Electronic structure and optical properties of Cu3PX4(X=S and Se): Solar cell made of abundant materials

The electronic structure and optical properties of Cu3PX4 (X=S and Se) have been investigated employing the full potential linearized augmented plane wave (FP-LAPW) method. The modified Becke-Johnson exchange potential (TB-mBJ) was used along with the generalized gradient approximation proposed by of Perdew-Burke-Ernzerhof (GGA-PBE) to treat the exchange-correlation contribution. Our results are found to be exceptionally in good agreement with exciting theoretical and experimental data. The calculated band structure shows a direct band gap of 1.376 eV for Cu3PSe4 and an indirect band gap of 1.87 eV for Cu3PSe4. The band gap dependent on optical properties such as dielectric function and absorption coefficient are predicted within this study. The optical responses suggest that Cu3PSe4 is promising as a photovoltaic material thanks to its high absorption coefficient and photoconductivity in the visible light.