Theoretical investigations of asymmetric functionalized Y2C-based MXene monolayers

Abstract

In this research work, the structural, electronic, optical characteristics, and the work function of the asymmetric functionalized Y2CTT’ (T, T’ = F, Cl, Br) MXene monolayers have been investigated using the density functional approach. Herein, bare Y2C MXene monolayer is metallic which is functionalized with two different halide atoms. The upper surface of Y2C monolayer is terminated with T halide atom and the lower surface is terminated with T′ halide atom. For the computation of electronic band structure, generalized gradient approximation with PBE functional as well as hybrid functional (HSE06) is employed, which ensures that the Y2CClBr, Y2CFBr and Y2CFCl monolayers are semiconductor with the indirect bandgap of 1.66 eV, 1.81 eV and 1.82 eV. The evaluation of optical properties using the random phase approximation suggests that the Y2CTT’ monolayers start absorption in IR region, exhibits a small absorption in the visible part and a significant absorption in ultraviolet part of the electromagnetic spectrum. Hence, Y2CTT’ monolayers are the promising candidates in photonic devices specifically ultraviolet detectors, ultraviolet radiation absorbers, etc.