Exploration of Structures of Two-Dimensional Boron-Silicon Compounds with sp(2) Silicon.
The most stable structures of two-dimensional (2D) boron-silicon (B-Si) compounds containing planar sp(2)-bonding silicon (sp(2)-Si) are explored using the first-principles calculation-based particle-swarm optimization method. Among 10 B-Si compounds considered, we find that for BSi4, BSi3, BSi, B2Si, B3Si, B5Si, and B6Si, each Si atom is bonded with three B or Si atoms within the same plane, representing a preference of planar sp(2)-Si structure in B-Si compounds. For BSi2 and B4Si, the predicted lowest-energy structures entail a small out-of-plane buckling. Furthermore, a planar-tetracoordinated Si (ptSi) atom bonded with four B atoms within the same plane is observed in the lowest-energy structure of B7Si compound. Dynamical stabilities of the predicted 10 2D B-Si compounds are confirmed via phonon-spectrum calculation. The lowest-energy 2D B-Si compounds are all metals, regardless of the B-Si stoichiometry considered in this study.
†Department of Chemistry and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States.
Jun
J
Dai
†Department of Chemistry and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States.
Yu
Y
Zhao
‡CAS Key Lab of Materials for Energy Conversion, Department of Materials Science and Engineering and Hefei National Lab for Physical Science at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
Xiaojun
X
Wu
§Department of Chemical Physics and Hefei National Lab for Physical Science at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
Jinlong
J
Yang
†Department of Chemistry and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States.|§Department of Chemical Physics and Hefei National Lab for Physical Science at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
Xiao Cheng
XC
Zeng
density functional theory; electronic properties; phonon spectra; sp2-bonding silicon; structure search