Silica Zinc Titanate Wide Bandgap Semiconductor Nanocrystallites: Synthesis and Characterization

Abstract

SiO2x:ZnO: (1-x)TiO2 nanocrystallites were made via sol-gel route, and co-firing at a lower temperature (600oC). The synthesized nanocrystallites were characterized using several analytical techniques including XRD, SEM/TEM, FT IR, THz, and UV–visible spectroscopy analysis. The results appear that the silicate phase was used to promote the density of the nanocrystalline ceramic during calcination. The lower temperature calcined (∼600oC) nanocrystallites consist of ZnTiO3, Zn2SiO4, and TiO2 phases, with ZnTiO3 dominant rhombohedral phase, showing various electronic transitions. The obvious electronic properties give 2.8 eV as indirect bandgap transition and 3.35 ± 0.01 eV as direct bandgap transition with the increase of silica content. The dielectric constant is in the range 8 at a frequency higher than 104 Hz due to the formation of Zn2SiO4, and the ac conductivity is in the range 10− 10 to 10− 7 S/cm.