Electronic Structure and Carrier Mobilities of Arsenene and Antimonene Nanoribbons: A First-Principle Study
© Wang and Ding. 2015
Received: 3 March 2015
Accepted: 25 May 2015
Published: 4 June 2015
Arsenene and antimonene, i.e. two-dimensional (2D) As and Sb monolayers, are the recently proposed cousins of phosphorene (Angew. Chem. Int. Ed., 54, 3112 (2015)). Through first-principle calculations, we systematically investigate electronic and transport properties of the corresponding As and Sb nanoribbons, which are cut from the arsenene and antimonene nanosheets. We find that different from the 2D systems, band features of As and Sb nanoribbons are dependent on edge shapes. All armchair As/Sb nanoribbons keep the indirect band gap feature, while the zigzag ones transfer to direct semiconductors. Quantum confinement in nanoribbons enhances the gap sizes, for which both the armchair and zigzag ones have a gap scaling rule inversely proportional to the ribbon width. Comparing to phosphorene, the large deformation potential constants in the As and Sb nanoribbons cause small carrier mobilities in the orders of magnitude of 101–102 cm2/Vs. Our study demonstrates that the nanostructures of group-Vb elements would possess different electronic properties for the P, As, and Sb ones, which have diverse potential applications for nanoelectronics and nanodevices.
Since the discovery of phosphorene, two-dimensional (2D) group-V nanostructures have attracted lots of interests from physicists, chemists, and material scientists [1–5]. The 2D phosphorene nanosheet, i.e. the black-P monolayer, is a direct semiconductor with a high hole mobility comparable to graphene . When cut into nanoribbons, both the zigzag and armchair black-P nanoribbons (zPNRs, aPNRs) keep the direct band gap feature, which maintain high carrier mobilities akin to the 2D nanosheet [7–12]. The quantum confinement effects in nanoribbons further enhance the band gaps of PNRs, whose gap sizes are monotonously decreased with the increasing ribbon width [13–16].
Very recently, arsenene and antimonene, which are single-atom-thick layers of arsenic and antimony, have been proposed as new members of group-V nanostructures [17–21]. These As/Sb nanosheets have a different buckling structure from phosphorene, which prefer to the blue-P-like structure rather than the black-P one [18, 19]. It results in an indirect band gap in arsenene and antimonene nanosheets . For the corresponding arsenene and antimonene nanoribbons (AsNRs, SbNRs), their electronic and transport properties are still unknown so far. Do these AsNRs and SbNRs have different band features from the nanosheets? Can they have high hole mobilities akin to phosphorene? To address these questions, we preform a first-principle investigation on the electronic structures and carrier mobilities of arsenene and antimonene nanoribbons.
The first-principle calculations are performed by the VASP code within the Perdew-Burke-Ernzerhof (PBE) projector augmented wave pseudopotentials and plane-wave basis sets of 400 eV cutoff energy . A k-mesh of 1×5×1 / 1×7×1 is utilized in the relaxation for the armchair/zigzag nanoribbons, and the k-mesh grid is increased to 1×15×1 and 1×25×1 in the static and band calculations, respectively. A vacuum layer of more than 12.5 Åis used to simulate the isolated nanoribbons. The lattice constants along the periodic directions and all the internal coordinates are optimized until the convergence of the force on each atom is less than 0.01 eV/Å. The hybrid exchange and correlation functional of Heyd-Scuseria-Ernzerhof (HSE) has been used to check the obtained results. In the calculations, the HSE06 form with a screening parameter of 0.11 bohr−1 is used, and the HSE calculations are done by the FHI-aims code .
Results and Discussion
Firstly, to verify the accuracy of our calculations, we perform investigations on the arsenene and antimonene nanosheets. Our calculated results show that both arsenene and antimonene have the chair-buckled honeycombs, in which the buckling height between two sublattices are up to 1.40 and 1.64 Å, respectively. The buckled structures suggest that different from graphene, arsenene and antimonene prefer the sp3 hybridization. The in-plane lattice constants are 3.60 and 4.12 Åfor arsenene and antimonene. Indirect semiconducting behaviours are found in these nanosheets, for which the valence band maximum (VBM) is at the Γ point and the conduction band minimum (CBM) is along the Γ−M line. The calculated PBE band gaps are 1.59 and 1.28 eV for As and Sb nanosheets, respectively. All these structural and electronic properties of arsenene and antimonene agree well with previous studies [17–19].
Besides that, since the spacial distribution of VBM and CBM is limited by the ribbon width, quantum confinement effect is appreciable on the gaps of AsNRs and SbNRs. Figure 4c, f plots the gap variations of AsNRs and SbNRs versus the ribbon width. It shows that the gap sizes are gradually decreased with the increasing ribbon widths, and the varying trend can be fit as Δ G =Δ 0+γ/W . Here, Δ G is the band gap, Δ 0 is a fit parameter, which is expected to close to the 2D value of nanosheets, W is the ribbon width, and γ is a parameter representing the strength of quantum confinement. For AsNRs, we obtain the Δ 0= 1.44 (1.55) eV and γ= 8.67 (4.29) eV/Åfor armchair (zigzag) ones. Similarly, the aSbNRs (zSbNRs) have the Δ 0= 1.15 (1.22) eV and γ= 8.28 (4.23) eV/Å. These obtained γ values indicate that the quantum confinement is stronger in the armchair nanoribbons than in the zigzag ones for both arsenene and antimonene, which results in larger gaps in the armchair case. The Δ 0 of aAsNRs and aSbNRs deviate from their 2D value by about 0.14 and 0.13 eV, indicating the edge states still slightly affect the band gaps. While for the zAsNRs and zSbNRs, their Δ 0 converges to the 2D values within −0.03 and −0.05 eV, suggesting the weak effect of zigzag edges.
In summary, we investigate the electronic properties of arsenene and antimonene nanoribbons. It is found that for both arsenene and antimonene, the armchair nanoribbons are indirect semiconductors, while the zigzag nanoribbons are direct ones regardless of the ribbon width. The quantum confinement is stronger in the armchair nanoribbons than in the zigzag ones, causing bigger band gaps in the armchair case. Due to the special charge distributions of band edges, As and Sb nanoribbons have large deformation potential constants, which result in a conventional carrier mobility in the magnitude of 101–102 cm2/Vs. Similarly, owing to the same reason, the carrier mobilities of 2D arsenene and antimonene nanosheets are only 0.5–1.2 ×103 cm2/Vs, which are much lower than the phosphorene value. Due to the shape-dependent band features and large deformation potential constants, the arsenene- and antimonene-based nanomaterials will have potential applications in nanoelectronics and nanodevices.
The authors acknowledge the supports from the Zhejiang Provincial Natural Science Foundation of China (LY15A040008), National Natural Science Foundation of China (Grant No. 11474081, 11104052, 11104249), and Shanghai Supercomputer Center of China.
- Li L, Yu Y, Ye GJ, Ge Q, Ou X, Wu H, et al.Black phosphorus field-effect transistors. Nat Nanotech. 2014; 9:372–7.View ArticleGoogle Scholar
- Liu H, Neal AT, Zhu Z, Luo Z, Xu X, Tománek D, et al.Phosphorene: an unexplored 2d semiconductor with a high hole mobility. ACS Nano. 2014; 8:4033–041.View ArticleGoogle Scholar
- Ding Y, Wang Y, Shi L, Xu Z, Ni J. Anisotropic elastic behaviour and one-dimensional metal in phosphorene. Phys Status Solidi RRL. 2014; 8:939–42.View ArticleGoogle Scholar
- Manjanath A, Samanta A, Pandey T, Singh AK. Semiconductor to metal transition in bilayer phosphorene under normal compressive strain. Nanotechnology. 2015; 26:075701.Google Scholar
- Wang G, Pandey R, Karna SP. Phosphorene oxide: stability and electronic properties of a novel two-dimensional material. Nanoscale. 2015; 7:524–31.View ArticleGoogle Scholar
- Qiao J, Kong X, Hu ZX, Yang F, Ji W. High-mobility transport anisotropy and linear dichroism in few-layer black phosphorus. Nat Commun. 2014; 5:4475.Google Scholar
- Peng X, Wei Q. Chemical scissors cut phosphorene nanostructures. Mater Res Express. 2014; 1:045041.Google Scholar
- Guo H, Lu N, Dai J, Wu X, Zeng XC. Phosphorene nanoribbons, phosphorus nanotubes, and van der Waals multilayers. J Phys Chem C. 2014; 118:14051–14059.View ArticleGoogle Scholar
- Li W, Zhang G, Zhang YW. Electronic properties of edge-hydrogenated phosphorene nanoribbons: a first-principles study. J Phys Chem C. 2014; 118:22368–2372.View ArticleGoogle Scholar
- Peng X, Copple A, Wei Q. Edge effects on the electronic properties of phosphorene nanoribbons. J Appl Phys. 2014; 116:144301.Google Scholar
- Xu LC, Song XJ, Yang Z, Cao L, Liu RP, Li XY. Phosphorene nanoribbons: passivation effect on bandgap and effective mass. Appl Surf Sci. 2015; 324:640–4.View ArticleGoogle Scholar
- Qi J, Qian X, Qi L, Feng J, Shi D, Li J. Strain-engineering of band gaps in piezoelectric boron nitride nanoribbons. Nano Lett. 2012; 12:1224–1228.View ArticleGoogle Scholar
- Ramasubramaniam A, Muniz AR. Ab initio studies of thermodynamic and electronic properties of phosphorene nanoribbons. Phys Rev B. 2014; 90:085424.Google Scholar
- Tran V, Yang L. Scaling laws for the band gap and optical response of phosphorene nanoribbons. Phys Rev B. 2014; 89:245407.Google Scholar
- Carvalho A, Rodin AS, Neto AHC. Phosphorene nanoribbons. EPL. 2014; 108:47005.Google Scholar
- Zhang J, Liu HJ, Cheng L, Wei J, Liang JH, Fan DD, et al.Phosphorene nanoribbon as a promising candidate for thermoelectric applications. Sci Rep. 2014; 4:6452.Google Scholar
- Zhang S, Yan Z, Li Y, Chen Z, Zeng H. Atomically thin arsenene and antimonene: semimetal-semiconductor and indirect-direct band-gap transitions. Angew Chem Int Ed. 2015; 54:3112.Google Scholar
- Kamal C, Ezawa M. Arsenene: Two-dimensional buckled and puckered honeycomb arsenic systems. Phys Rev B. 2015; 91:085423.Google Scholar
- Zhu Z, Guan J, Tomanek D. Strain-induced metal-semiconductor transition in monolayers and bilayers of gray arsenic: a computational study. Phys Rev B. 2015; 91:161404.Google Scholar
- Wang Y, Ding Y. Unexpected buckled structures and tunable electronic properties in arsenic nanosheets: insights from first-principles calculations. J Phys: Condens Matter. 2015; 27:225304.Google Scholar
- Zhang Z, Xie J, Yang D, Wang Y, Si M, Xue D. Manifestation of unexpected semiconducting properties in few-layer orthorhombic arsenene. Appl Phys Express. 2015; 8:055201.Google Scholar
- Kresse G, Furthmuller J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys Rev B. 1996; 54:11169–86.View ArticleGoogle Scholar
- Blum V, Gehrke R, Hanke F, Havu P, Havu V, Ren X, et al.Ab initio molecular simulations with numeric atom-centered orbitals. Comput Phys Commun. 2009; 180:2175–196.View ArticleGoogle Scholar
- Zhu Z, Tománek D. Semiconducting layered blue phosphorus: a computational study. Phys Rev Lett. 2014; 112:176802.Google Scholar
- Ding Y, Wang Y. Electronic structures of silicene fluoride and hydride. Appl Phys Lett. 2012; 100:083102.Google Scholar
- Balendhran S, Walia S, Nili H, Sriram S, Bhaskaran M. Elemental analogues of graphene: silicene, germanene, stanene, and phosphorene. Small. 2015; 11:640–52.View ArticleGoogle Scholar
- Wagner P, Ivanovskaya VV, Melle-Franco M, Humbert B, Adjizian JJ, Briddon PR, et al.Stable hydrogenated graphene edge types: normal and reconstructed Klein edges. Phys Rev B. 2013; 88:094106.Google Scholar
- Xie J, Si MS, Yang DZ, Zhang ZY, Xue DS. A theoretical study of blue phosphorene nanoribbons based on first-principles calculations. J Appl Phys. 2014; 116:073704.Google Scholar
- Beleznay FB, Bogar F, Ladik J. Charge carrier mobility in quasi-one-dimensional systems: application to a guanine stack. J Chem Phys. 2003; 119:5690–695.View ArticleGoogle Scholar
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.