An intense ultraviolet photoluminescence in sol gel ZnO SiO₂nanocomposites

Abstract

We report the phenomenon that the intensity of the ultraviolet (UV) photoluminescence (PL) from ZnO was greatly enhanced by incorporating ZnO into the SiO2 matrix. PL excitation results show that both the ZnO nanoparticles and the SiO2 matrix in the nanocomposites contribute to the luminescence process for the UV band. On the basis of the x-ray photoelectron spectra, we suggest that interface energy states are formed due to the presence of Zn–O–Si bonds between ZnO nanoparticles and the SiO2 matrix. A tentative model concerning the contribution of the ZnO nanoparticles, SiO2 matrix, and ZnO–SiO2 interface is suggested to explain the PL enhancement effect.