Novel bonding patterns and optoelectronic properties of the two-dimensional SixCymonolayers

• DOI: 10.1039/c6tc05415c
• Publication Date: 2017-02-27T17:53:31Z
• Authors: Dong Fan; Shaohua Lu; Yundong Guo; Xiaojun Hu
• Keywords: Tetragonal crystal system

The search of new two-dimensional (2D) materials with novel optical and electronic properties is always desirable for material development. Here, we report a comprehensive theoretical prediction 2D SiC compounds different stoichiometries from C-rich to Si-rich. Besides the previously known hexagonal sheet, identified two types hitherto-unknown structural motifs distinctive bonding features. first type monolayer, including t-SiC t-Si$_2$C can be described by tetragonal lattice. Among them,t-SiC monolayer sheet featured each carbon atom binds four neighboring silicon atoms in almost same plane, constituting quasi-planar four-coordinated rectangular moiety. More interestingly, our calculations demonstrate that this structure exhibits strain-dependent insulator-semimetal transition, suggesting promising applications optoelectronic sensors. second silagraphyne acetylenic linkages(-C$\equiv$C-). Silagraphyne shows both high pore sizes Poisson's ratio. These make them potentially important separation membranes catalysis. Moreover, one proposed structures, $\gamma$-silagraphyne, direct-band-gap semiconductor bandgap 0.89 eV, which has strong absorption peak visible-light region, giving application ultra-thin transistors, sensor devices solar cell devices.