Properties of Mo-based TMDCs/Ti2CT2（T = O, F, OH）vdWs heterostructures for full spectrum electromagnetic absorption

Abstract

The structure, electronic and optical properties of transition metal dichalcogenides (TMDCs = MoS2, MoSe2, MoSSe), Ti2CT2 (T = O, F, OH) MXenes monolayers and their corresponding TMDCs/Ti2CT2 vdWs heterostructures are comprehensively studied by density functional theory. It is revealed that the terminal group T has a crucial influence on the electronic properties of TMDCs/Ti2CT2, and the spin-orbit coupling (SOC) originating from the d-orbital of Mo atoms in MoSSe leads to large Rashba band splitting. And the TMDCs/Ti2CO2 are type II vdWs heterojunctions, retaining the band dispersion of the TMDCs or Ti2CT2 original monolayers. There is a notably electrostatic potential difference between the original monolayers, and the vdWs heterostructures based on Ti2CF2 and Ti2C(OH)2 exhibit mostly Ohmic contact. TMDCs/Ti2CT2 have excellent absorption capacity in the energy range larger than 5 eV, and inherits the wide absorption range of Ti2CT2 monolayer and the small energy loss of TMDCs in the energy range smaller than 5 eV, which makes them into full spectrum electromagnetic absorbing materials.