). One may infer, in a qualitative sense, that the mentioned guest molecules at the adsorbed state on CuO@BNF attain a slightly ‘active’ state. In the case of AgO@BNF, CO and O2 exhibit minor variation upon getting adsorbed. H2O, H2 and O3, however, undergo a lengthening in their respective bond lengths. Bond length of NO molecule decreases upon adsorption marking a significant deviation from the above noted trend. In the case of AuO@BNF, except for the cases of CO and O2 adsorption, all other guests undergo some changes in their bond lengths. These results highlight that one may at least in a qualitative sense obtain the concerned guests in a slightly ‘active’ state when they get attached to the MO@BNF moieties which one may exploit in their catalytic activities. O2* upon getting adsorbed on the hosts MO@BNF undergo a lengthening of the O-O bond, however, except for the case of AgO@BNF, N-O bond of NO* shortens upon getting adsorbed. We now consider the changes in electronic properties incurred upon BNF/MO@BNF moieties as a result of gas adsorption (Table 4). As a result of CO/H2O/H2 adsorption on BNF, the HOMOLUMO gap of the host does not change much. Adsorption of NO/O2 molecules changes HOMO-LUMO gap of the host to some extent. O3 molecule, however, lowers the HOMO-LUMO gap of the BNF moiety to a significant extent. Variations in polarizability in all these cases are small. O3@BNF among all these cases exhibits the highest α value. Among the gas adsorption cases on CuO@BNF, NO/O2/O3 changes the electronic properties of the host to the most extent and like the previous case O3 plays the dominant role for this purpose. Similar observations are noted in the cases of AgO/AuO@BNF as well. As far as the TDOS and OPDOS plots (Figures S5-S14) are concerned for the guest@BNF complexes, we note that all the guests interact with the host through a small energy window. In all the cases EF shows a minor variation in its position. In all the cases of gas adsorption on MO@BNF, the OPDOS values indicate that the guests bind with the hosts through a greater energy window therefore making the corresponding binding processes more favorable as compared to the similar situation in the case of pristine BNF. NO/O3/O2 molecules upon getting adsorbed on pristine BNF, enhances the overall concentration of energy levels of the host. However, the presence of H2/H2O molecules has very small influence on the density of electronic states of the host. Similar 14 ACS Paragon Plus Environment

Page 15 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


observation is noted in the cases of CuO/AgO/AuO@BNF as well. CO molecule influences the electronic properties of AuO@BNF to a certain extent although in all other cases it fails to modulate the electronic properties of the host complex to a significant extent.

3.6 NBO analysis of the CO/NO/H2/H2O/O2/O3@MOBNF/BNF moieties In order to elucidate the nature of charge transfer taking place within the studied adsorption processes, we consider the results obtained from NBO analysis (Table 5). In the case of gas adsorption processes on pristine BNF, the extent of change occurring in between the guests and the host is small and as a result the NBO charges on the various adsorbate atomic centers show minor variation as compared to their respective free states (Table S4). The associated WBI values concerning the various bonds present within the adsorbates suggest that the mode of binding change very little upon getting adsorbed on BNF. In general the BD*B-N/ LP*B orbitals of the host act as receptors of electron density from the various guests. In the case of H2 adsorption, however, the bonding orbital (BD) centered in between B and N atoms gives electron density to the anti-bonding orbital formed in between the incoming H atoms. The scenario changes significantly when we take into account the corresponding adsorption processes on functionalized BNF moieties. The NBO charges on different atom centers of the adsorbates exhibit a marked deviation from that present in their free states. Let us consider the cases of gas adsorption on CuO@BNF. CO molecule donates electron density through its O center to the Cu atomic center of the host. As a result of this charge transfer, WBI value of CO bond decreases as compared to its free state. Similar situation prevails in the cases of NO/O2/H2O/H2/O3 adsorption as well. As a result the bonds of NO/O2/H2O/H2/O3 molecules at the adsorbed state weaken considerably as vindicated by the corresponding WBI values. In all these cases, the positively charged Cu center of the host being geometrically closer to the incoming guest molecules plays the pivotal role in dictating the extent of charge transfer. As a result of this, the NBO charges on the Cu and O atom centers of the host undergo some changes as compared to the parent moiety. Except for the case of NO adsorption, in all other cases the NBO charge on Cu center diminishes. As a result the net separation of charges on Cu and O centers reduce in all the cases thereby 15 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 16 of 46

making them slightly less polar, but for the case of NO adsorption. For the corresponding adsorption scenario, in the case of AgO@BNF, similar qualitative features are noted except for the case of NO adsorption. In the cases of CO/O2/H2O/H2/O3 adsorption, the corresponding bonds of the adsorbates weaken as compared to their respective free states (verified by the WBI values). The reason for this could be understood on the basis of the E(2) values. For the cases of CO/O2/H2O/O3 adsorptions, the LP orbital of O of the adsorbates donates electron density to the LP* orbital of the Ag center of the host. For the case of H2 adsorption, however, the BD orbital formed in between the H atoms plays the role of donor of electron density wherein LP* orbital of Ag acts as receptor. In the case of NO adsorption, however, the O center of AgO@BNF, donates electron density through its LP orbital to the BD* orbital of the adsorbate. As a result a significant chunk of electron density gets transferred to the N-O bond axis which may provide a rationale for the fact that in the case of NO adsorption, the WBI value of the N-O bond of the adsorbate increases thus exhibiting a deviation from the trends noted thus far. In all the cases of gas adsorption on AuO@BNF, the adsorbates undergo a significant weakening in their respective bond strengths upon getting adsorbed on AuO@BNF. In all the cases, the BD* orbitals of Au-O acts as a receptor of electron density from various atom centers of the guests except for the case of NO adsorption where the anti-bonding orbital formed in between Au and N centers plays the role of receiver of electron density. In general, in most of the cases of gas adsorption on MO@BNF, the magnitudes of E(2) values indicate the possibility of existence of some degree of covalent character as far as the interaction in between the hosts and guests is concerned. The corresponding E(2) values in the cases of pristine BNF, however, are indicative of the fact that the host and the guests may interact through non-covalent pathways. O2* upon getting adsorbed undergoes significant weakening of the O-O bond as suggested by WBI (Table S6). NO*, however, exhibits a different behavior and at the adsorbed state, the WBI of N-O bond increases. The natural electronic configuration of the guests (Table S7) does not change much upon getting adsorbed on pristine BNF. However, a noteworthy change is noted as far as the corresponding situation in the cases of MO@BNF are concerned. The valence shell s and p orbitals (such as 1s/2s/2p) of the guests mainly take part in interaction with the host


Page 17 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


molecular framework with minor contributions coming from the orbitals having higher energy (such as 3s/3p/3d).

3.7 Nature of binding of CO/NO/H2/H2O/O2/O3@MOBNF/BNF moieties: AIM analysis In order to examine the nature of binding of the chosen guests with the various hosts under consideration in greater detail, we now consider the results obtained from AIM analysis (Table 6). All the guests bind with the pristine BNF surface in a non-covalent fashion as revealed by various electron density descriptors. The changes occurring within the various BCPs of the guests, upon getting adsorbed are small. The mode of binding of H2 and NO with CuO@BNF is having partially covalent character as suggested by various electron density descriptors. The other guests however interact with the host through non-covalent way. However, consideration of the ρ(rc) and ELF values centered on the concerned BCPs suggests that the mode of binding are far stronger than the corresponding situation in the cases of pristine BNF. These results are fairly consistent with the earlier observations noted from NBO analysis. Most importantly, the BCPs centered on the adsorbate molecules show important changes. For an example, the ρ(rc) values for the C-O, O-H, N-O, H-H, O-O, and O-O BCPs of the CO/H2O/NO/H2/O2/O3 molecules decrease (as compared to their free states) (Table S8) upon getting adsorbed on CuO@BNF. Therefore one may argue that the concentration of electron density around these BCPs reduce thereby indicating somewhat weakening of these bonds, at the adsorbed state. For the cases of AgO@BNF, H2 and O3 molecules bind with the host in a partially covalent way whereas other guests interact with the host framework in a noncovalent manner. Interestingly, at the bound state, the N-O BCP of the guest NO molecule gains some additional electron density therefore indicating that the host transfers some electron density on the said BCP. In all other cases, however, the guests lose some of its electron density as a result of interaction with the host molecule as suggested by the concerned electron density descriptors. In the case of AuO@BNF, all the guests except O2 interact with the host surface in a partially covalent way. General qualitative trends noted previously are also operative here. It is to be noted that in the presence of these gas molecules, the nature of binding of M-N/O-B BCPs of MO@BNF 17 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 18 of 46

moieties does not get adversely affected. In the cases of O2*, AgO/AuO@BNF interacts with the guest through partly covalent pathway whereas NO* does so in all the cases including that of BNF (Table S9). The ρ(rc) values around O-O/N-O bonds suggest that in presence of MO@BNF, the O-O bonds weaken to some extent whereas the N-O bond does so while interacting with AgO@BNF. In all other cases, the N-O bonds acquire some additional concentration of electron densities.

3.8 Energy Decomposition Analysis of the CO/NO/H2/H2O/O2/O3@MOBNF/BNF moieties Considering the EDA results (Table 7), one may note that all the chosen guests interact with pristine BNF in an attractive manner. Herein, the contribution from ∆Edisp plays the dominant role in stabilizing the concerned moieties. This is fairly consistent with the results obtained from NBO as well as AIM analyses. In the cases of gas adsorption on CuO@BNF, ∆Eel and ∆Eorb exert the major stabilizing influence with a minor contribution coming from ∆Edisp. The ∆Etot values clearly demonstrate the greater stability of these systems as compared to the gas adsorption cases on pristine BNF. We have seen through NBO analysis that processes like charge transfer and polarization are playing critical roles in these adsorption processes. Therefore, the contribution from ∆Eorb could be justified on the basis of these facts. Similarly, presence of oppositely charged atomic centers within close geometrical proximity allows electrostatic interactions to enact a major role in stabilizing the concerned systems. Qualitatively similar trends are noted as far as the gas adsorption processes on AgO/AuO@BNF are concerned. Particularly noteworthy are the interactions in between NO and MO@BNF moieties where major stabilizing influence comes from ∆Eorb. We may infer based on the NBO as well as AIM results that NO molecule undergoes a significant extent of change upon binding with MO@BNF moieties. Significant extents of electron density get transferred from the NO molecule to the CuO/AuO@BNF moieties. Reverse trend is noted in the corresponding case of AgO@BNF. All these electron density shift processes involve a significant participation by the intervening orbitals. This may provide some rationale behind the above noted trends. CuO@BNF exhibits greater preference in adsorbing H2O, O3 and NO molecules as revealed by the ∆Etot values. Similar tendency is exhibited by AgO@BNF as well. AuO@BNF, however, in addition to the fairly strong interactions 18 ACS Paragon Plus Environment

Page 19 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


with H2O, O3 and NO, interacts with CO and H2 molecules with much greater strength as compared to CuO/AgO@BNF moieties. Comparing the ∆Etot values, we may conclude by stating that AuO@BNF is more suited to sequestrate the chosen gas molecules than its lighter congeners. This observation could also be validated by considering the thermochemical results. O2*/NO* interacts with the concerned hosts to a greater extent as compared to O2/NO and these findings are consistent with other results discussed before (Table S10).

3.9 Can (CuO)2@BNF sequestrate the concerned gas molecules? A representative test study We have seen that functionalization of BNF with the aid of MO molecules can have a desirable impact on the gas sequestration properties of the host. In order to verify whether a metal cluster composed of the considered metal oxides, can have analogous effect on the gas adsorption capability of BNF, we now consider (CuO)2 66 supported BNF moiety (Figures 6, S15-S16). Thermochemical results (Table 1) indicate that (CuO)2 can form a complex with BNF in a spontaneous and energetically favorable fashion. Moreover, the WBI (Table 1) values and AIM results (Table 2) indicate that the O/Cu centers of the metal cluster interact with the host in a fairly similar way as does CuO. As in the case of CuO@BNF, here also the Cu centers have some positive charges on them which in turn should act as a favorable anchoring site for various gas molecules. EDA results (Table 3) provide further confirmation of the fact that the concerned metal cluster can interact with the host in a facile way and ∆Eel and ∆Eorb provide the maximum stabilizing influence to this end. Let us now consider the gas sequestration capability of (CuO)2@BNF. All the thermochemical indicators (changes in ∆G, ∆H) point out that (CuO)2@BNF can adsorb the chosen gas molecules in a more favorable way as compared to pristine BNF (Table 4). D0 values highlight that all the gas molecules interact with the (CuO)2@BNF moiety in an attractive fashion and the situation is fairly consistent with the results obtained in the corresponding cases of CuO@BNF. Of particular interest are the cases of H2/O2 adsorption wherein D0 values fall within the range of reversible storage criterion. Consideration of WBI values (Table 5) of the various bonds of the adsorbates at the adsorbed state indicate that (CuO)2@BNF can activate H2/O2/O3/H2O molecules although 19 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 20 of 46

the said effect is marginal in the cases of CO/NO molecules. Interestingly as a result of gas adsorption, the structure of the host undergoes minor deviation as vindicated by OB/Cu-N bond lengths (Table 5). AIM results (Table 6) indicate that CO/NO/H2/O3 molecules interact with (CuO)2@BNF in a partly covalent way whereas O2/H2O molecules do so in a non-covalent manner. Moreover, consideration of the various AIM based electron density descriptors demonstrate that H2/O2/H2O/O3 molecules upon getting adsorbed on (CuO)2@BNF obtain a slightly active state since the corresponding bonds of the said adsorbates weaken to a certain extent. The said effect is small as far as adsorption of CO/NO are concerned. EDA results (Table 7) indicate that the concerned gas molecules interact with the host favorably and as in the corresponding cases of CuO@BNF, here also, ∆Eel and ∆Eorb exhibit the maximum stabilizing influence. One may state based on the above discussion that the general qualitative trends noted in the cases of CuO@BNF hold true even if a metal cluster such as (CuO)2 is considered to functionalize BNF and this may help the host to act as a better gas adsorbing material.

4. Conclusions In this work we have investigated the gas sequestration properties of BNF and whether the gas sequestration capability of BNF could be improved upon functionalization, through DFT based calculations. For this purpose we have functionalized the host BNF with some transition metal oxide molecules (MO, where M=Cu, Ag and Au). Thermochemical as well as energetic results indicate that as a consequence of functionalization, the gas (H2/O2/O3/NO/CO/H2O) sequestration capability of BNF could be significantly improved at 298 K temperature and one atmosphere pressure. In its pristine form, BNF cannot adsorb the concerned gases to the desired extent. However, once functionalized with the MO molecules, the host can sequestrate the concerned gases effectively by virtue of utilizing the ‘active’ metal centers which enact the role of a favorable anchoring site for the gas molecules and can polarize the incoming gas molecules sufficiently so that a favorable binding takes place. EDA results highlight the detailed mechanism through which the gases interact with the hosts. Pristine BNF interacts with the said gases mainly through weak dispersion interactions whereas MO@BNF utilizes fairly strong orbital and electrostatic interactions to sequestrate the 20 ACS Paragon Plus Environment

Page 21 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


gas molecules. Consideration of NBO as well as AIM results indicates that the chosen guest molecules attain, in general, a more ‘reactive’ state at the adsorbed state on MO@BNF as compared to their respective free counterparts. All the adsorbates, however, retain their molecular forms at the adsorbed state. AuO@BNF exhibits greater tendency to sequestrate the gas molecules than CuO/AgO@BNF. Importantly, consideration of D0 values indicate that MO@BNF can adsorb H2/O2 molecules in a desirable way that may facilitate favorable adsorption/desorption processes at ambient temperature and pressure (which is not feasible with the help of pristine BNF). We have also demonstrated that a representative metal cluster (CuO)2 supported BNF, can also act as an efficient gas sequestration material. Given the fact that MO molecules bind with BNF in a thermodynamically/energetically favorable way, the said pathway of functionalizing BNF could be of interest. It has also been demonstrated by taking a test case that two CuO/AgO molecules can bind with BNF in a suitable way thereby indicating that functionalization at multiple sites of the host BNF might be feasible. BNF possesses some inherent qualities as an efficient gas adsorbing/storing material such as low molecular weight as compared to many other metal-organic frameworks, non-toxic nature, high surface area, high mechanical resistance, etc. The present study highlights the efficacy of functionalizing BNF through covalent pathway which may result in an enhancement in the efficiency of BNF to act as an improved gas sequestrating material.

Acknowledgements DC thanks CSIR, New Delhi for the financial assistance. PKC would like to thank DST, New Delhi for the J. C. Bose National Fellowship.

Supporting Information Available Thermochemical data for binding of CuO/AgO/2(CuO/AgO) with B54N54H28, natural electronic configurations of some selected atom centers in MO/(CuO)2@BNF complexes, the bond lengths of the adsorbates at the adsorbed states, NBO/AIM results for the free gas molecules, thermochemical, NBO, AIM and EDA results for binding of NO*/O2* with MO@BNF/BNF, natural electronic configurations of selected atom centers of 21 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 22 of 46

adsorbate@MOBNF/BNF/(CuO)2@BNF complexes, the corresponding minimum energy structures as well as TDOS plots are presented. This material is available free of charge via the Internet at http://pubs.acs.org.

References (1) Novoselov, K. S.; Geim, A. K.; Morozov, S. V.; Jiang, D.; Zhang, Y.; Dubonos, S. V.; Grigorieva, I. V.; Firsov, A. A. Electric Field Effect in Atomically Thin Carbon Films. Science. 2004, 306, 666−669. (2) Novoselov, K. S.; Geim, A. K.; Morozov, S. V.; Jiang, D.; Katsnelson M. I.; Grigorieva, I. V.; Dubonos S. V.; Firsov A. A. Two-dimensional Gas of Massless Dirac Fermions in Graphene. Nature. 2005, 438, 197-200. (3) Schedin, F.; Geim, A. K.; Morozov, S. V.; Hill, E. W.; Blake, P.; Katsnelson, M. I.; Novoselov, K. S. Detection of Individual Gas Molecules Adsorbed on Graphene. Nat. Mater., 2007, 6, 652-655. (4) Shi, Y. M.; Hamsen, C.; Jia, X. T.; Kim, K. K.; Reina, A.; Hofmann, M.; Hsu, A. L.; Zhang, K.; Li, H. N.; Juang, Z. Y.; et al. Synthesis of Few-Layer Hexagonal Boron Nitride Thin Film by Chemical Vapor Deposition. Nano Lett. 2010, 10, 4134−4139. (5) Song, L.; Ci, L. J.; Lu, H.; Sorokin, P. B.; Jin, C. H.; Ni, J.; Kvashnin, A. G.; Kvashnin, D. G.; Lou, J.; Yakobson, B. I.; et al. Large Scale Growth and Characterization of Atomic Hexagonal Boron Nitride Layers. Nano Lett. 2010, 10, 3209−3215. (6) Zeng, H. B.; Zhi, C. Y.; Zhang, Z. H.; Wei, X. L.; Wang, X. B.; Guo, W. L.; Bando, Y.; Golberg, D. “White Graphenes”: Boron Nitride Nanoribbons via Boron Nitride Nanotube Unwrapping. Nano Lett. 2010, 10, 5049−5055. (7) Golberg, D.; Bando, Y.; Huang, Y.; Terao, T.; Mitome, M.; Tang, C.; Zhi, C. Boron Nitride Nanotubes and Nanosheets. ACS Nano. 2010, 4, 2979−2993. (8) Sutter, P.; Lahiri, J.; Albrecht, P.; Sutter, E. Chemical Vapor Deposition and Etching of HighQuality Monolayer Hexagonal Boron Nitride Films. ACS Nano. 2011, 5, 7303−7309.


Page 23 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(9) Chopra, N. G.; Luyken, R. J.; Cherrey, K.; Crespi, V. H.; Cohen, M. L.; Louie, S. G.; Zettl, A. Boron Nitride Nanotubes. Science. 1995, 269, 966−967. (10) Pakdel, A.; Zhi, C.; Bando, Y.; Golberg, D. Low-Dimensional Boron Nitride Nanomaterials. Mater. Today. 2012, 15, 256–265. (11) Du, A.; Chen, Y.; Zhu, Z.; Amal, R.; Lu, G. Q.; Smith, S. C. Dots Versus Antidots: Computational Exploration of Structure, Magnetism, and Half-Metallicity in Boron−Nitride Nanostructures. J. Am. Chem. Soc. 2009, 131, 17354−17359. (12) Bandyopadhyay, A.; Yamijala, S. S. R. K. C.; Pati, S. K. Tuning the Electronic and Optical Properties of Graphene and Boron-Nitride Quantum Dots by Molecular Charge-Transfer Interactions: a Theoretical Study. Phys. Chem. Chem. Phys. 2013, 15, 13881−13887. (13) Yamijala, S. S. R. K. C.; Bandyopadhyay, A.; Pati, S. K. Structural Stability, Electronic, Magnetic, and Optical Properties of Rectangular Graphene and Boron Nitride Quantum Dots: Effects of Size, Substitution, and Electric Field. J. Phys. Chem. C. 2013, 117, 23295−23304. (14) Neek-Amal, M.; Beheshtian, J.; Sadeghi, A.; Michel, K. H.; Peeters, F. M. Boron Nitride Monolayer: A Strain-Tunable Nanosensor. J. Phys. Chem. C. 2013, 117, 13261−13267. (15) Yamijala, S. S. R. K. C.; Bandyopadhyay, A.; Pati, S. K. Electronic Properties of Zigzag, Armchair and Their Hybrid Quantum Dots of Graphene and Boron-Nitride With and Without Substitution: A DFT Study. Chem. Phys. Lett. 2014, 603, 28−32. (16) Anota, E. C.; Cocoletzi, H. H.; Rosas, E. R. LDA Approximation Based Analysis of the Adsorption of O3 by Boron Nitride Sheet. Eur.Phys. J. D. 2011, 63, 271−273. (17) Zhang, Y. H.; Zhou, K. G.; Gou, X. C.; Xie, K. F.; Zhang, H. L.; Peng, Y. Effects of Dopant and Defect on the Adsorption of Carbon Monoxide on Graphitic Boron Nitride Sheet: A FirstPrinciples Study. Chem. Phys. Lett. 2010, 484, 266−270. (18) Jiao, Y.; Du, A.; Zhu, Z.; Rudolph, V.; Lu, G. Q. M.; Smith, S. C. A Density Functional Theory Study on CO2 Capture and Activation by Graphene-Like Boron Nitride with Boron Vacancy. Catal. Today 2011, 175, 271−275. (19) Lin, Q.; Zou, X. L.; Zhou, G.; Liu, R.; Wu, J.; Li, J.; Duan, W. H. Adsorption of NA/RNA Nucleobases on Hexagonal Boron Nitride Sheet: An Ab Initio Study. Phys. Chem. Chem. Phys. 2011, 13, 12225−12230. 23 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 24 of 46

(20) Ding, N.; Chen, X.; Wu, C. M. L.; Li, H. Adsorption of Nucleobase Pairs on Hexagonal Boron Nitride Sheet: Hydrogen Bonding Versus Stacking. Phys. Chem. Chem. Phys. 2013, 15, 10767−10776. (21) Shakourian-Fard, M.; Kamath, G.; Jamshidi, Z. Trends in Physisorption of Ionic Liquids on Boron-Nitride Sheets. J. Phys. Chem. C. 2014, 118, 26003-26016. (22) Singla, P.; Riyaz, M.; Singhal, S.; Goel, N. Theoretical Study of Adsorption of Amino Acids on Graphene and BN Sheet in Gas and Aqueous Phase with Empirical DFT Dispersion Correction. Phys. Chem. Chem. Phys. 2016, 18, 5597-5604. (23) Garcia, G.; Atilhan, M.; Aparicio, S. In Silico Rational Design of Ionic Liquids for the Exfoliation and Dispersion of Boron Nitride Nanosheets. Phys. Chem. Chem. Phys. 2016, 18, 1212-1224. (24) Ciofani, G.; Danti, S.; Genchi, G. G.; Mazzolai, B.; Mattoli, V. Boron Nitride Nanotubes: Biocompatibility and Potential Spill-Over in Nanomedicine. Small. 2013, 9, 1672–1685. (25) Lin, Y.; Williams, T.; Xu, T.-B.; Cao, W.; Elsayed-Ali, H.; Connell, J. Aqueous Dispersions of Few-Layered and Monolayered Hexagonal Boron Nitride Nanosheets from SonicationAssisted Hydrolysis: Critical Role of Water. J. Phys. Chem. C. 2011, 115, 2679–2685. (26) Sainsbury, T.; O’Neill, A.; Passarelli, M. K.; Seraffon, M.; Gohil, D.; Gnaniah, S.; Spencer, S. J.; Rae, A.; Coleman, J. N. Dibromocarbene Functionalization of Boron Nitride Nanosheets: Toward Band Gap Manipulation and Nanocomposite Applications. Chem. Mater. 2014, 26, 7039–7050. (27) Lei, W.; Mochalin, V. N.; Liu, D.; Qin, S.; Gogotsi, Y.; Chen, Y. Boron Nitride Colloidal Solutions, Ultralight Aerogels and Freestanding Membranes Through One-Step Exfoliation and Functionalization. Nat. Commun. 2015, 6, 8849. (28) Sainsbury, T.; Satti, A.; May, P.; Wang, Z.; McGovern, I.; Gun’ko, Y. K.; Coleman, J. Oxygen Radical Functionalization of Boron Nitride Nanosheets. J. Am. Chem. Soc. 2012, 134, 18758–18771. (29) Fu, X.; Hu, Y.; Zhang, T.; Chen, S. The Role of Ball Milled h-BN in the Enhanced Photocatalytic Activity: A Study Based on the Model of ZnO. Appl. Surf. Sci. 2013, 280, 828– 835.


Page 25 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(30) Wang, M.; Li, M.; Xu, L.; Wang, L.; Ju, Z.; Li, G.; Qian, Y. High Yield Synthesis of Novel Boron Nitride Submicro-boxes and their Photocatalytic Application under Visible Light Irradiation. Catal. Sci. Technol. 2011, 1, 1159–1165.

(31) Ide, Y.; Liu, F.; Zhang, J.; Kawamoto, N.; Komaguchi, K.; Bando, Y.; Golberg, D. Hybridization of Au Nanoparticle-loaded TiO2 with BN Nanosheets for Efficient Solar-Driven Photocatalysis. J. Mater. Chem. A. 2014, 2, 4150–4156. (32) Kumar, R.; Raut, D.; Ahmad, I.; Ramamurty, U.; Maji, T. K.; Rao, C. N. R. Functionality Preservation with Enhanced Mechanical Integrity in the Nanocomposites of the Metal–organic Framework, ZIF-8, with BN Nanosheets. Mater. Horiz. 2014, 1, 513–517. (33) Weng, Q.; Wang, X.; Wang, X.; Bando, Y.; Golberg, D. Functionalized Hexagonal Boron Nitride Nanomaterials: Emerging Properties and Applications. Chem. Soc. Rev. 2016, 45, 39894012. (34) Huang, C.; Ye, W.; Liu, Q.; Qiu, X. Dispersed Cu2O Octahedrons on h-BN Nanosheets for p-Nitrophenol Reduction. ACS Appl. Mater. Interfaces. 2014, 6, 14469−14476. (35) Hussain, T.; Searles, D. J.; Takahashi, K. Reversible Hydrogen Uptake by BN and BC3 Monolayers Functionalized with Small Fe Clusters: A Route to Effective Energy Storage. J. Phys. Chem. A. 2016, 120, 2009–2013. (36) Rosi, N. L.; Eckert, J; Eddaoudi, M; Vodak, DT; Kim, J; O'Keeffe, M; Yaghi, O. M. Hydrogen Storage in Microporous Metal-Organic Frameworks. Science. 2002, 300, 1127−1129. (37) Han, S. S.; Furukawa, H.; Yaghi, O. M.; Goddard III, W. A. Covalent Organic Frameworks as Exceptional Hydrogen Storage Materials. J. Am. Chem. Soc. 2008, 130, 11580−11581. (38) Chandrakumar, K. R. S.; Ghosh, S. K. Alkali-Metal-Induced Enhancement of Hydrogen Adsorption in C60 Fullerene: An ab Initio Study. Nano. Lett. 2008, 8, 13–19. (39) Chattaraj, P. K.; Bandaru, S.; Mondal, S. Hydrogen Storage in Clathrate Hydrates. J. Phys. Chem. A. 2011, 115, 187-193.



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 26 of 46

(40) Jhi, S.-H.; Kwon, Y.-K. Hydrogen Adsorption on Boron Nitride Nanotubes: A Path to Room-Temperature Hydrogen Storage. Phys. Rev. B: Condens. Matter Mater. Phys. 2004, 69, 245407. (41) Zhang, H.; Tong, C.-J.; Zhang, Y.; Zhang, Y.-N.; Liu, L.-M. Porous BN for Hydrogen Generation and Storage. J. Mater. Chem. A. 2015, 3, 9632–9637. (42) Collins, S. S. E.; Cittadini, M.; Pecharroman, C.; Martucci, A.; Mulvaney, P. Hydrogen Spillover between Single Gold Nanorods and Metal Oxide Supports: A Surface Plasmon Spectroscopy Study. ACS Nano. 2015, 9, 7846- 7856. (43) Abild-Pedersen, F.; Andersson, M. P. CO Adsorption Energies on Metals with Correction for High Coordination Adsorption Sites: A Density Functional Study. Surf. Sci. 2007, 601, 1747– 1753. (44) Brown, W. A.; King, D. A. NO Chemisorption and Reactions on Metal Surfaces: A New Perspective. J. Phys. Chem. B. 2000, 104, 2578-2595. (45) Chakraborty, D.; Chattaraj, P. K. Optical response and gas sequestration properties of metal cluster supported graphene nanoflakes. Phys. Chem. Chem. Phys. 2016, 18, 18811-18827. (46) Chu, S. N.; Sands, S.; Tomasik, M. R.; Lee, P. S.; Faye McNeill, V. Ozone Oxidation of Surface-Adsorbed Polycyclic Aromatic Hydrocarbons: Role of PAH−Surface Interaction. J. Am. Chem. Soc. 2010, 132, 15968–15975. (47) Lee, G.; Lee, B.; Kim, J.; Cho, K. Ozone Adsorption on Graphene: Ab Initio Study and Experimental Validation. J. Phys. Chem. C. 2009, 113, 14225–14229. (48) Hisatomi, T.; Kubota, J.; Domen, K. Recent Advances in Semiconductors for Photocatalytic and Photoelectrochemical Water Splitting. Chem. Soc. Rev. 2014, 43, 7520–7535. (49) Chen, X.; Shen, S.; Guo, L.; Mao, S. S. Semiconductor-based Photocatalytic Hydrogen Generation. Chem. Rev. 2010, 110, 6503–6570. (50) Leon, C. C.; Lee, J.; Ceyer, S. T. Oxygen Adsorption on Au–Ni(111) Surface Alloys. J. Phys. Chem. C. 2014, 118, 29043−29057. (51) Pinto, L. M. C.; Maia, G. Oxygen Adsorption on PdPt/Au(111) – DFT Calculations.


Page 27 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


J. Phys. Chem. C. 2015, 119, 8213−8216. (52) Lang, S. M.; Bernhardt, T. M.; Barnett, R. N.; Yoon, B.; Landman, U. Hydrogen-Promoted Oxygen Activation by Free Gold Cluster Cations. J. Am. Chem. Soc. 2009, 131, 8939–8951. (53) Sundberg, J.; Cameron, L. J.; Southon, P. D.; Kepert, C. J.; McKenzie, C. J. Oxygen Chemisorption/Desorption in a Reversible Single-Crystal-to-Single-Crystal Transformation. Chem. Sci. 2014, 5, 4017-4025. (54) Gerry, M. C. L.; Merer, A. J.; Sassenberg, U.; Steimle, T. C. The Microwave Spectrum of CuO, X 2Π, Measured with Optical Detection. J. Chem. Phys. 1987, 86, 4754-4761. (55) O’brien, L. C.; Wall, S. J.; Sieber, M. K. Fourier Transform Spectroscopy of the A2Σ+–X2Π Transition of AgO. J. Mol. Spectrosc. 1997, 183, 57-60. (56) O’Brien, L. C.; Hardimon, S. C.; O’Brien, J. J. Spectroscopy of AuO: Identification of the [10.7] Π 3/2 to X2 Π 3/2 Transition. J. Phys. Chem. A. 2004, 108, 11302-11306. (57) Dennington, R.; Keith, T.; Millam, J. GaussView, version 5; Semichem, Inc.: Shawnee Mission, KS, 2009. (58) Chai, J. D.; Head-Gordon, M. Long-range Corrected Hybrid Density Functionals with Damped Atom-Atom Dispersion Corrections. Phys. Chem. Chem. Phys., 2008, 10, 6615-6620. (59) Grimme, S.; Antony, J.; Ehrlich, S.; Krieg, H. A Consistent and Accurate ab initio Parametrization of Density Functional Dispersion Correction (DFT-D) for the 94 Elements H-Pu. J. Chem. Phys. 2010, 132, 154104-154119. (60) Chattaraj, P. K.; Sarkar, U.; Roy, D. R. Electrophilicity Index. Chem. Rev. 2006, 106, 20652091. (61) Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb, M. A.; Cheeseman, J. R.; Scalmani, G.; Barone, V.; Mennucci, B.; Petersson, G. A. et al. Gaussian 09, Revision C.01; Gaussian, Inc., Wallingford CT, 2010. (62) Bader, R. F. W. Atoms in Molecules: A Quantum Theory; Clarendon press: Oxford, UK, 1990. (63) Macchi, P.; Proserpio, D. M.; Sironi, A. Experimental Electron Density in a Transition Metal Dimer: Metal−Metal and Metal−Ligand Bonds. J. Am. Chem. Soc. 1998, 120, 13429–13435. 27 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 28 of 46

(64) Lu, T.; Chen, F. W. Multiwfn: A Multifunctional Wavefunction Analyzer. J. Comput. Chem. 2012, 33, 580-592. (65) te Velde, G.; Bickelhaupt, F. M.; Baerends, E. J.; van Gisbergen, S. J. A.; Fonseca Guerra, C.; Snijders, J. G.; Ziegler, T. Chemistry with ADF. J. Comput. Chem. 2001, 22, 931-967. (66) Parra, R. D.; Farrell, H. H. Binding Energy of Metal Oxide Nanoparticles. J. Phys. Chem. C. 2009, 113, 4786–4791.

Tables Table 1. Free energy change (∆G, kcal/mol) and reaction enthalpy change ( ∆H , kcal/mol) at 298K and 1 atmospheric pressure for the process: Guest + BNF → Guest@BNF; ZPE corrected dissociation energy (D0, kcal/mol)* for the dissociation process: Guest@BNF → BNF + Guest; HOMO-LUMO gap (Gap) (in eV), Polarizability (α) (in a.u.3); NBO charges on MO moieties (QK(MO)); distances in between the O/M centers of the MO moieties from the host surface (RMOBNF)

(in Ǻ); Wiberg bond index values for the O-B and M-N bonds of the Guest@BNF moieties

(WBIMO-BNF); most important stabilizing donor-acceptor interaction (E(2)) as given by second order perturbation theory analysis of Fock matrix in the NBO basis for the Guest@BNF moieties (in kcal/mol). (* D0 values have been computed according to the following expression:

D0 = {( E1 + E 2 ) − E3 } where E1, E2 and E3 correspond to ZPE corrected energies of optimized geometries of the MO/(CuO)2, BNF and MO/(CuO)2@BNF moieties. In order to evaluate ∆G/ ∆H , we have used the expression: ∆X = { X 1 − ( X 2 + X 3 )} where X1, X2 and X3 correspond to Free energy/enthalpy of MO/(CuO)2@BNF, MO/(CuO)2 and BNF moieties. Similar expressions have been used in all other cases all throughout the manuscript to evaluate D0/∆G/ ∆H ). Systems

∆G

∆H

D0

Gap

α

QK(MO)

RMO-

WBIMO-

BNF

BNF

E(2)

CuO@BNF

-33.66

-45.75

45.52

7.3

440.6

Cu=0.82, O=-0.58

OB=1.56, CuN=2.09

OB=0.62, CuN=0.13

LPN to LP*O =29.10

AgO@BNF

-7.32

-19.24

19.08

6.9

443.6

Ag=0.84, O=-0.59

OB=1.54, Ag-

OB=0.64, Ag-N=

BD*B–N to LP*Ag


Page 29 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


N=2.47

0.07

=14.61

AuO@BNF

3.98

-7.35

7.31

6.2

462.6

Au=0.64, O=-0.60

OB=1.61, AuN=3.17

O-B =0.52, AuN=0.01

LPN to BD*B-O =10.81

(CuO)2@BNF

-7.52

-21.36

21.31

5.8

475.2

Cu=0.95,0.89 O=-0.85,0.83

OB=1.59, CuN=2.02

OB=0.53, Cu-N= 0.20

BDO-Cu to LPB =300.11

Table 2. Electron density descriptors (in a.u.) at the bond critical points (BCP) for the Guest@BNF moieties. Systems

BCP

ρ(rc)

∇2ρ(rc)

H(rc)

-G(rc)/V(rc)

ELF

CuO@BNF

O-BMO-BN

0.12

0.42

-0.08

0.69

0.18

Cu-NMO-BN

0.07

0.33

0.01

0.95

0.12

O-BMO-BN

0.13

0.47

-0.09

0.70

0.18

Ag-NMO-BN

0.04

0.15

0.00

0.94

0.11

O-BMO-BN

0.11

0.33

-0.07

0.69

0.17

Au-NMO-BN

0.01

0.04

0.00

1.12

0.06

O-BMO-BN

0.11

0.37

-0.07

0.70

0.17

Cu-NMO-BN

0.08

0.37

0.00

0.92

0.15

AgO@BNF

AuO@BNF

(CuO)2@BNF

Table 3. EDA results of guest@BNF studied at the revPBE-D3/TZ2P// wb97xd/6311G(d,p)/SDD level (kcal/mol). Systems

Fragments

∆Eel

∆EPauli

∆Eorb

∆Edisp

∆Etot

CuO@BNF

[CuO]+[BNF]

-167.85

303.98

-186.44

-11.84

-62.15

AgO@BNF

[AgO]+[BNF]

-131.35

258.92

-169.61

-14.60

-56.64

AuO@BNF

[AuO]+[BNF]

-85.38

191.17

-124.39

-15.40

-34.00

(CuO)2@BNF

[(CuO)2]+[BNF]

-164.31

266.99

-140.44

-17.77

-55.52



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 30 of 46

Table 4. Free energy change (∆G, kcal/mol) and reaction enthalpy change ( ∆H , kcal/mol) at 298K

and

1

atmospheric

pressure

for

the

process:

CO/NO/O2/H2O/H2/O3

+

MO/(CuO)2@BNF/BNF → CO/NO/O2/H2O/H2/O3@MOBNF/BNF/(CuO)2BNF; ZPE corrected dissociation

energy

(D0,

kcal/mol)

for

the

dissociation

process:

CO/NO/O2/H2O/H2/O3@MOBNF/BNF/(CuO)2BNF→CO/NO/O2/H2O/H2/O3+MO/(CuO)2@BNF /BNF; HOMO-LUMO gap (Gap) (in eV); Polarizability (α) (in a.u.3) for the concerned systems. Systems

∆G

∆H

D0

Gap

α

CO@BNF

4.14

-2.30

2.79

10.1

425.4

NO@BNF

3.88

-2.96

3.41

8.1

423.5

O2@BNF

5.26

-2.97

2.90

8.9

422.0

H2O@BNF

1.60

-6.19

6.19

10.2

421.6

H2@BNF

5.29

-0.15

-0.15

10.1

419.4

O3@BNF

4.25

-4.99

5.53

5.8

427.8

CO@CuOBNF

0.58

-7.91

7.99

7.4

457.2

NO@CuOBNF

12.79

1.17

1.86

5.58

463.4

O2@CuOBNF

-0.69

-9.52

9.56

6.2

461.7

H2O@CuOBNF

-22.19

-32.99

31.98

7.6

451.2

H2@CuOBNF

-4.40

-11.88

10.69

7.9

446.3

O3@CuOBNF

-16.17

-27.74

27.58

4.9

474.9

CO@AgOBNF

2.33

-5.05

5.45

7.1

453.4

NO@AgOBNF

17.89

7.13

7.49

6.4

461.5

O2@AgOBNF

1.57

-6.03

6.35

5.7

455.1

H2O@AgOBNF

-17.44

-27.84

26.96

7.5

452.7

H2@AgOBNF

-1.16

-8.00

7.06

7.7

451.2

O3@AgOBNF

-8.31

-20.05

19.98

5.9

492.1

CO@AuOBNF

-37.71

-48.96

48.20

6.9

474.3

NO@AuOBNF

-3.39

-13.02

12.71

6.7

469.4

O2@AuOBNF

-2.51

-11.70

11.68

5.7

472.7


Page 31 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


H2O@AuOBNF

-24.82

-37.29

35.99

7.4

461.4

H2@AuOBNF

-16.27

-24.77

23.27

7.4

462.9

O3@AuOBNF

-16.16

-29.25

28.96

4.2

520.9

CO@(CuO)2BNF

-16.17

-25.82

25.52

5.8

488.4

NO@(CuO)2BNF

-17.81

-26.74

26.69

6.0

486.5

O2@(CuO)2BNF

3.53

-4.79

4.94

5.6

486.6

H2O@(CuO)2BNF

-17.26

-27.38

26.60

6.0

478.1

H2@(CuO)2BNF

-0.27

-7.57

6.54

5.9

479.6

O3@(CuO)2BNF

-7.74

-18.36

18.65

4.7

516.8

Table 5. NBO charges on MO moieties (QK(MO)); NBO charges on CO/NO/O2/H2O/H2/O3 moieties (QK(Ad)); distances in between the O/M centers of the MO moieties from the host surface (RMO-BNF) (in Ǻ); distance in between the adsorbates and adsorbent (RAd-MO@BNF/BNF) (in Ǻ); Wiberg bond index values for the different bonds of the adsorbates at the adsorbed state (WBIAd); most important stabilizing donor-acceptor interaction (E(2)) as given by second order perturbation theory analysis of Fock matrix in the NBO basis for the Guest@BNF/MOBNF moieties (in kcal/mol). Systems

QK(MO)

QK(Ad)

RMO-BNF

RAd-MO@BNF/BNF

WBIAd

E(2)

CO@BNF

-

C=0.48 O=-0.47

-

C-B= 3.25

C-O=2.27

N=0.19 O=-0.18

-

N-N= 3.15

N-O=2.09

-

O=0.01 O=0.01

-

O-B= 3.22

O-O =1.51

H2O@BNF

-

H=0.46 H=0.46 O=-0.89

-

H-N= 2.53

O-H=0.79, 0.79

H2@BNF

-

H=0.00 H=0.01

-

H-N= 2.89

H-H=0.99

O3@BNF

-

O=0.31 O=-0.14 O=-0.15

-

O-B= 3.02

O-O=1.43 O-O= 1.42

LPC to BD*N-B =2.77 LPN to LP*B =2.29 LPO to LP*B =1.40 BDO-H to BD*B-N =1.65 BDB-N to BD*H-H =0.35 LPO to BD*B-N =2.39

NO@BNF

-

O2@BNF

Cu=0.75 O=-0.62

C=0.63 O=-0.57

Cu-O= 2.01

C-O= 2.08

CO@CuOBNF

Cu-N= 2.57 O-B= 1.55

LPO to LP*Cu



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

NO@CuOBNF

Cu=0.86 O=-0.76

O=-0.17 N=0.22

Cu-N= 1.94 O-B= 1.51

Cu-N= 1.85

Page 32 of 46

= 14.95 BD*N-O to BD*Cu-

N-O= 1.99

O

O2@CuOBNF

Cu=0.79 O=-0.59

O=-0.11 O=0.08

Cu-N= 2.27 O-B= 1.54

Cu-O= 1.96

O-O =1.43

H2O@CuOBNF

Cu=0.74 O=-0.60

O=-0.94 H=0.50 H=0.53

Cu-N= 2.79 O-B= 1.55

Cu-O= 1.95

O-H= 0.67, 0.74

H2@CuOBNF

Cu=0.67 O=-0.57

H= 0.03, 0.04

Cu-N= 2.25 O-B= 1.54

Cu-H= 1.65

H-H= 0.80

O3@CuOBNF

Cu=0.79 O=-0.54

O=-0.21, -0.24, 0.27

Cu-N= 2.10 O-B= 1.54

Cu-O= 1.98

O-O= 1.28, 1.24

=254.25 LPO to LP*Cu =16.72 LPO to LP*Cu = 25.63 BDH -H to LP*Cu = 25.61 BDCu-O to BDOO

CO@AgOBNF

Ag=0.81 O=-0.58

C=0.57 O=-0.52

Ag-N= 2.50 O-B= 1.53

Ag-O= 2.63

C-O=2.18

NO@AgOBNF

Ag=0.79 O=-0.83

N=0.32 O= 0.09

Ag-N= 2.62 O-B= 1.53

O-O= 1.85

N-O= 2.31

O2@AgOBNF

Ag=0.78 O=-0.59

O=-0.06 O=0.10

Ag-N= 2.62 O-B= 1.54

Ag-O= 2.40

O-O=1.49

H2O@AgOBNF

Ag=0.74 O=-0.58

O=-0.94 H=0.49 H=0.52

Ag-N= 2.91 O-B= 1.53

Ag-O= 2.23

O-H=0.69, 0.75

H2@AgOBNF

Ag=0.73 O=-0.58

H=0.02, 0.03

Ag-N= 2.66 O-B= 1.54

Ag-H= 1.90

H-H=0.88

O3@AgOBNF

Ag=0.99 O=-0.55

O=-0.38, 0.20, 0.31

Ag-N= 2.35 O-B= 1.54

Ag-O= 2.14

O-O=1.15, 1.07

CO@AuOBNF

Au=0.50 O=-0.66

C=0.53 O=-0.36

Au-N= 3.21 O-B= 1.56

Au-C= 1.90

C-O=2.27

NO@AuOBNF

Au=0.21 O=-0.57

N=-0.02 O=-0.25

Au-N= 3.34 O-B= 1.50

Au-N= 2.04

N-O= 1.98

= 511.57 LP O to LP*Ag =4.35 LPO to BD*N-O =161.96 LPO to LP*Ag =7.11 LP O to LP*Ag =13.94 BDH-H to LP*Ag =14.03 LPO to LP*Ag =22.29 LPC to BD*OAu= 110.33 LPO to BD*Au N

O2@AuOBNF

Au=0.61 O=-0.59

O=-0.08 O=0.13

Au-N= 3.15 O-B= 1.59

Au-O= 2.21

= 45.74 LPO to BD*O-

O-O=1.47

Au

H2O@AuOBNF

Au=0.58 O=-0.53

O=-0.90 H=0.50 H=0.53

Au-N= 3.03 O-B= 1.61

Au-O= 2.16

O-H= 0.67, 0.74


=21.12 LPO to BD*O= Au

Page 33 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


H2@AuOBNF

Au=0.55 O=-0.63

H=0.05, 0.07

Au-N= 3.24 O-B= 1.58

Au-H= 1.70

28.68 LP*H to BD*O-

H-H=0.69

Au

O3@AuOBNF

Au=0.62 O=-0.60

O= -0.24, 0.28, 0.04

Au-N= 3.24 O-B= 1.58

Au-O= 2.08

O-O= 1.17, 1.39

CO@(CuO)2BNF

Cu=0.57, 0.99, O=-0.78, -0.77

C=0.52, O=-0.38

O-B= 1.55, Cu-N= 2.02

Cu-C= 1.82

C-O= 2.28

NO@(CuO)2BNF

Cu=0.83, 1.01, O=-0.93,-0.83

N=0.17, O=0.04

O-B= 1.55, Cu-N= 2.01

Cu-N= 1.89

N-O=2.11

O2@(CuO)2BNF

Cu=1.01, 1.04 O=-0.74, -0.90

O= -0.18, -0.03

O-B= 1.53, Cu-N= 2.04

Cu-O= 2.00

O-O= 1.37

H2O@(CuO)2BNF

Cu=0.88, 0.87, O=-0.85, -0.85

H=0.53, 0.50, O=-0.89

O-B= 1.58, Cu-N= 2.02

Cu-O= 1.98

O-H= 0.64, 0.62

H2@(CuO)2BNF

Cu= 0.73, 0.94, O=-0.82, -0.78

H=0.03, 0.06

O-B= 1.59, Cu-N= 2.02

Cu-H= 1.71

H-H= 0.82

O3@(CuO)2BNF

Cu= 0.86, 0.96, O= -0.81, -0.79

O= 0.32, -0.09, 0.27

O-B= 1.57, Cu-N= 2.03

Cu-O= 1.94

O-O= 1.45, 1.25

Table 6. Electron density descriptors (in a.u.) at the bond critical points (BCP) for the CO/NO/O2/H2O/H2/O3@MO@BNF/BNF moieties. Herein, subscripts MOL-SURF, MO-BN, MOL refer to the BCPs belonging to the adsorbate-BNF/MO@BNF, MO-BNF and adsorbate moieties respectively. Systems

BCP

ρ(rc)

∇2ρ(rc)

H(rc)

-G(rc)/V(rc)

ELF

CO@BNF

C-NMOL-SURF

0.01

0.02

0.00

1.36

0.02

C-OMOL

0.49

0.75

-0.86

0.55

0.41

N-NMOL-SURF

0.01

0.03

0.00

1.26

0.03

N-OMOL

0.59

-2.01

-1.11

0.35

0.79

O-NMOL-SURF

0.01

0.02

0.00

1.21

0.01

NO@BNF

O2@BNF


=44.11 LPO to BD* O= Au 29.71 LP*Cu to BD*Cu C= 77.83 BD*Cu – N to BD*CuO= 90.95 BD*O O to BD*Cu = O 25.95 LPO to LP*Cu = 30.04 BDH-H to LP*Cu = 37.83 BDCu - O to LPO = 32.10


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

H2O@BNF

H2@BNF

O3@BNF

CO@CuOBNF

Page 34 of 46

O-OMOL

0.55

-0.85

-0.70

0.41

0.83

H-NMOL-SURF

0.01

0.03

0.00

1.19

0.04

O-HMOL

0.37

-2.54

-0.71

0.09

0.98

O-HMOL

0.37

-2.55

-0.71

0.09

0.98

H-NMOL-SURF

0.01

0.02

0.00

1.27

0.02

H-HMOL

0.26

-1.05

-0.26

0.00

0.99

O-NMOL-SURF

0.01

0.03

0.00

1.16

0.02

O-OMOL

0.49

-0.48

-0.56

0.44

0.79

O-OMOL

0.49

-0.47

-0.56

0.44

0.79

O-BMO-BN

0.12

0.45

-0.08

0.70

0.17

Cu-NMO-BN

0.03

0.08

0.00

0.88

0.09

O-CuMOL-

0.06

0.46

0.01

1.08

0.06

0.47

0.75

-0.80

0.55

0.39

Cu-NMO-BN

0.09

0.40

-0.01

0.86

0.20

O-BMO-BN

0.15

0.49

-0.11

0.68

0.21

Cu-NMOL-

0.12

0.48

-0.03

0.82

0.24

0.56

-1.81

-0.97

0.35

0.82

O-BMO-BN

0.13

0.46

-0.08

0.70

0.18

Cu-NMO-BN

0.05

0.19

0.00

0.97

0.11

O-CuMOL-

0.07

0.50

0.00

1.03

0.09

0.53

-0.75

-0.65

0.41

0.83

O-BMO-BN

0.12

0.44

-0.08

0.71

0.17

Cu-NMO-BN

0.02

0.05

0.00

0.86

0.08

O-CuMOL-

0.08

0.55

0.00

1.01

0.08

0.34

2.39

-0.66

0.09

0.98

0.37

-2.60

-0.72

0.09

0.98

0.13

0.47

-0.09

0.70

0.18

SURF

C-OMOL NO@CuOBNF

SURF

O-NMOL O2@CuOBNF

SURF

O-OMOL H2O@CuOBNF

SURF

O-HMOL O-HMOL H2@CuOBNF

O-BMO-BN


Page 35 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Cu-NMO-BN

0.05

0.21

0.00

0.98

0.11

H-CuMOL-

0.09

0.44

-0.01

0.90

0.15

0.23

-0.79

-0.21

0.06

0.99

O-BMO-BN

0.13

0.46

-0.08

0.70

0.18

Cu-NMO-BN

0.07

0.30

0.00

0.95

0.13

O-CuMOL-

0.05

0.24

0.00

1.03

0.08

SURF

0.08

0.53

0.00

1.02

0.08

O-OMOL

0.44

-0.35

-0.45

0.45

0.79

O-OMOL

0.45

-0.39

-0.49

0.44

0.79

O-BMO-BN

0.13

0.48

-0.09

0.70

0.18

Ag-NMO-BN

0.04

0.14

0.00

0.94

0.11

O-AgMOL-

0.02

0.09

0.00

1.05

0.04

0.48

0.71

-0.83

0.55

0.41

Ag-NMO-BN

0.04

0.16

0.00

0.94

0.11

O-BMO-BN

0.13

0.44

-0.09

0.69

0.19

O-OMOL-SURF

0.09

0.36

0.00

0.96

0.27

N-OMOL

0.64

-1.96

-1.37

0.39

0.71

O-BMO-BN

0.13

0.48

-0.09

0.70

0.18

Ag-NMO-BN

0.03

0.11

0.00

0.96

0.09

O-AgMOL-

0.04

0.18

0.00

1.02

0.07

0.55

-0.84

-0.69

0.41

0.83

O-BMO-BN

0.13

0.47

-0.09

0.70

0.18

Ag-NMO-BN

0.02

0.06

0.00

1.02

0.06

O-AgMOL-

0.06

0.30

0.00

0.98

0.09

0.34

-2.42

-0.67

0.09

0.98

0.37

-2.59

-0.72

0.09

0.98

SURF

H-HMOL

O3@CuOBNF

SURF

O-CuMOL-

CO@AgOBNF

SURF

C-OMOL NO@AgOBNF

O2@AgOBNF

SURF

O-OMOL H2O@AgOBNF

SURF

O-HMOL



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 36 of 46

O-HMOL H2@AgOBNF

O-BMO-BN

0.13

0.48

-0.09

0.71

0.18

Ag-NMO-BN

0.03

0.09

0.00

0.98

0.09

H-AgMOL-

0.07

0.27

-0.01

0.88

0.16

0.24

-0.88

-0.23

0.03

0.99

O-BMO-BN

0.13

0.46

-0.08

0.70

0.17

Ag-NMO-BN

0.05

0.18

-0.01

0.89

0.16

O-AgMOL-

0.08

0.37

-0.01

0.93

0.15

0.40

-0.25

-0.39

0.46

0.79

0.37

-0.14

-0.33

0.47

0.78

O-BMO-BN

0.12

0.42

-0.08

0.71

0.17

Au-NMO-BN

0.01

0.04

0.00

1.14

0.05

C-AuMOL-

0.16

0.46

-0.08

0.70

0.34

0.49

0.79

-0.08

0.55

0.39

O-BMO-BN

0.14

0.59

-0.09

0.73

0.16

Au-NMO-BN

0.01

0.03

0.00

1.05

0.06

N-AuMOL-

0.13

0.30

-0.05

0.72

0.37

0.55

-1.67

-0.88

0.34

0.84

O-BMO-BN

0.11

0.37

-0.07

0.69

0.17

Au-NMO-BN

0.01

0.05

0.00

1.12

0.06

O-AuMOL-

0.06

0.34

0.00

0.97

0.09

0.55

-0.83

-0.68

0.41

0.83

O-BMO-BN

0.10

0.34

-0.07

0.69

0.17

Au-NMO-BN

0.02

0.06

0.00

1.08

0.07

O-AuMOL-

0.08

0.38

-0.01

0.93

0.12

0.33

-2.38

-0.66

0.09

0.98

SURF

H-HMOL O3@AgOBNF

SURF

O-OMOL O-OMOL CO@AuOBNF

SURF

C-OMOL NO@AuOBNF

SURF

N-OMOL O2@AuOBNF

SURF

O-OMOL H2O@AuOBNF

SURF

O-HMOL


Page 37 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


H2@AuOBNF

O-HMOL

0.37

-2.60

-0.72

0.09

0.98

O-BMO-BN

0.11

0.39

-0.07

0.70

0.16

Au-NMO-BN

0.01

0.04

0.00

1.15

0.05

H-AuMOL-

0.12

0.36

-0.05

0.73

0.28

0.20

-0.62

-0.02

0.12

0.99

O-BMO-BN

0.11

0.40

-0.07

0.71

0.16

Au-NMO-BN

0.01

0.04

0.00

1.09

0.05

O-AuMOL-

0.09

0.50

-0.01

0.92

0.13

0.42

-0.25

-0.42

0.46

0.79

0.51

-0.60

-0.61

0.43

0.81

O-BMO-BN

0.13

0.44

-0.08

0.70

0.18

Cu-NMO-BN

0.08

0.36

-0.01

0.91

0.15

C-CuMOL-

0.12

0.57

-0.04

0.82

0.20

0.49

0.80

-0.86

0.55

0.40

O-BMO-BN

0.13

0.44

-0.08

0.70

0.18

Cu-NMO-BN

0.08

0.37

-0.01

0.91

0.16

N-CuMOL-

0.10

0.54

-0.02

0.90

0.15

0.61

-2.06

-1.13

0.35

0.80

O-BMO-BN

0.14

0.48

-0.09

0.69

0.19

Cu-NMO-BN

0.08

0.34

-0.01

0.92

0.15

O-CuMOL-

0.07

0.38

0.00

1.03

0.14

0.54

-0.82

-0.67

0.41

0.83

O-BMO-BN

0.11

0.40

-0.07

0.70

0.17

Cu-NMO-BN

0.08

0.37

-0.01

0.92

0.15

O-CuMOL-

0.07

0.48

0.00

1.02

0.08

0.35

-2.50

-0.69

0.08

0.98

SURF

H-HMOL O3@AuOBNF

SURF

O-OMOL O-OMOL CO@(CuO)2BNF

SURF

C-OMOL NO@(CuO)2BNF

SURF

N-OMOL O2@(CuO)2BNF

SURF

O-OMOL H2O@(CuO)2BNF

SURF

O-HMOL



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

H2@(CuO)2BNF

Page 38 of 46

O-HMOL

0.37

-2.60

-0.72

0.09

0.98

O-BMO-BN

0.11

0.39

-0.07

0.70

0.17

Cu-NMO-BN

0.08

0.37

-0.01

0.91

0.15

H-CuMOL-

0.08

0.38

-0.01

0.94

0.13

0.24

-0.87

-0.23

0.04

0.99

O-BMO-BN

0.12

0.41

-0.08

0.70

0.17

Cu-NMO-BN

0.08

0.36

-0.01

0.91

0.15

O-CuMOL-

0.08

0.57

0.00

1.01

0.08

0.44

-0.31

-0.45

0.45

0.79

0.51

-0.56

-0.60

0.43

0.80

SURF

H-HMOL

O3@(CuO)2BNF

SURF

O-OMOL O-OMOL

Table 7. EDA results of CO/NO/O2/H2O/H2/O3@MO@BNF/BNF studied at the revPBED3/TZ2P// wb97xd/6-311G(d,p)/SDD level (kcal/mol). Systems

Fragments

∆Eel

∆EPauli

∆Eorb

∆Edisp

∆Etot

CO@BNF

[CO]+[BNF]

-1.11

3.89

-1.44

-4.78

-3.45

H2O@BNF

[H2O]+[BNF]

-3.14

8.00

-3.07

-5.83

-4.03

H2@BNF

[H2]+[BNF]

-0.77

2.55

-0.62

-2.58

-1.42

O3@BNF

[O3]+[BNF]

-2.79

8.40

-3.64

-6.81

-4.84

NO@BNF

[NO]+[BNF]

-1.89

7.24

-2.45

-4.75

-1.85

O2@BNF

[O2]+[BNF]

-1.32

4.44

-2.39

-4.05

-3.32

CO@CuOBNF

[CO]+[CuO@BNF]

-23.35

37.32

-27.87

-4.74

-18.64

H2O@CuOBNF

[H2O]+[CuO@BNF]

-61.93

73.74

-43.42

-5.12

-36.73

H2@CuOBNF

[H2]+[CuO@BNF]

-46.49

64.80

-42.61

-1.55

-25.86

O3@CuOBNF

[O3]+[CuO@BNF]

-59.30

87.95

-68.85

-2.53

-42.74

O2@CuOBNF

[O2]+[CuO@BNF]

-29.98

45.91

-31.20

-2.17

-17.44

NO@CuOBNF

[NO]+[CuO@BNF]

-54.73

137.63

-123.26

-2.05

-42.41


Page 39 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


CO@AgOBNF

[CO]+[AgO@BNF]

-6.88

13.79

-13.74

-5.79

-12.63

H2O@AgOBNF

[H2O]+[AgO@BNF]

-44.75

50.87

-31.08

-5.24

-30.21

H2@AgOBNF

[H2]+[AgO@BNF]

-34.21

45.90

-28.44

-1.02

-17.77

O3@AgOBNF

[O3]+[AgO@BNF]

-64.76

101.11

-73.79

-2.82

-40.26

O2@AgOBNF

[O2]+[AgO@BNF]

-10.58

21.60

-22.52

-3.95

-15.45

NO@AgOBNF

[NO]+[AgO@BNF]

-41.42

110.04

-106.04

-6.48

-43.89

CO@AuOBNF

[CO]+[AuO@BNF]

-148.21

186.64

-94.71

-2.56

-58.85

H2O@AuOBNF

[H2O]+[AuO@BNF]

-59.78

62.89

-38.95

-6.35

-42.18

H2@AuOBNF

[H2]+[AuO@BNF]

-90.08

118.81

-62.78

-0.73

-34.79

O3@AuOBNF

[O3]+[AuO@BNF]

-59.03

88.22

-66.14

-7.12

-44.08

O2@AuOBNF

[O2]+[AuO@BNF]

-21.98

44.05

-36.96

-3.28

-18.17

NO@AuOBNF

[NO]+[AuO@BNF]

-88.54

223.60

-182.45

-1.77

-49.16

H2@(CuO)2BNF

[H2]+[(CuO)2BNF]

-38.30

57.66

-30.27

-1.01

-11.92

H2O@(CuO)2BNF

[H2O]+[(CuO)2BNF]

-63.20

73.48

-30.44

-3.05

-23.20

CO@(CuO)2BNF

[CO]+[(CuO)2BNF]

-93.54

117.64

-61.75

-3.46

-41.12

O3@(CuO)2BNF

[O3]+[(CuO)2BNF]

-46.38

69.78

-47.38

-5.58

-29.56

O2@(CuO)2BNF

[O2]+[(CuO)2BNF]

-28.32

55.71

-42.61

-3.41

-18.64

NO@(CuO)2BNF

[NO]+[(CuO)2BNF]

-51.62

99.82

-86.99

-1.82

-40.61

Figures



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 40 of 46

Figure 1: Minimum energy structures of BNF, Electron localization function at the XY plane for BNF, minimum energy structures of AuO@BNF, AgO@BNF and CuO@BNF respectively (in clockwise direction).


Page 41 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Figure 2: Minimum energy structures of CO@BNF, H2O@BNF, NO@BNF, O3@BNF, O2@BNF and H2@BNF respectively (in clockwise direction).



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 42 of 46

Figure 3: Minimum energy structures of CO@CuOBNF, H2O@CuOBNF, H2@CuOBNF, O3@CuOBNF, O2@CuOBNF and NO@CuOBNF respectively (in clockwise direction).


Page 43 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Figure 4: Minimum energy structures of CO@AgOBNF, H2O@AgOBNF, H2@AgOBNF, O3@AgOBNF, O2@AgOBNF and NO@AgOBNF respectively (in clockwise direction).



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 44 of 46

Figure 5: Minimum energy structures of CO@AuOBNF, H2O@AuOBNF, H2@AuOBNF, O3@AuOBNF, O2@AuOBNF and NO@AuOBNF respectively (in clockwise direction).


Page 45 of 46

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Figure 6: Minimum energy structures of (CuO)2, (CuO)2@BNF, CO@(CuO)2BNF, H2O@(CuO)2BNF, O3@(CuO)2BNF, O2@(CuO)2BNF, NO@(CuO)2BNF and H2@(CuO)2BNF respectively (in clockwise direction).


The Journal of Physical Chemistry Page 46 of 46

1 2 3 4 5 6 7

ACS Paragon Plus Environment

Sequestration and Activation of Small Gas Molecules on BN-Flakes

Recommend Documents