First-principles study on p-type transformation of ZnO doped by Ag element

The optical properties of intrinsic ZnO and Ag-doped ZnO for p-type transformation with different concentrations is studied using the first principles. The results show that the lattice constant and cell volume increase after Ag doping, and the total energy of the system gradually decreases, and the structure becomes more stable with the increase of Ag doping concentration. In supercell of Zn13Ag3O16, the impurity level is reduced, so the required ionization energy is reduced, which contributing to the ionization of impurity, leading to the significant improvement of charge transfer, hence, the conductivity is enhanced. Both absorption and reflection spectra appear red shift with the increase of Ag doping concentration, and the peak intensity is significantly increased with a higher Ag doping concentration. High Ag concentration is beneficial to the stability of p-type ZnO and the enhancement of photoelectric characteristics, which provides a basis for the application of ZnO in optoelectronic devices.