Computational discovery and characterization of polymorphic two-dimensional IV-V materials
Computational discovery and characterization of polymorphic two-dimensional IV-V materials
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DOI：
10.1063/1.4967433
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发表时间：
2016-11-07
影响因子：
4
通讯作者：
Hennig, Richard G.
中科院分区：
文献类型：
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作者：
Ashton, Michael;Sinnott, Susan B.;Hennig, Richard G.
第一性原理计算预测了两种不同晶体结构的二维（2D）IV-V族MX化合物（M = Si，Ge，Sn，Pb; X = P，As，Sb，Bi）的稳定性和性质：由SiP，SiAs，GeP和GeAs的层状体结构启发的低对称性Cm层，以及先前预测的2D SiP的高对称性P（6）棒m2结构。计算结果表明，当X = As，Sb，Bi时，Cm结构更稳定，而当X = P时，P（6）过棒m2结构更稳定。具体地，对于大多数化合物，Cm带隙系统地大约15%，并且带偏移指示Cm晶体结构中的所有这些化合物将形成与它们的P（6）在棒m2多晶型物上接触的II型异质结。Pourbaix图预测，当暴露于水时，一些2D IV-V化合物是稳定的。出版社：AIP Publishing
First-principles calculations predict the stability and properties of two-dimensional (2D) group IV-V MX compounds (M = Si, Ge, Sn, Pb; X = P, As, Sb, Bi) in two distinct crystallographic configurations: a low symmetry Cm layer inspired by the layered bulk structures of SiP, SiAs, GeP, and GeAs, and a high symmetry P (6) over bar m2 structure previously predicted for 2D SiP. The calculations predict that the Cm structure is more stable for X = As, Sb, and Bi, and the P (6) over bar m2 structure for X = P. The electronic properties of the two structures are quite different. Specifically, the Cm band gaps are systematically larger by about 15% for most compounds, and the band offsets indicate that all of these compounds in the Cm crystal structure will form type II heterojunctions in contact with their P (6) over bar m2 polymorphs. Pourbaix diagrams predict that a few of the 2D IV-V compounds are stable when exposed to water. Published by AIP Publishing.