Tailoring the structural and optical properties of zinc oxide with addition of bismuth oxide prepared by two step process

This study was done to investigate the impact of bismuth oxide (Bi2O3) composites on the zinc oxide (ZnO) properties for varistor applications. ZnO-Bi2O3 samples were prepared using a two-step process, precipitation, and solid-state method. Bi2O3 was added into ZnO at various concentrations (0, 0.5, 1.0 and 1.5 mol%). All samples were characterized using X-ray diffraction (XRD), Scanning electron microscope (SEM) and UV visible spectroscopy. XRD results have shown that the crystallite size of ZnO-Bi2O3 samples became smaller when Bi2O3 was added from 0.5 mol% to 1.0 mol%. However, the crystallite size of ZnO-Bi2O3 increased over 1.0 mol% of Bi2O3 concentration. The smallest particle and grain size of ZnO-Bi2O3 appeared when composite at 1.0 mol% concentration of Bi2O3. The homogeneity and smallest grain size might be suitable to be used for varistor application. The absorbance of ZnO-Bi2O3 decreased as the Bi2O3 concentration increased. Therefore, adding Bi2O3 at various concentrations into the ZnO host material can tailor its structural and optical properties.