A 2D T-carbon 2-(111) structure with tunable electric and optical properties via chemical decorations: a first-principles investigation

We proposed a new two-dimensional carbon material named 2-(111) planar T-carbon, which is obtained by slicing bulk T-carbon along its (111) crystallographic direction. 2-(111) planar T-carbon's optical and electrical properties can be engineered via surface decoration. Comparing the DFT phonon spectra of pristine and five decorated 2-(111) planar T-carbon obtained by first-principles calculations, we conclude that surface decoration presents a promising, effective, and feasible strategy to improve the structural stability of 2-(111) planar T-carbon. The calculated band structures and electronic properties show direct electronic band gap values between 0.17 eV (-O= decorated) and 2.21 eV (Hydrogenated). Chemical decoration also promises blue or red energy shifts in its optical properties.