Boron and Nitrogen Co-Doping of Graphynes without Inducing Empty

Subscriber access provided by University of Winnipeg Library

C: Surfaces, Interfaces, Porous Materials, and Catalysis

Boron and Nitrogen Co-Doping of Graphynes without Inducing Empty or Doubly Filled States in #-Conjugated Systems Huan Liu, Xingfa Gao, and Yuliang Zhao J. Phys. Chem. C, Just Accepted Manuscript • DOI: 10.1021/acs.jpcc.8b10684 • Publication Date (Web): 12 Dec 2018 Downloaded from http://pubs.acs.org on December 13, 2018

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 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 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.

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 18 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

Boron and Nitrogen Co-doping of Graphynes without Inducing Empty or Doubly Filled States in π-Conjugated Systems Huan Liu,† Xingfa Gao,*,† and Yuliang Zhao‡ †College

of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang

330022, China ‡CAS

Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center

for Excellence in Nanoscience, National Center for Nanoscience and Technology of China, Beijing 100190, China

ABSTRACT: Substitutional B and N doping is a powerful way to modulate the electronic properties of carbon π-conjugated materials. However, the B and N dopants in all the previously reported hybrid materials have either doubly-filled or empty pz orbitals, causing large reductions of carrier mobilities for the materials. Using density functional theory calculations, we demonstrate a different BN co-doping method for graphynes, which does not introduce any empty or doubly filled pz states into the π-systems. Instead, electron donations between carbon and dopant atoms occur only in the σ-bond frameworks, and π-electron configurations of the hybrid graphynes are absolutely the same as those of the pristine graphynes. It thus allows opening large bandgaps for

ACS Paragon Plus Environment

1

The Journal of Physical Chemistry 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 18

graphynes and simultaneously best reserving their prominent carrier mobilities. Following this doping method, the BCN atoms form subunits that resemble base-stabilized borylenes, which are already experimentally synthesizable. Therefore, the results pave a way to the bottom-up design and synthesis of hybrid graphyne-like materials for use as high-performance, post-silicon electronics.

1. INTRODUCTION Substitutional heteroatom doping is a powerful way to modulate the electronic properties of materials.1 For π-conjugated carbon materials like graphene,2 carbon nanotubes,3 and graphynes,4,5 boron (B) and nitrogen (N) atoms are the best size-compatible substitutes of carbon (C) owing to their close atomic radii. Therefore, numerous efforts have been made to dope B, N, or them both into carbon π-networks, aiming to obtain hybrid materials with sizable bandgaps and carrier mobilities,6-8 which are prerequisites for use as high performance, post-silicon electronics.9 However, in all these hybrid materials reported so far, the B and N dopants have either doubly-filled (Figure 1a) or empty (Figure 1b) pz orbitals, which generate charged acceptor or donor states in the π-conjugated systems as electron scattering centers.10-14 Besides, when the dopant concentration rises over 5%, the dopant states become strongly localized, further decreasing the electron conductivities.15 Resultantly, the currently reported substitutional doping strategies are hard to achieve hybrid π-materials with semiconductor performances superior to silicon.16


2

Page 3 of 18 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


a)

b)

pz

pz

N

B

Lewis base pz pz

c) N

C

B

borylene pz sp2

N

C

NCB

sp2

B

sp2

Figure 1. B and N doped π-conjugated carbon networks. The N’s pz (a) and B’s pz (b) orbitals are doubly filled and empty, respectively. In contrast, all pz orbitals of atoms in (c) are singly occupied. The electronic configuration of the NCB unit is identical to that of base-stabilized borylene. Solid arrows indicate electron donations. Using density functional theory (DFT) calculations, we hereby demonstrate a different BN co-doping method for graphynes, π-materials consisting of sp and sp2 carbons.4 This doping is realized by substituting graphyne C≡C−C structural units with the N≡C−B (NCB) units, which does not introduce any empty or doubly filled pz states into the π-conjugated systems and electron donations occur only in the σ-bond frameworks (Figure 1c). It thus allows opening large bandgaps for graphynes and simultaneously best reserving their prominent carrier mobilities. Encouragingly, the NCB unit can be regarded as the experimentally synthesizable base-stabilized borylene species, in which the isocyanide subunit (−N≡C:) serves as the Lewis base donating its σ-electron lone pair to the empty sp2 orbital of B atom (Figure 1c).17-19 Therefore, the results reported here pave a way to the bottom-up synthesis of hybrid graphyne-like materials for use as high-performance, post-silicon semiconductors. 2. COMPUTATIONAL DETAILS


3


Page 4 of 18

DFT calculations were performed by Vienna ab initio Simulation Package (VASP).20-22 The generalized gradient approximation (GGA) and Perdew-Burkee-Ernzerhof (PBE)23 of projector augmented wave (PAW) method24 were used. All geometry optimizations and energy calculations were performed in a planewave basis set with an energy cut-off of 500 eV and Gaussian smearing of 0.05 eV. Vacuum heights of 15 Å were set to the vertical directions to avoid the interaction between periodic images. The Brillouin zones were sampled with a (7 × 7 × 1) Monkhorst-Pack25 mesh for the k-point sampling. All the atoms were fully relaxed and conjugated gradient algorithm was used upon geometry optimization. In all calculations, the convergence criteria of electronic energy and force were set to 105 eV and 0.01 eV Å−1, respectively. For the AIMD simulation, a supercell consisting of 48 atoms (8 B, 8 N, and 32 C) was used in conjugation with the Gamma point approximation. The electron mobility for 2a and 2b were calculated with the following equation26,27 𝜇=

𝑒ℏ3𝐶 𝑘B𝑇𝑚e ∗ 𝑚d(𝐸1)2

where 𝑚e is the effective mass in the transport direction and md the average effective mass determined by 𝑚d = 𝑚x∗ 𝑚y∗ , mx* and my* are electron effective masses for directions x and y, respectively, e is the charge of an electron, T is temperature, ℏ and kB are the Planck and Boltzmann constants, respectively. The term E1 represents the deformation potential constant of the conduction-band maximum along the transport direction, defined by E1 = ΔE / (Δl / l0), where ΔE is the band energy (relative to the vacuum level) shift. l0 is the lattice constant in the transport direction and Δl is the deformation of l0.28-30 To obtain the deformation potential constant C, we dilate the lattice cell up to 1.5% along the transport direction. We can obtain the C by quadratic fitting of the total energy E with respect to the dilation (E – E0) / S0 = (C/2) (Δl / l0)2, where E is the total energy and S0 is the lattice volume at equilibrium for a 2D system. The


4

Page 5 of 18 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


temperature used for the mobility calculations is 298 K. Figure S7 illustrates some details for the calculations of deformation potential constant and 2D elastic constants. The El and C for 2a are 154.21 N m−1 and 2.44 eV, respectively, and those for 2b are 167.82 N m−1 and 2.65 eV, respectively. 3. RESULTS AND DISCUSSION We first studied the possibility of implementing the NCB structural unit into π-conjugated molecules, with molecule 1 as the example (Figure 2). 1’, the simplified model of base-stabilized diborene (B=B double bond) synthesized by Robinson and coworkers,31 was also studied for comparison. According to DFT calculations, 1 has a planar structure, similar to its all-carbon isoelectronic species. For 1, the interaction energy (ΔEint) between the two fragments linked by the NC−B bond is −68.2 kcal mol−1, which is comparable to that of the L−B bond of 1’ (−85.2 kcal mol−1). We further performed energy decomposition analysis (EDA) for the NC−B bond of 1, whose orbital interaction was partitioned into different components with the method known as natural orbitals for chemical valence (NOCV).32 Shown in the inset of Figure 2 are the two major orbital interaction components for 1’s NC−B bond. The σ-donation of electron density from the N≡C subunit to B (N≡C→B) contributes the major bonding energy (−101.8 kcal mol−1), followed by the N≡C←B π-back donation (−19.0 kcal mol−1). Therefore, the NC−B bond is characterized as the donor-acceptor σ-bond in conjunction with a small fraction of π bond, suggesting the NCB unit to be a base-stabilized borylene.17,18 Its donor-acceptor bonding nature is confirmed by that it thermodynamically prefers heterolysis instead of homolysis, which have enthalpy changes of 68.2 and 283.8 kcal mol−1, respectively. Therefore, the NCB unit of 1 indeed adopts the bonding configuration of Figure 1c where all pz orbitals are singly occupied. The proton affinities of the B atoms in 1 and 1’ are −295.8 and −375.4 kcal mol−1, respectively,


5


Page 6 of 18

suggesting 1 to be even more stable than 1’ against protonation reactions. The above results suggest that the NCB unit can be used to build stable π-molecules, where all pz orbitals, including those of B and N, are singly occupied and electron donations occur only in the σ-bond frameworks. Me

Me

H

1

68.2 N

L B

L

B

1'

B

85.2 H

L: Me

Me

1

donor-acceptor -bonding (101.8)

-bonding (19.0)

N

N

Figure 2. Molecule 1 contains the NCB structural unit; 1’ is a simplified model of the base stabilized diborene, first reported by Robinson and co-workers.31 B atoms in 1 and 1’ have the same bonding configuration. The insert shows the main orbital interactions that contribute the chemical bond linking B and C in the NCB unit of 1. Me: Methyl. We then studied the possibility of implementing the NCB unit into two-dimensional (2D) πconjugated materials. To this end, one half of the C≡C−C units of 14,14,14-graphyne were replaced by the NCB units to form hybrid graphyne 2a (Figure 3a). Geometry optimization revealed the optimal geometric parameters a, b, and γ of 2a to be 4.91 Å, 4.91 Å, and 90.0°, respectively. The high kinetic stability of 2a was confirmed by ab initio molecular dynamic (AIMD) simulations, which suggested that its bond connectivity remained undestroyed at a high temperature of 1000 K for 2 ps (Figure S1 of the Supporting Information, SI). Unlike 14,14,14graphyne, which is gapless with Dirac cones,33,34 2a has an indirect bandgap of 0.63 eV at the PBE level of theory23 (Figure 2b and Figure S2a). Because PBE underestimates bandgaps, we recalculated its band structure using the hybrid density functional HSE06.35 This gap was


6

Page 7 of 18 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


enlarged to 1.02 eV with the HSE06 method. Shown in Figure 3c is the projected density of states (PDOS) for 2a. The pz orbitals of B, C, and N are all almost equally distributed above and below the Fermi level (EF), confirming that all the pz orbitals, including those of B and N dopants, are singly occupied. These results suggest that the NCB unit can also be used to build stable 2D π-materials with all pz orbitals singly occupied.

B a)

N b

B

c)

B

N

N 

B

b)

B N

C B N

B B

N B

a

N

B pz C pz N pz

N B

2a

d)

Figure 3. Structure and DFT calculated electronic properties for BN hybrid graphyne 2a with NCB bonding unit. (a) Structure with the unit cell marked; (b) electronic band structure; (c) PDOS; (d) the first Brillouin zone.

N a)

B N B N

N



B N N

b

B

B N

c) B pz C pz N pz

B N

B N C a

b)

B B N B

2b

d)


7


Page 8 of 18

Figure 4. Structure and DFT calculated electronic properties for NCB-violating structure 2b. (a) Structure with the unit cell marked; (b) electronic band structure; (c) PDOS; (d) the first Brillouin zone. Using NCB unit is the exclusive way to achieve hybrid π-materials where all atoms have singly-occupied pz orbitals. We optimized structures and calculated electronic configurations for five NCB-violating structures, 2b−2g, which were all derived from 14,14,14-graphyne by BN co-doping (Figure S3). Other NCB-violating BN co-doped structures based on α-, β-, γ-, and 6,6,12-graphyne have been reported before.36-40 Without the NCB units, all 2b−2f structures have doubly filled pz orbitals for N and empty pz for B. Taking 2b, where the B and N are directly bonded, as an example, the PDOS on B (N) pz is mainly distributed above (below) the Fermi level, indicating the pz is empty (doubly filled) (Figure 4). Similar to 2b, the doubly filled N pz and empty B pz are also true for 2c−2f (Figure S4). In contrast, 2g, another structure adopting the NCB unit, has singly occupied pz orbitals for both B and N atoms (Figure S5). Therefore, the NCB unit has the unique ability to achieve the singly-occupied pz for both B and N in hybrid πmaterials. The different pz orbital occupations of 2a and 2b are confirmed by their simulated scanning tunneling microscope (STM) images (Figure 5). These STM images reflect the unoccupied pz states near the EF. For pure carbon π-materials like 14,14,14-graphyne, all pz orbitals have the almost same singly pz occupation; therefore, all C atoms therein have the same brightness in the STM image (Figure 5a). Similarly, all atoms in 2a have almost the same brightness, in agreement with that all the pz orbitals therein are singly occupied as those in graphyne. In contrast, only one half atoms of 2b, namely, B and C atoms neighboring to N, are bright; the other half, namely, C and N neighboring to B, are dark (Figure 5b). The fluctuant brightness for atoms in 2b agrees


8

Page 9 of 18 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 its uneven pz occupation. These STM images straightforwardly evidence the ability of the NCB unit in maintaining the electronic configuration of graphyne upon BN co-doping.

c)

b)

a) C C C

C C N

C C C

C B C

C B C

C N C

Figure 5. DFT calculated STM images for 14,14,14-graphyne (a), 2a (b), and 2b (c). The energy windows for the simulations are EF to 0.1, 0.35, and 1.95 eV, respectively; some of the atoms are labelled. Encouragingly, 2a is the next lowest-energy structure among 2a through 2g, i.e., the different BN co-doping configurations of 14,14,14-graphyne. It is energetically higher than only 2c, the lowest-energy confirmation with B and N atoms clustering into B-N bonds,41,42 by 1.04 eV (Figure S3). The singly-occupied B and N pz orbitals and the relatively large thermodynamic stability of 2a can be ascribed to the rationality of the NCB building unit. Each N atom therein forms a chemically stable isocyanide −N≡C: subunit where the N pz is singly-occupied.43 As for B, it has the same bonding configuration as that of the base-stabilized B=B double bond,31 whose B pz is exactly singly-filled as that of Figure 1c. The chemical rationality of the NCB bonding pattern suggests the possibility to experimentally realize molecule 1 and 2D materials 2a using the bottom-up synthesis approach.44-46 Although all its atoms have singly-occupied pz orbitals as 14,14,14-graphyne, 2a is superior because of its sizable bandgap (1.02 eV with the HSE06 method) not owned by the former. Namely, the NCB unit is able to open the bandgap without inducing any empty or doubly filled


9


pz states. Therefore, the large carrier mobility, which is one of the most prominent merits of 2D π-conjugated carbon materials, will be most reserved in 2a. Indeed, the calculated electron mobility (μe) for 2a is higher than that of NCB-violating 2b by almost an order of magnitude (2.1 × 104 vs. 2.7 × 103 cm2 V−1 s−1 at 298 K). The highμe of 2a agrees with the experimental result that pyridinic N dopants at graphene edges, which have singly occupied pz orbitals, are in favor of conductivity.47 It also agrees with that graphene embedding clustering BN atoms possesses much smaller carrier mobilities because of the large ionic nature of the dopants and the electron scattering effect.48,49 The sizable bandgap and large carrier mobility of 2a suggests it is promising as high performance, post-silicon transistors.9 a)

b

1' B

1'

t,s



N

b)

e

1

t,s

B1' e

t,s

 1'

1'

N

e1

2' B

e = 0.000 t = 0.800 s = 0.025

N

t1,s1 1

t1,s1

t,s

B1'

b

2' B

t1,s1

t,s

N

t2,s2

2 e2 B

t1,s1 1'

a

1'

N

e1 = 0.280 e2 = 0.240 t1 = 0.780 t2 = 0.820 s1 = 0.022 s2 = 0.027

E  EF (eV)

E  EF (eV)

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 18

-graphyne

3a

Figure 6. Structures and DFT calculated electronic band structures for α-graphyne (a) and BN hybrid graphyne 3a with the NCB unit (b). Tight binding parameters that fit the DFT band structures are given below the structures; band dispersions obtained by DFT (black) and tight binding method (blue) are both shown in the band structures.


10

Page 11 of 18 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 NCB co-doping is also applicable to other graphynes for bandgap opening and homogenous pz orbital occupation. For example, substituting C≡C−C units of α-graphyne, which is gapless with Dirac cones (Figure 6a),50 by the N≡C−B leads to hybrid 2D π-material 3a with an open bandgap of 0.92 eV with the HSE06 method (0.54 eV with the PBE method, Figure 6b). As expected, all atoms in 3a, including B and N, have singly filled pz orbitals as in pristine αgraphyne (Figure S6). The simple hexagonal lattice of α-graphyne and 3a allows exploring the mechanism for the bandgap opening using the tight binding (TB) approximation.51 Using fitting parameters of Figure 6, the TB band structures agree well with the DFT calculated ones for αgraphyne and 3a. For α-graphyne, the onsite energies (e) at sites 1 and 1' are exactly the same because of the hexagonal symmetry, and so are the hoping energies (t) and overlap integrals (s) along the different directions. But these parameters, especially the onsite energies, become different in 3a. Therefore, the differentiation of onsite energies at sites 1 and 2, caused by the doping, is the main reason for the opening of bandgap in 3a. Because the two sites of 2a are also different (B vs. C), similar to 3a, such onsite energy differentiation also explains the bandgap opening in 2a. 4. CONCLUSIONS In summary, the NCB structural units can be implemented into graphynes (i.e., substituting graphyne’s C≡C−C structural units by the N≡C−B) to achieve kinetically stable BCN hybrid πmaterials. All atoms in these hybrid graphynes have singly occupied pz orbitals as in pure carbon graphynes; electron donations occur only in the σ-bond frameworks. The homogenous pz orbital occupation renders these hybrid graphynes considerably large carrier mobilities and simultaneously large bandgaps. Therefore, the NCB co-doping method provides a promising solution to opening a bandgap for graphynes without a severe detrition of their carrier mobilities.


11


Page 12 of 18

Because the NCB building unit is already experimentally achievable, the present results will stimulate the design and synthesis of these novel hybrid graphynes for electronic and photonic applications in the future. ASSOCIATED CONTENT Supporting Information The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jpcc.xxxxxxx. Snapshots of AIMD simulation for 2a, structures and electronic properties for other NCBviolating species (PDF) AUTHOR INFORMATION Notes The authors declare no competing financial interests. Corresponding Author *E-mail: [email protected] (X.G.) ACKNOWLEDGMENT This work was supported by the National Natural Science Foundation of China (NSFC) Project (No. 21773095) REFERENCES (1) Ashcroft, N. W.; Mermin, N. D.: Solid State Physics; Holt: New York, 1976. (2) 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. (3) Iijima, S. Helical Microtubules of Graphitic Carbon. Nature 1991, 354, 56-58.


12

Page 13 of 18 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


(4) Baughman, R. H.; Eckhardt, H.; Kertesz, M. Structure-Property Predictions for New Planar Forms of Carbon: Layered Phases Containing sp2 and sp Atoms. J. Chem. Phys. 1987, 87, 66876699. (5) Li, Y.; Xu, L.; Liu, H.; Li, Y. Graphdiyne and Graphyne: from Theoretical Predictions to Practical Construction. Chem. Soc. Rev. 2014, 43, 2572-2586. (6) Xu, X. Z.; Liu, C.; Sun, Z. H.; Cao, T.; Zhang, Z. H.; Wang, E. G.; Liu, Z. F.; Liu, K. H. Interfacial Engineering in Graphene Bandgap. Chem. Soc. Rev. 2018, 47, 3059-3099. (7) Inagaki, M.; Toyoda, M.; Soneda, Y.; Morishita, T. Nitrogen-Doped Carbon Materials. Carbon 2018, 132, 104-140. (8) Yu, S.-S.; Zheng, W.-T. Effect of N/B Doping on the Electronic and Field Emission Properties for Carbon Nanotubes, Carbon Nanocones, and Graphene Nanoribbons. Nanoscale 2010, 2, 1069-1082. (9) Schwierz, F. Graphene transistors. Nat. Nanotechnol. 2010, 5, 487-496. (10) Zhao, L. Y.; He, R.; Rim, K. T.; Schiros, T.; Kim, K. S.; Zhou, H.; Gutierrez, C.; Chockalingam, S. P.; Arguello, C. J.; Palova, L.; et al. Visualizing Individual Nitrogen Dopants in Monolayer Graphene. Science 2011, 333, 999-1003. (11) Nevidomskyy, A. H.; Csanyi, G.; Payne, M. C. Chemically Active Substitutional Nitrogen Impurity in Carbon Nanotubes. Phys. Rev. Lett. 2003, 91, 105502. (12) Panchakarla, L. S.; Subrahmanyam, K. S.; Saha, S. K.; Govindaraj, A.; Krishnamurthy, H. R.; Waghmare, U. V.; Rao, C. N. R. Synthesis, Structure, and Properties of Boron- and NitrogenDoped Graphene. Adv. Mater. 2009, 4726-4730.


13


Page 14 of 18

(13) Laref, A.; Ahmed, A.; Bin-Omran, S.; Luo, S. J. First-Principle Analysis of the Electronic and Optical Properties of Boron and Nitrogen Doped Carbon Mono-Layer Graphenes. Carbon 2015, 81, 179-192. (14) Gao, X.; Gao, X. J. Metal-like Boronic-Organic Frameworks: A Design and Computation. Inorg Chem 2017, 56, 2490-2495. (15) Lherbier, A.; Blase, X.; Niquet, Y. M.; Triozon, F.; Roche, S. Charge Transport in Chemically Doped 2D Graphene. Phys. Rev. Lett. 2008, 101, 036808. (16) Wang, H.; Maiyalagan, T.; Wang, X. Review on Recent Progress in Nitrogen-Doped Graphene: Synthesis, Characterization, and Its Potential Applications. ACS Catal. 2012, 2, 781794. (17) Braunschweig, H.; Dewhurst, R. D. Boron–Boron Multiple Bonding: From Charged to Neutral and Back Again. Organometallics 2014, 33, 6271-6277. (18) Wang, Y.; Robinson, G. H. Chemistry. Building a Lewis Base with Boron. Science 2011, 333, 530-531. (19) Tai, T. B.; Nguyen, M. T. Boron-Boron Multiple Bond in [B(NHC)]2: towards Stable and Aromatic [B(NHC)]n Rings. Angew. Chem. Int. Ed. 2013, 52, 4554-4557. (20) Kresse G.; Joubert D. From Ultrasoft Pseudopotentials to the Projector Augmented-Wave Method, Phys. Rev. B 1999, 59, 1758-1775. (21) Kresse G.; Furthmüller J. Efficient Iterative Schemes for Ab Initio Total-Energy Calculations Using a Plane-Wave Basis Set, Phys. Rev. B 1996, 54, 11169-11186. (22) Kresse, G.; Furthmüller J. Efficiency of Ab-Initio Total Energy Calculations for Metals and Semiconductors Using a Plane-Wave Basis Set, Comput. Mater. Sci. 1996, 6, 15-50.


14

Page 15 of 18 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


(23) Perdew J. P.; Burke K.; Ernzerhof M. Generalized Gradient Approximation Made Simple, Phys. Rev. Lett. 1996, 77, 3865-3866. (24) P.E. Blöchl, Projector Augmented-Wave Method, Phys. Rev. B 1994, 50, 17953. (25) Monkhorst H.J.; Pack J.D. Special Points for Brillouin-Zone Integrations, Phys. Rev. B 1976, 13, 5188-5192. (26). Bruzzone, S. & Fiori, G. Ab-Initio Simulations of Deformation Potentials and Electron Mobility in Chemically Modified Graphene and Two-Dimensional Hexagonal Boron-Nitride. Appl. Phys. Lett. 2011, 99, 2108. (27). Takagi, S.-i., Toriumi, A., Iwase, M.; Tango, H. On the Universality of Inversion Layer Mobility in Si MOSFET’s: Part I-Effects of Substrate Impurity Concentration. IEEE Trans. Electr. Dev. 1994, 41, 2357-2368. (28). Fiori, G. & Iannaccone, G. Multiscale Modeling for Graphene-Based Nanoscale Transistors. Proc. IEEE 2013, 101, 1653-1669. (29) Qiao, J..; Kong, X..; Hu, Z. X.; Yang, F.; Ji, W. High-Mobility Transport Anisotropy and Linear Dichroism in Few-Layer Black Phosphorus, Nat .Commun 2014, 5, 4475. (30) Chen, J.; Xi, J.;Wang, D.;Shuai, Z. Carrier Mobility in Graphyne Should Be Even Larger than That in Graphene: A Theoretical Prediction, J. Phys. Chem. Lett 2013, 5, 1443-1448. (31) Wang, Y.; Quillian, B.; Wei, P.; Wannere, C. S.; Xie, Y.; King, R. B.; Schaefer, H. F.; Schleyer, P. V.; Robinson, G. H. A Stable Neutral Diborene Containing a B = B Double Bond. J. Am. Chem. Soc. 2007, 129, 12412-12413. (32) Mitoraj, M. P.; Michalak, A.; Ziegler, T. A Combined Charge and Energy Decomposition Scheme for Bond Analysis. J. Chem. Theo. Comput. 2009, 5, 962-975.


15


Page 16 of 18

(33) Huang, H.; Duan, W.; Liu, Z. The Existence/Absence of Dirac Cones in Graphynes. New J. Phys. 2013, 15, 023004. (34) Enyashin, A. N.; Ivanovskii, A. L. Fluorographynes: Stability, Structural and Electronic Properties. Superlattice. Microst. 2013, 55, 75-82. (35) Heyd, J.; Scuseria, G. E.; Ernzerhof, M. Hybrid Functionals Based on a Screened Coulomb Potential. J. Chem. Phys. 2003, 118, 8207-8215. (36) Yun, J.; Zhang, Y.; Xu, M.; Yan, J.; Zhao, W.; Zhang, Z. DFT Study of the Effect of BN Pair Doping on the Electronic and Optical Properties of Graphyne Nanosheets. J. Mater. Sci. 2017, 52, 10294-10307. (37) Mu, Y.; Li, S.-D. Multiple Dirac Cones in BN Co-doped β-graphyne. J. Mater. Chem. C 2016, 4, 7339-7344. (38) Özçelik, V. O.; Ciraci, S. Size Dependence in the Stabilities and Electronic Properties of αGraphyne and Its Boron Nitride Analogue. J. Phys. Chem. C 2013, 117, 2175-2182. (39) Singh, N. B.; Bhattacharya, B.; Sarkar, U. A First Principle Study of Pristine and BN-doped Graphyne Family. Struct. Chem. 2014, 25, 1695-1710. (40) Chen, X.; Qiao, Q.; An, L.; Xia, D. Why Do Boron and Nitrogen Doped α- and γ-graphyne Exhibit Different Oxygen Reduction Mechanism? A First-Principles Study. J. Phys. Chem. C. 2015, 119, 11493-11498. (41) Schiros, T.; Nordlund, D.; Palova, L.; Zhao, L. Y.; Levendorf, M.; Jaye, C.; Reichman, D.; Park, J.; Hybertsen, M.; Pasupathy, A. Atomistic Interrogation of B-N Co-dopant Structures and Their Electronic Effects in Graphene. Acs Nano 2016, 10, 6574-6584. (42) Fan, X.; Shen, Z.; Liu, A. Q.; Kuo, J. L. Band Gap Opening of Graphene by Doping Small Boron Nitride Domains. Nanoscale 2012, 4, 2157-2165.


16

Page 17 of 18 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


(42) Sarapu, A. C.; Fenske, R. F. Bonding Properties of the Methyl Isocyanide Ligand. SingleCrystal X-ray Diffraction and Molecular Orbital Study of Bromotricarbonylbis(methyl isocyanide)manganese, Mn(CO)3(CNCH3)2Br. Inorg. Chem. 1972, 11, 3021-3025. (44) Dou, C.; Saito, S.; Matsuo, K.; Hisaki, I.; Yamaguchi, S. A Boron-Containing PAH as a Substructure of Boron-Doped Graphene. Angew. Chem. Int. Ed. 2012, 51, 12206-12210. (45) Jiang, L.; Niu, T.; Lu, X.; Dong, H.; Chen, W.; Liu, Y.; Hu, W.; Zhu, D. Low-Temperature, Bottom-Up Synthesis of Graphene via a Radical-Coupling Reaction. J. Am. Chem. Soc. 2013, 135, 9050-9054. (46) Matsui, K.; Oda, S.; Yoshiura, K.; Nakajima, K.; Yasuda, N.; Hatakeyama, T. One-Shot Multiple Borylation toward BN-Doped Nanographenes. J. Am. Chem. Soc. 2018, 140, 11951198. (47) Wang, X.; Li, X.; Zhang, L.; Yoon, Y.; Weber, P. K.; Wang, H.; Guo, J.; Dai, H. N-Doping of Graphene Through Electrothermal Reactions with Ammonia. Science 2009, 324, 768-771. (48) Chang, C.-K.; Kataria, S.; Kuo, C.-C.; Ganguly, A.; Wang, B.-Y.; Hwang, J.-Y.; Huang, K.J.; Yang, W.-H.; Wang, S.-B.; Chuang, C.-H.; et al. Band Gap Engineering of Chemical Vapor Deposited Graphene by in Situ BN Doping. ACS Nano 2013, 7, 1333-1341. (49) Ci, L.; Song, L.; Jin, C.; Jariwala, D.; Wu, D.; Li, Y.; Srivastava, A.; Wang, Z. F.; Storr, K.; Balicas, L.; et al. Atomic Layers of Hybridized Boron Nitride and Graphene Domains. Nat. Mater. 2010, 9, 430-435. (50) Malko, D.; Neiss, C.; Viñes, F.; Görling, A. Competition for Graphene: Graphynes with Direction-Dependent Dirac Cones. Phys. Rev. Lett. 2012, 108, 086804. (51) Zheng, J.-J.; Zhao, X.; Zhao, Y.; Gao, X. Tight-Tinding Description of Graphyne and Its Two-Dimensional Derivatives. J. Chem. Phys. 2013, 138, 244708.


17


Page 18 of 18

TOC GRAPHICS


18

Boron and Nitrogen Co-Doping of Graphynes without Inducing Empty

Recommend Documents