Preparation and characterization of the spinel oxide ZnCo 2O 4 obtained by sol–gel method

Abstract

The zinc–cobalt-oxide spinel was obtained by the thermal decomposition of Zn–Co gel prepared by sol–gel method using oxalic acid as a chelating agent. The formation of spinel compound ZnCo 2O 4 has been confirmed by thermogravimetry (TGA) and X-ray powder diffraction (XRD) and Infra-red spectra (IR). It was shown that well-crystallized spinel structure is formed after calcination at 350 °C (low-temperature spinel). The particle size of 15∼20 nm has been measured by transmission electron microscope (TEM). Non-isothermal kinetic parameters ( E a, f( α) and A) for the decomposition process of the oxalate precursor were determined using differential scanning calorimetry (DSC) under air atmosphere. The sol–gel method provides a practicable and effective route for the synthesis the spinel compound ZnCo 2O 4 at low temperature.