Computational study of systematic substitution of tungsten in two-dimensional Mo2C MXenes: Comparison of structural, electronic, optical, thermoelectric and mechanical properties

The technological applications of two-dimensional (2D) MXenes motivated us to investigate the systematic substation of tungsten in molybdenum carbide (Mo2C) MXenes using density functional theory (DFT). After confirming structural stability electronic behavior is analyzed which shows metallic behavior of all compositions. The analysis of optical parameters showed the maximum absorption in the ultraviolet region. Furthermore, the thermoelectric characteristics like Seebeck coefficient, electrical conductivity, thermal conductivity, specific heat capacity, power factor and ZT are calculated using semi-classical Boltzmann theory. These studied MXenes are found favorable thermoelectric MXenes. The mechanical characteristics such as Bulk Moduli, Shear moduli, Young Moduli, Poisson's ratio, compressibility, anisotropic ratio, lame's constant, ductility, brittleness, hardness, stiffness and nature of bonding are investigated and found that the pristine and all other W substituted Mo2C MXenes are mechanically stable except W2C MXenes. The obtained results revealed that these MXenes are favorable for thermoelectric and structural beams.