Structure and photoluminescence of amorphous silicate composites containing ZnO particles synthesized from layered sodium silicate

This study has been conducted to synthesize ZnO/silicate composites from layered sodium silicate (δ-Na2Si2O5). For this purpose, various techniques have been employed to characterize the composites. X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR) indicate that ZnO/silicate composites are amorphous. Scanning electron microscope equipped with energy dispersive X-ray (SEM-EDX) was used to estimate the chemical compositions of the composites. Photoluminescence (PL) spectra of ZnO/silicate composites present a significant blue-shift of peak position and increasing intensity. The size of ZnO embedded in silicates was estimated to be 10–20 nm by transmission electron microscope (TEM). Thermogravimetric and differential thermal analyses (TG–DTA) suggest that the ZnO/silicate composites are different from the ZnO and layered sodium silicate. All these results confirmed that the amorphous ZnO/silicate composites formed and the photoluminescent property of ZnO embedded in the silicate was obviously improved in comparison with the uncovered ZnO.