First Principles Study of Electronic and Optical Properties of Al-P Co-Doped ZnO in the Presence of Zn Vacancies.

The BP neural network optimized by the Adam algorithm was used to predict the defect formation energy of Al-P co-doped ZnO systems with different concentrations of P replacing O under the presence of different concentrations of V_Zn. It was found that the easily formed Al_ZnPo-1V_Zn, Al_ZnP_O-2V_Zn, and Al_Zn2P_O-1V_Zn systems. The first principles of density function were used to study the geometric, electronic, and optical properties of each system. The simulation results show that the bandgap values of the three systems have decreased relative to the intrinsic ZnO, among which Al_ZnP_O-1V_Zn and Al_ZnP_O-2V_Zn is still a p-type conductive system, Al_ZnP_O-2V_Zn has the highest conductivity. From the analysis of reflectivity, absorption rate, and light transmittance, Al_Zn2P_O-1V_Zn has the most relatively excellent optical properties, followed by AlznPo-2V_Zn.