Asymmetric Janus Functionalities Induced Changes in Structural, Electronic, Optical Characteristics of MXenes Ta4C3Tx

MXenes, novel discovered two-dimensional (2D) graphene analogues materials, have attracted continuous and tremendous attention in many application fields because of their excellent physiochemical properties and high performance in multifunctional applications. In present work, the changes of structural, electronic, and optical properties in the functional MXenes Ta4C3Tx are elucidated by using the first principles based on the density functional theory (DFT). It is confirmed that the functional layer (OH, F, O) has a significant effect on the optical properties of Ta4C3. Functional layers lead to the strong anisotropy in dielectric function, especially for asymmetry Janus Ta4C3-HOF. In the infrared region (photon energy <1.6 eV), the monolayer Ta4C3O2 has highest values of absorption coefficients and reflectivity. The transmitting mechanism of Ta4C3T2 are attributed to the thickness variation which affected by functional Janus atoms, further affect the sp2-hybridized of carbon. Symmetric O atoms passivated Ta4C3O2 has considered to be a better photothermal conversion material than pristine Ta4C3 in the infrared region.