Formation of Zn- and Si-Based Oxide Systems: Analysis of Temperature Dependence of the Energy State

Abstract

This article presents the results of the thermal analysis of dried colloidal solutions based on zinc nitrate with changes in tetraethoxysilane (TEOS) content. The main stages of the thermal decomposition of the dried sols were established and the activation energies of each stage were determined based on the results of thermogravimetric measurements using the Erofeev-Kolmogorov approach. For each stage, the products of thermal destruction in the gas phase were determined by mass-spectrometry. It was shown that the chemical decomposition in all samples started at a temperature above 200°C, and the temperature of zinc hydroxonitrate decomposition increased with increasing TEOS content in the ash, while the activation energy of that process decreased. X-ray diffraction analysis revealed that the thermal decomposition of dried sols at 600°C resulted in the formation of mixtures of ZnO in hexagonal syngony with amorphous SiO2 in amounts from 10 to 50 wt%.