CuTe₂Cl Monolayer: An Unexplored 2D Hybrid Structure with the Coexistence of Remarkable Charge Separation and Visible Light Absorption

Abstract

2D crystals with the coexistence of remarkable charge separation and visible light absorption are interesting for photovoltaic applications. Herein, a new 2D hybrid structure, namely, CuTe2Cl monolayer, with the coexistence of remarkable charge separation and visible light absorption, is determined. It is found that it is feasible to extract the CuTe2Cl monolayer from its bulk counterpart. The CuTe2Cl monolayer is viewed as a combination of the gyroidal CuCl and Te2 chains. The CuTe2Cl monolayer is dynamically and thermally stable. Interestingly, the charge distribution of the valence band maximum (VBM) locates mainly in the region of the CuCl chain, whereas the charge distribution of the conduction band minimum (CBM) locates mainly in the region of the Te2 chain, which implies a capability of remarkable charge separation in the CuTe2Cl monolayer. Moreover, it is also observed that the CuTe2Cl monolayer can exhibit strong absorption in the visible light region. Feasible obtainment, a stable structure, remarkable charge separation, and visible light absorption render the CuTe2Cl monolayer a promising 2D structure for photovoltaic applications.