Influence of functional group and their number of atoms on structural, electronic and optical properties of Sc2C MXenes: A DFT study

Abstract

Two-dimensional (2D) materials MXenes have gained huge consideration due to their unique electronic, optical and mechanical properties for opto-electronics and other devices. In this work, structural, electronic and optical behavior of Sc2C MXenes by attaching different functional groups i.e. O, OH and F with different configurations (i.e varying number of atoms of functional group) is investigated using density functional theory (DFT). After determining the structural stability of all configurations further calculations are carried out. The calculations of band structures and density of states (DOS) show that the following configurations Sc2C, Sc2CO-G1, Sc2CO-G2, Sc2COH-G1, Sc2COH-G2, Sc2CF-G1, Sc2CF-G2, Sc2CF-G3 have metallic character and Sc2CO-G3, Sc2CO-G4, Sc2COH-G3, Sc2COH-G4, Sc2CF-G4 have band gap. It is observed that all the calculated properties are strongly dependent on both the functional group and their attached numbers. Furthermore, optical characteristics like absorption, dielectric function, refractive index, reflectivity, energy loss and conductivity are calculated and discussed. The calculated optical parameters revealed that the studied materials may be useful in anti-reflecting coatings.