Zhang Wei, Chai Changchun, Fan Qingyang, Song Yanxing, Yang Yintang
School of Microelectronics, Xidian University, Xi'an, 710071, China.
College of Information and Control Engineering, Xi'an University of Architecture and Technology, Xi'an, 710071, China.
Chemphyschem. 2021 Jun 4;22(11):1124-1133. doi: 10.1002/cphc.202100055. Epub 2021 May 11.
Based on first-principles calculations, a novel family of two-dimensional (2D) IV-V compounds, XC (X=N, P, As and Sb), is proposed. These compounds exhibit excellent stability, as determined from the cohesive energies, phonon dispersion analysis, ab initio molecular dynamics (AIMD) simulations, and mechanical properties. In this type of structure, the carbon atom is sp hybridized, whereas the X (N, P, As and Sb) atom is nonplanar sp hybridized with one 2p orbital filled with lone pair electrons. NC , PC , AsC and SbC monolayers are intrinsic indirect semiconductors with wide bandgaps of 2.02, 2.36, 2.77, and 2.85 eV (based on HSE06 calculations), respectively. After applying mechanical strain, PC , AsC and SbC monolayers can be transformed from indirect to direct semiconductors. The appropriate bandgaps and well-located band edge positions make XC monolayers potential materials for photocatalytic water splitting. XC family members also have high absorption coefficients (∼10 cm ) in the ultraviolet region and higher electron mobilities (∼10 cm V s ) than many known 2D semiconductors.
基于第一性原理计算，提出了一类新型的二维（2D）IV-V化合物XC（X = N、P、As和Sb）。通过结合能、声子色散分析、从头算分子动力学（AIMD）模拟和力学性能确定，这些化合物表现出优异的稳定性。在这种结构类型中，碳原子是sp杂化的，而X（N、P、As和Sb）原子是非平面sp杂化的，有一个2p轨道填充着孤对电子。NC、PC、AsC和SbC单层是本征间接半导体，其带隙分别为2.02、2.36、2.77和2.85 eV（基于HSE06计算）。施加机械应变后，PC、AsC和SbC单层可以从间接半导体转变为直接半导体。合适的带隙和良好定位的带边位置使XC单层成为光催化水分解的潜在材料。XC家族成员在紫外区域也具有高吸收系数（10⁵ cm⁻¹），并且比许多已知的二维半导体具有更高的电子迁移率（10³ cm² V⁻¹ s⁻¹）。
