Effect of heating rate on structural and optical properties of Si and Mg co-doped $$\hbox {ZrO}_{2}$$ ZrO 2 nanopowders

Abstract

Nanopowders of \(\hbox {ZrO}_{2}\) doped with Si and Mg were prepared by process controlled sol–gel method. The effects of doping and heating rate (1, 4, 7, 10 \(^{\circ }\hbox {C}\)/min and calcination temperature of 800 \(^{\circ }\hbox {C}\)) on phase formation and optical properties of zirconia nanopowders were studied by X-ray diffraction (XRD), transmission electron microscopy, and UV–Vis absorption spectroscopy. XRD results showed that different heating rates have a great effect on the tetragonal and cubic phase formation, crystallinity, and particle size of doped \(\hbox {ZrO}_{2}\). Depending on the heating rate, band gap energy of \(\hbox {Si}^{4+}\) and \(\hbox {Mg}^{+2}\) doped \(\hbox {ZrO}_{2}\) crystals decreased. The minimum band gap was estimated to be \(\sim \)3–3.2 eV from UV–Vis spectra.