Two-Dimensional Stoichiometric Boron Oxides as a Versatile Platform

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Letter

Two-Dimensional Stoichiometric Boron Oxides as a Versatile Platform for Electronic Structure Engineering Ruiqi Zhang, Zhenyu Li, and Jinlong Yang J. Phys. Chem. Lett., Just Accepted Manuscript • DOI: 10.1021/acs.jpclett.7b01721 • Publication Date (Web): 25 Aug 2017 Downloaded from http://pubs.acs.org on August 27, 2017

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The Journal of Physical Chemistry Letters

Two-Dimensional Stoichiometric Boron Oxides as a Versatile Platform for Electronic Structure Engineering Ruiqi Zhang, Zhenyu Li* and Jinlong Yang * Hefei National Laboratory for Physical Sciences at the Microscale, Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China * Corresponding Author Email: [email protected]; [email protected]

ABSTRACT: Oxides of two dimensional (2D) atomic crystals have been widely studied due to their unique properties. In most 2D oxides, oxygen acts as a functional group, which makes it difficult to control the degree of oxidation. Since borophene is an electron-deficient system, it is expected that oxygen will be intrinsically incorporated into the basal plane of borophene, forming stoichiometric 2D boron oxides (BO) structures. By using first-principles global optimization, we systematically explore structures and properties of 2D BO systems with welldefined degrees of oxidation. Stable B-O-B and OB3 tetrahedron structure motifs are identified in these structures. Interesting properties, such as strong linear dichroism, Dirac node-line (DNL) semi-metallicity, and negative differential resistance, have been predicted for these systems. Our results demonstrate that 2D BO represents a versatile platform for electronic structure engineering via tuning the stoichiometric degree of oxidation, which leads to various technological applications.

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TOC GRAPHICS

Since the successful isolation of graphene in 20041, two-dimensional (2D) atomic crystals have attracted significant research interests due to their unanticipated and fascinating properties2–5. Compared with their bulk counterparts, 2D materials have favorable oxidation kinetics due to the predominance of surface atoms.6 Oxidation provides a useful mean to tune the physical and chemical properties of 2D materials7,8. For example, properties of graphene oxides (GO) are used in various applications including energy storage, filtration, actuation, sensing, electronics, and so on9–14. In addition, oxides of other 2D materials, such as hexagonal boron-nitride,6,15,16 phosphorene,17–19 and blue phosphorene20 show great potentials in nanoscale device applications. In all these oxides, oxygen is bound to the basal plane of 2D atomic crystals as a functional group. In such structures, the degree of oxidation is difficult to be exactly controlled. As an example, GO turns out to be an amorphous material12–14,21,22. Such materials are expected to be easily further oxidized or reduced in different chemical environment, which limits their stabilities. Therefore, it is desirable to make the oxygen be fully incorporated into the basal plane


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of the 2D atomic crystals. For this purpose, borophene is an interesting candidate since it is electron deficient which makes B-B bonds unfavorable. Oxygen incorporation is expected to form more B-O bonds and thus energetically favorable. Such an incorporation trend has been demonstrated experimentally for other external atoms.23 Various structures of borophene have been predicted in theory24–28. Although experimentally challenging23,26,29,30, various 2D boron structures, such as borophene, β12 and χ3 sheet, and monolayer γ-B28 31–33 have been synthesized. All these 2D boron structures are not chemically stable as free standing sheets and are expected to be oxidized in air, which is already evidenced by the experimental observation of B-O infrared peak32 and theoretical prediction of spontaneous dissociation of oxygen molecules on the borophene sheet29. At the same time, preparations of crystalline boron oxide thin films34 and ordered boron oxide nanostructures35 have been realized in experiments. All these results call for a systematic study of structures and properties of 2D boron oxides (BO). In the present Letter, we perform a structure global search36 to predict the lowest energy structures of 2D BO with different oxygen concentrations using the particle-swarm optimization (PSO) algorithm37 combined with first-principles calculations. We consider B:O ratios ranging from 8:1 to 4:1.

It is confirmed that oxygen in the predicted stable structures are fully

incorporated into the basal plane of borophene instead of adsorbed on it. B-O-B and OB3 tetrahedron structure motifs are identified at different oxygen concentrations. Importantly, based on these stable stoichiometric structures, various interesting properties are predicted.

For

example, B4O is a semiconductor with a quasi-direct band gap of 1.24 eV. Due to its strongly anisotropic carrier mobility and optical properties, monolayer B4O can be used as a 2D polarization sensitive photodetector across a very broad bandwidth from 1.40 (~890 nm) to 3.25 eV (~380 nm). Notice that previous potential 2D broadband photodetector materials either are


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not stable in ambient environment or have a relatively low mobility, such as phosphorene18,38–40 and 2D ReS241. B6O is a 2D Dirac node-line (DNL) semimetal. The DNL semimetal is an important kind of topological semimetal,42,43 which can be used to

achieve

2D

high-

temperature super-conductivity44. B8O, B7O, and B5O are strongly anisotropic metals and show negative differential resistance (NDR) characters. NDR is a phenomenon widely observed in molecular45–49 and nano50 junction systems. Due to the complexity to construct junction system,51 it is very attractive to realize NDR in a pristine material as shown here. These results open a new avenue to develop new electronic applications by using stoichiometric 2D oxides.

Our PSO simulations predict different global minimum structure motifs for different oxygen concentrations (Figure 1). Both atom positions and lattice constants are fully optimized. More computational details are available in the Supporting Information. Among them, B8O, B7O and B5O have structures with triangular lattices and hexagonal holes. Holes with all edge atoms being B are called B-B hexagonal holes, while those with both B and O edge atoms are named B-O hexagonal holes. In B8O, both B-B and B-O hexagonal holes exist. However, in B7O and B5O, there are only B-O hexagonal holes. B6O has a totally different sandwich structure, where a layer of O atoms is between two layers of buckled B triangular lattices. For B4O, ribbons with a triangular lattice and B-O hexagonal holes are connected by B-O squares, where all the O atoms are surrounded by three B atoms. All these 2D BO sheets have non-planar structures. B6O has the largest thickness of 4.592 Å and B5O has the smallest thickness of 0.137 Å. Except B4O, all these BO structures contain B-O-B motifs, which can be viewed as that the B-B hexagonal holes in borophene are broken with O inserted into them. When the oxygen concentration is one forth, tetrahedrons consisting of one boron and three oxygen atoms appears. Such structure motifs of


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2D BO are different from previous oxides of 2D atomic crystals, such as graphene and phosphorene. In both graphene and phosphorene oxides, the basic structure model is O adsorption on the basal plane.18,52

Figure 1. Top and side views of the lowest-energy structures of (a) B8O, (b) B7O, (c) B5O, (d) B6O and (e) B4O. Green and red balls represent B atoms and O atoms, respectively. The shapes of unit cells are labeled with red solid line.

To evaluate the stabilities of these predicted 2D BO structures, we calculate the average

binding energy per boron atom, which is defined as /, where , , and are the total energies of a single B atom in borophene, the O2 molecule, and one unit cell, respectively. As listed in Table 1, the average binding energy per boron atom are all positive, indicating these nanosheets are energetically stable against decomposition into


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borophene and O2 molecule. What is more, the binding energy increases with the increase of oxygen concentration.

Table 1. Lattice Constant, Symmetry Group (SG), and Binding Energy (Eb) for 2D BO Sheets. Phase

a (Å)

b (Å)

c (Å)

SG

Eb (eV)

B8O

9.427

2.888

20.000

P2/M

0.445

B7O

7.732

2.883

20.000

PMM2

0.470

B6O

2.884

2.884

20.000

P6/MMM

0.638

B5O

6.168

2.907

20.000

PMM2

0.622

B4O

9.218

2.799

20.000

P21/M

0.891

Notice that binding energy is not the only parameter to describe stability in reality. To test the dynamic stability of monolayer BO sheets, we compute their lattice dynamics. Our calculated phonon band structures demonstrate that these structures are dynamically stable (Figure S1). Especially, the highest frequency of monolayer BO reach up to about 1400 cm-1, which is much higher than the highest frequency of 459 cm-1 in phosphorene53 and 473 cm-1 in MoS2 monolayer 54

, indicating strong B-B and B-O bonds in these monolayer sheets. At the same time, stability of

these predicted BO structures is also assessed by ab initio molecular dynamics (AIMD). Our results show that all these BO structures except B4O are stable at 300K (Figure S2). It is interesting to note that B4O has the highest binding energy, which indicate an overall strong binding. However, stability here is determined by the weakest bond. In fact, B-O bonds in B4O are longer than those in other BO structures.


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Electronic and Optical Properties of B4O. The band structure of B4O calculated with the HSE06 hybrid functional are shown in Figure 2 (a). There is a quasi-direct band gap of 1.24 eV. The position of conduction band minimum (CBM) is located at (0.500, 0.425, 0.000), while valence band maximum (VBM) is located at (0.000, 0.425, 0.000). The difference between direct band gap and indirect one is only 35 meV. In addition, the band structure near the CBM and VBM exhibit strong dispersion from X (0.5, 0.0, 0.0) to S (0.5, 0.5, 0.0) and Y (0.0, 0.5, 0.0) to Γ (0.0, 0.0, 0.0)), indicating that the 2D B4O may have relatively high carrier mobility along the b direction. At the same time, almost straight bands present from S (0.5, 0.5, 0.0) to Y (0.0, 0.5, 0.0), suggesting that B4O has low carrier mobility along the a direction. Carrier mobility of monolayer B4O is predicted by calculating deformation potential (DP) constant (E1), 2D elastic modulus (C2D) and effective mass (See Supporting Information). As shown in Table 2, the 2D modulus along a is slightly bigger than that along the b direction, which can be explained by different chemical bonds strengths along different directions. Actually, the length of B-B bonds along both directions are almost identical, while the length of B-O bonds are 1.531 Å along a direction and 1.605 Å along b direction. In addition, the effective mass shows an obviously anisotropic feature. For electrons, me* along the a direction is almost 92 times greater than that in the b direction. These results can be well explained by the charge-density plot of CBM and VBM in Figure 2(c), where both CBM and VBM are localized in the a direction while delocalized in the b direction. As a result of the strongly anisotropic effective mass, the carrier mobility is also highly anisotropic. In the b direction, the electron mobility is 4.132×103 cm2/V/s, which is about 2.1×104 times larger than that in the a direction. And, the hole mobility is 1.050×103 cm2/V/s in


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the b direction which is about 5.6×102 times bigger than that in the a direction. Thus, electrons and holes will prefer to transport along the b direction instead of the a direction. Optical absorption spectra of B4O are also calculated. The quasi-direct band gap transition gives a large light absorption in infrared and visible light region. Two very different absorption spectra for light polarized along the a and b directions are shown in Figure 2(b). A strong anisotropy is predicted in a wide range from 1.40 eV (~890 nm) to 3.25 eV (~380 nm). The band edge along the b direction is close to the overall band gap while the band edge along the a direction is close to the band gap along this direction. Strong transport anisotropy and linear dichroism make B4O very attractive for 2D polarization sensitive photodetector after phosphorene38 and layered ReS2.41


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Figure 2. (a) Band structure of B4O. Locations of VBM and CBM are marked by red circles. (b) Calculated optical absorption spectra of monolayer B4O for light incident in the c direction and polarized along the a and b directions. Sites for first absorption peak along different directions are marked by arrows. (c) The charge density corresponding to the CBM and VBM, respectively. The isovalue is 0.008 e/Bohr3.

Table 2. Calculated DP Constant (E1), 2D Elastic Modulus (C2D), Effective Mass (m*), and Electron and Hole Mobility (µ) along Two Directions of B4O at 300 K

carrier (direction)

E1(eV)

C2D(J/m2)

m*(me)

µ(cm2/V/s)

e (a)

2.054

87.393

12.354

0.1930

h (a)

1.222

87.393

6.660

1.873

e (b)

1.190

74.003

0.134

4.132× 103

h (b)

2.081

74.003

0.152

1.050× 103

Electronic Properties of B6O. Electronic structure of 2D B6O sheet is depicted in Figure 3. In the band structure along high-symmetry lines (Figure 3a), the valence and conduction bands cross each other at (0.305, 0.305, 0.000) along Γ-K and (0.366, 0.268, 0.000) along K-M. Actually, around the K point in the Brillouin zone, there is an entire elliptic DNL (Figure 3c). This is different from some Dirac 2D materials, like graphene3, γ-borophene25, and 2D P6/mmm boron28 with a Dirac cone near the Fermi Level. Notice that, although 3D DNL state have been predicted in several systems including pure alkali earth metals55, antiperovskite Cu3PdN56, and a hyperhoneycomb lattice57, 2D DNL semimetal is rarely studied58. The Fermi velocities in 2D


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B6O are estimated according to ≈ /. The outer (inner) radial velocities of the states on the nodal line have their largest value of 0.61×106 m/s (0.50×106 m/s) along the high symmetry line Γ–K and their lowest value of 0.26×106 m/s (0.22×106m/s) along the line K-M, compared to the corresponding value (0.82×106m/s) in graphene.25 These unique Dirac ring electron states may give B6O excellent electronic transport properties.29 To get insight into the origin of DNL, we check the real-space density of four sets of states around the DNL ((a1 ,a2 ), (b1 ,b2 ), (c1 ,c2 ), (d1 ,d2 ) in Figure 3 (a). It is clearly that a1, b2, c2 and d1 are π states, while a2 , b1 , c1 and d2 are π* states (Figure S3). Therefore, there is a band inversion at the K point, which induces the DNL band crossing at the Fermi level. At the same time, due to the light mass of B and O, B6O spin-orbit coupling (SOC) effect is rather weak and not affect the electronic band structure (Figure S4).


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Figure 3. (a) Band structure and (b) DOS of B6O. (c) 3D band structure for bands around the Fermi level. (d) Γ (0.0, 0.0, 0.0), M (0.5, 0.5, 0.0), and K (1/3, 1/3, 0.0) refer to special points in the first Brillouin zone.

Electronic and Transport Properties of B7O. Based on our results, B8O, B7O, and B5O are all metallic. Interestingly, all of them show strong anisotropy. For example, as indicated by the band structure shown in Figure 4 (a), the transport along b direction is expected to be much better than along a direction for B7O. To quantitatively investigate such an anisotropy, we perform firstprinciples calculations combined with non-equilibrium Green’s function method to explicitly


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calculate the conductivity (See Supporting Information). The calculated zero-bias transmission functions of B7O along different directions are plotted in Figure S5.

It is clear that the

transmission coefficients along b direction are significantly larger than that along a direction. The strongly anisotropic transport properties of B7O can be well explained by the charge density around the Fermi level, as shown in Figure 4 (b), where there is a strong overlapping of wave function in b direction while the overlap becomes very weak in a direction. Interestingly, as shown in Figure 4(d), an NDR character is observed in transport along a direction with a high current peak-to-valley ratio (PVR) ~1400. To understand the mechanism, we plot the bias-dependent transmission spectra in Figure 5. The transmission decrease with the increase of the bias voltage, which is a result of the reduced delocalization of the eigen-orbitals of the molecular junctions projected self-consistent Hamiltonian (MPSH) (Figure S6-S7). As shown in Figure 5, with the increase of the bias voltage the energy window becomes wider which typically includes more states which can contribute to the transport. Here, competition between the increase of the bias energy window and the decrease of transmission leads to the NDR effect. Notice that although decrease of transmission with increase of bias voltage is not a unique property, NDR based on its competition with bias window increase has not been reported before. Similar NDR phenomenon is also observed in B8O and B5O (see Figure S8-S14). Since 2D materials may play an important role in the next generation of electronics, our findings will stimulate more experimental and theoretical studies of NDR phenomenon in 2D materials.


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Figure 4. (a) Band structure of B7O. (b) Charge density around the Fermi level in the energy range from -0.5 eV to 0.5 eV. The isovalue is 0.004 e/Bohr3. Calculated I-V curves of B7O along (c) b and (d) a directions.

Figure 5. The Calculated transmission spectra of B7O along a direction at (a) 0.0 V, (b) 0.1 V (c) 0.45 V and (d) 0.95 V. The red short vertical lines stand for positions of MPSH eigenvalues. Shadow areas are the energy window where states can contribute to the transport.


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In conclusion, using a global optimization method, we have systematically studied structures of 2D BO. These lowest energy structures follow a new construction rule by incorporating oxygen into the 2D plane instead of adsorbing oxygen on surface as a functional group. Such a structure model leads to stoichiometric structures with a well-defined degree of oxidation. As a result, 2D BO can be served as a very attractive platform for electronic structure engineering. B4O has been demonstrated to be a semiconductor with a moderate quasi-direct band gap. It is a strongly anisotropic 2D material for optoelectronics and electronics. The ground state structure of B6O is sandwich like. This structure exhibits Dirac loop near the Fermi level and has a Fermi velocity as high as 0.61×106 m/s. B8O, B7O and B5O have nonplanar structures and they are metallic also with a strong conductivity anisotropy. More importantly, intrinsic NDR effect without requiring to construct hetero-junctions has been observed with the current PVR up to ~1400. These interesting properties make 2D BO structures have great potentials to be applied in nanoelectronic applications. Structures predicted here are all dynamically stable, which encourages further experimental efforts to synthesize them.

ASSOCIATED CONTENT


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Supporting Information Available: Computational details; phonon band structures; structural snapshots of AIMD trajectory; charge density; transmission, I-V curves, and perturbed molecular orbitals.

AUTHOR INFORMATION Corresponding Author *E-mail: [email protected]; [email protected] ORCID Ruiqi Zhang: 0000-0002-7820-6020 Zhenyu Li: 0000-0003-2112-9834 Jinlong Yang: 0000-0002-5651-5340 Notes The authors declare no competing financial interests. ACKNOWLEDGMENTS This work is partially supported by the National Key Research and Development Program (Grants No. 2016YFA0200604) and by the National Natural Science Foundation of China NSFC (Grants No. 21421063, 91021004, 21233007). We used computational resources of Supercomputing Center of University of Science and Technology of China, Supercomputing Center of Chinese Academy of Sciences, Tianjin and Shanghai Supercomputer Centers. The authors would like to thank Professor Jing Huang and Doctors Bo Fu, Zhao Liu and Lu Zhang for valuable discussions.


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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 (5696), 666–669.

(2)

Geim, A. K.; Novoselov, K. S. The Rise of Graphene. Nat. Mater. 2007, 6, 183–191.

(3)

Castro Neto, A. H.; Guinea, F.; Peres, N. M. R.; Novoselov, K. S.; Geim, A. K. The Electronic Properties of Graphene. Rev. Mod. Phys. 2009, 81, 109–162.

(4)

Mas-Ballesté, R.; Gómez-Navarro, C.; Gómez-Herrero, J.; Zamora, F. 2D Materials: To Graphene and beyond. Nanoscale 2011, 3, 20–30.

(5)

Bhimanapati, G. R.; Lin, Z.; Meunier, V.; Jung, Y.; Cha, J.; Das, S.; Xiao, D.; Son, Y.; Strano, M. S.; Cooper, V. R.; et al. Recent Advances in Two-Dimensional Materials beyond Graphene. ACS Nano 2015, 9, 11509–11539.

(6)

Li, L. H.; Cervenka, J.; Watanabe, K.; Taniguchi, T.; Chen, Y. Strong Oxidation Resistance of Atomically Thin Boron Nitride Nanosheets. ACS Nano 2014, 8, 1457–1462.

(7)

Butler, S. Z.; Hollen, S. M.; Cao, L.; Cui, Y.; Gupta, J. A.; Gutiérrez, H. R.; Heinz, T. F.; Hong, S. S.; Huang, J.; Ismach, A. F.; et al. Progress, Challenges, and Opportunities in Two-Dimensional Materials Beyond Graphene. ACS Nano 2013, 7, 2898–2926.

(8)

Georgakilas, V.; Tiwari, J. N.; Kemp, K. C.; Perman, J. A.; Bourlinos, A. B.; Kim, K. S.; Zboril, R. Noncovalent Functionalization of Graphene and Graphene Oxide for Energy


16

Page 17 of 22

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


Materials, Biosensing, Catalytic, and Biomedical Applications. Chem. Rev. 2016, 116, 5464–5519. (9)

Zhang, W.; Carravetta, V.; Li, Z.; Luo, Y.; Yang, J. Oxidation States of Graphene: Insights from Computational Spectroscopy. J. Chem. Phys. 2009, 131, 244505.

(10)

Li, Z.; Zhang, W.; Luo, Y.; Yang, J.; Hou, J. G. How Graphene Is Cut upon Oxidation? J. Am. Chem. Soc. 2009, 131, 6320–6321.

(11)

Chang, Z.; Deng, J.; Chandrakumara, G. G.; Yan, W.; Liu, J. Z. Two-Dimensional Shape Memory Graphene Oxide. Nat. Commun. 2016, 7, 11972.

(12)

Chen, D.; Feng, H.; Li, J. Graphene Oxide: Preparation, Functionalization, and Electrochemical Applications. Chem. Rev. 2012, 112, 6027–6053.

(13)

Zhu, Y.; Murali, S.; Cai, W.; Li, X.; Suk, J. W.; Potts, J. R.; Ruoff, R. S. Graphene and Graphene Oxide: Synthesis, Properties, and Applications. Adv. Mater. 2010, 22, 3906– 3924.

(14)

Huang, B.; Xiang, H.; Xu, Q.; Wei, S.-H. Overcoming the Phase Inhomogeneity in Chemically Functionalized Graphene: The Case of Graphene Oxides. Phys. Rev. Lett. 2013, 110, 85501.

(15)

Zhao, Y.; Wu, X.; Yang, J.; Zeng, X. C. Oxidation of a Two-Dimensional Hexagonal Boron Nitride Monolayer: A First-Principles Study. Phys. Chem. Chem. Phys. 2012, 14, 5545.

(16)

Guo, Y.; Guo, W. Insulating to Metallic Transition of an Oxidized Boron Nitride Nanosheet Coating by Tuning Surface Oxygen Adsorption. Nanoscale 2014, 6, 37313736.


17


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

(17)

Page 18 of 22

Wang, G.; Pandey, R.; Karna, S. P. Phosphorene Oxide: Stability and Electronic Properties of a Novel Two-Dimensional Material. Nanoscale 2015, 7, 524–531.

(18)

Luo, W.; Xiang, H. Two-Dimensional Phosphorus Oxides as Energy and Information Materials. Angew. Chem. Int. Ed. 2016, 55, 8575–8580.

(19)

Ziletti, A.; Carvalho, A.; Trevisanutto, P. E.; Campbell, D. K.; Coker, D. F.; Castro Neto, A. H. Phosphorene Oxides: Bandgap Engineering of Phosphorene by Oxidation. Phys. Rev. B 2015, 91, 85407.

(20)

Zhu, L.; Wang, S.-S.; Guan, S.; Liu, Y.; Zhang, T.; Chen, G.; Yang, S. A. Blue Phosphorene Oxide: Strain-Tunable Quantum Phase Transitions and Novel 2D Emergent Fermions. Nano Lett. 2016, 16, 6548–6554.

(21)

Bagri, A.; Mattevi, C.; Acik, M.; Chabal, Y. J.; Chhowalla, M.; Shenoy, V. B. Structural Evolution during the Reduction of Chemically Derived Graphene Oxide. Nat. Chem. 2010, 2, 581–587.

(22)

Dave, S. H.; Gong, C.; Robertson, A. W.; Warner, J. H.; Grossman, J. C. Chemistry and Structure of Graphene Oxide via Direct Imaging. ACS Nano 2016, 10, 7515–7522.

(23)

Li, W.-L.; Jian, T.; Chen, X.; Chen, T.-T.; Lopez, G. V.; Li, J.; Wang, L.-S. The Planar CoB18− Cluster as a Motif for Metallo-Borophenes. Angew. Chem. Int. Ed. 2016, 55, 7358–7363.

(24)

Wu, X.; Dai, J.; Zhao, Y.; Zhuo, Z.; Yang, J.; Zeng, X. C. Two-Dimensional Boron Monolayer Sheets. ACS Nano 2012, 6, 7443–7453.

(25)

Zhou, X.-F.; Dong, X.; Oganov, A. R.; Zhu, Q.; Tian, Y.; Wang, H.-T. Semimetallic TwoDimensional Boron Allotrope with Massless Dirac Fermions. Phys. Rev. Lett. 2014, 112, 85502.


18

Page 19 of 22

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


(26)

Zhang, Z.; Yang, Y.; Gao, G.; Yakobson, B. I. Two-Dimensional Boron Monolayers Mediated by Metal Substrates. Angew. Chem. Int. Ed. 2015, 54, 13022–13026.

(27)

Zhou, X.-F.; Oganov, A. R.; Wang, Z.; Popov, I. A.; Boldyrev, A. I.; Wang, H.-T. TwoDimensional Magnetic Boron. Phys. Rev. B 2016, 93, 85406.

(28)

Ma, F.; Jiao, Y.; Gao, G.; Gu, Y.; Bilic, A.; Chen, Z.; Du, A. Graphene-like TwoDimensional Ionic Boron with Double Dirac Cones at Ambient Condition. Nano Lett. 2016, 16, 3022–3028.

(29)

Jiao, Y.; Ma, F.; Bell, J.; Bilic, A.; Du, A. Two-Dimensional Boron Hydride Sheets: High Stability, Massless Dirac Fermions, and Excellent Mechanical Properties. Angew. Chem. Int. Ed. 2016, 55, 10292–10295.

(30)

Xu, S.; Zhao, Y.; Liao, J.; Yang, X.; Xu, H. The Nucleation and Growth of Borophene on the Ag (111) Surface. Nano Res. 2016, 9, 2616–2622.

(31)

Mannix, A. J.; Zhou, X.-F.; Kiraly, B.; Wood, J. D.; Alducin, D.; Myers, B. D.; Liu, X.; Fisher, B. L.; Santiago, U.; Guest, J. R.; et al. Synthesis of Borophenes: Anisotropic, TwoDimensional Boron Polymorphs. Science 2015, 350, 1513–1516.

(32)

Feng, B.; Zhang, J.; Zhong, Q.; Li, W.; Li, S.; Li, H.; Cheng, P.; Meng, S.; Chen, L.; Wu, K. Experimental Realization of Two-Dimensional Boron Sheets. Nat. Chem. 2016, 8, 563–568.

(33)

Tai, G.; Hu, T.; Zhou, Y.; Wang, X.; Kong, J.; Zeng, T.; You, Y.; Wang, Q. Synthesis of Atomically Thin Boron Films on Copper Foils. Angew. Chem. Int. Ed. 2015, 54, 15473– 15477.

(34)

Putkonen, M.; Niinistö, L. Atomic Layer Deposition of B2O3 Thin Films at Room Temperature. Thin Solid Films 2006, 514, 145–149.


19


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

(35)

Page 20 of 22

Ma, R.; Bando, Y. Self-Assembled Array of Boron Oxide Nanowires on Mg Surface. Chem. Phys. Lett. 2003, 374, 358–361.

(36)

Luo, X.; Yang, J.; Liu, H.; Wu, X.; Wang, Y.; Ma, Y.; Wei, S.-H.; Gong, X.; Xiang, H. Predicting Two-Dimensional Boron–Carbon Compounds by the Global Optimization Method. J. Am. Chem. Soc. 2011, 133, 16285–16290.

(37)

Wang, Y.; Lv, J.; Zhu, L.; Ma, Y. Crystal Structure Prediction via Particle-Swarm Optimization. Phys. Rev. B 2010, 82, 94116.

(38)

Yuan, H.; Liu, X.; Afshinmanesh, F.; Li, W.; Xu, G.; Sun, J.; Lian, B.; Curto, A. G.; Ye, G.; Hikita, Y.; et al. Polarization-Sensitive Broadband Photodetector Using a Black Phosphorus Vertical P–n Junction. Nat. Nanotechnol. 2015, 10, 707–713.

(39)

Ziletti, A.; Carvalho, A.; Campbell, D. K.; Coker, D. F.; Castro Neto, A. H. Oxygen Defects in Phosphorene. Phys. Rev. Lett. 2015, 114, 46801.

(40)

Island, J. O.; Steele, G. A.; Zant, H. S. J. van der; Castellanos-Gomez, A. Environmental Instability of Few-Layer Black Phosphorus. 2D Mater. 2015, 2, 011002.

(41)

Liu, F.; Zheng, S.; He, X.; Chaturvedi, A.; He, J.; Chow, W. L.; Mion, T. R.; Wang, X.; Zhou, J.; Fu, Q.; et al. Highly Sensitive Detection of Polarized Light Using Anisotropic 2D ReS2. Adv. Funct. Mater. 2016, 26, 1169–1177.

(42)

Ryu, S.; Hatsugai, Y. Topological Origin of Zero-Energy Edge States in Particle-Hole Symmetric Systems. Phys. Rev. Lett. 2002, 89, 77002.

(43)

Burkov, A. A.; Hook, M. D.; Balents, L. Topological Nodal Semimetals. Phys. Rev. B 2011, 84, 235126.

(44)

Yu, R.; Fang, Z.; Dai, X.; Weng, H. Topological Nodal Line Semimetals Predicted from First-Principles Calculations. Front. Phys. 2017, 12, 127202.


20

Page 21 of 22

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


(45)

Chen, L.; Hu, Z.; Zhao, A.; Wang, B.; Luo, Y.; Yang, J.; Hou, J. G. Mechanism for Negative Differential Resistance in Molecular Electronic Devices: Local Orbital Symmetry Matching. Phys. Rev. Lett. 2007, 99, 146803.

(46)

Pati, R.; McClain, M.; Bandyopadhyay, A. Origin of Negative Differential Resistance in a Strongly Coupled Single Molecule-Metal Junction Device. Phys. Rev. Lett. 2008, 100, 246801.

(47)

Li, Z.; Li, B.; Yang, J.; Hou, J. G. Single-Molecule Chemistry of Metal Phthalocyanine on Noble Metal Surfaces. Acc. Chem. Res. 2010, 43, 954–962.

(48)

Huang, J.; Wang, W.; Li, Q.; Yang, J. Negative Differential Resistance Devices by Using N-Doped Graphene Nanoribbons. J. Chem. Phys. 2014, 140, 164703.

(49)

Huang, J.; Xie, R.; Wang, W.; Li, Q.; Yang, J. Coherent Transport through SpinCrossover Magnet Fe2 Complexes. Nanoscale 2016, 8, 609–616.

(50)

Ren, H.; Li, Q.-X.; Luo, Y.; Yang, J. Graphene Nanoribbon as a Negative Differential Resistance Device. Appl. Phys. Lett. 2009, 94, 173110.

(51)

Sharma, P.; Bernard, L. S.; Bazigos, A.; Magrez, A.; Ionescu, A. M. Room-Temperature Negative Differential Resistance in Graphene Field Effect Transistors: Experiments and Theory. ACS Nano 2015, 9, 620–625.

(52)

Wang, L.; Sun, Y. Y.; Lee, K.; West, D.; Chen, Z. F.; Zhao, J. J.; Zhang, S. B. Stability of Graphene Oxide Phases from First-Principles Calculations. Phys. Rev. B 2010, 82, 161406.

(53)

Sa, B.; Li, Y.; Qi, J.; Ahuja, R.; Sun, Z. Strain Engineering for Phosphorene: The Potential Application as a Photocatalyst. J. Phys. Chem. C 2014, 118, 26560–26568.


21


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

(54)

Page 22 of 22

Molina-Sánchez, A.; Wirtz, L. Phonons in Single-Layer and Few-Layer MoS2 and WS2. Phys. Rev. B 2011, 84, 155413.

(55)

Li, R.; Ma, H.; Cheng, X.; Wang, S.; Li, D.; Zhang, Z.; Li, Y.; Chen, X.-Q. Dirac Node Lines in Pure Alkali Earth Metals. Phys. Rev. Lett. 2016, 117, 96401.

(56)

Yu, R.; Weng, H.; Fang, Z.; Dai, X.; Hu, X. Topological Node-Line Semimetal and Dirac Semimetal State in Antiperovskite Cu3PdN. Phys. Rev. Lett. 2015, 115, 36807.

(57)

Mullen, K.; Uchoa, B.; Glatzhofer, D. T. Line of Dirac Nodes in Hyperhoneycomb Lattices. Phys. Rev. Lett. 2015, 115, 26403.

(58)

Lu, J.-L.; Luo, W.; Li, X.-Y.; Yang, S.-Q.; Cao, J.-X.; Gong, X.-G.; Xiang, H.-J. TwoDimensional Node-Line Semimetals in a Honeycomb-Kagome Lattic. Chin. Phys. Lett. 2017, 34, 057302.


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