Some peculiarities of zirconium tungstate synthesis by thermal decomposition of hydrothermal precursors

摘要

This article discusses some peculiarities of the synthesis of ZrW2O8 (1) using thermal decomposition of the precursor ZrW2O7((OH)(1.5),CI0.5)center dot 2H(2)O (2) prepared by hydrothermal method. On hydrothermal synthesis of 2 the optimal concentration of hydrochloric acid in the reaction mixture is about 2.3 M. TG approach to determine the chemical composition of the precursor was suggested. It has been found that the precursor for the synthesis of zirconium tungstate has chemical formula 2. Thermal decomposition of the precursor 2 begins at 200 degrees C and affords an amorphous intermediate, which crystallizes as a cubic phase 1 above 550 degrees C with an exoeffect The temperature of the beginning of the transition from amorphous to the crystalline state is 350 +/- 25 degrees C. (C) 2014 Elsevier B.V. All rights reserved.