An in-depth in situ IR study of the thermal decomposition of copper trifluoroacetate hydrate

The pyrolysis of Cu(CF3COO)(2)center dot nH(2)O at temperatures up to 1000 degrees C, under flowing pure Ar, O-2 and O-2 saturated with water vapour, was extensively analysed. Decomposition reaction paths in all three media are proposed and various solid intermediates and gaseous products are identified. Cu-2(CF3COO)(3)(OH) and Cu(CF3COO)(2)center dot CuO formed sequentially, liberating TFAH at both stages. Cu(CF3COO)(2)center dot CuO decomposition occurred in a single endothermic step with an onset temperature of 263 degrees C in flowing dry Ar, but proceeded by a violent, exothermic and multistage route with onset temperatures of 216 and 209 degrees C in flowing dry O-2 and wet O-2 respectively, in all cases forming CuO. The formation of HF was also observed directly and the existence of a:CF2 radical inferred. The onset temperatures of the main decomposition are significantly lower than previously reported. This observation, and the violent exothermic nature of the decomposition in O-2 atmospheres, are suggested to have implications for sol-gel processing. (C) 2011 Elsevier B.V. All rights reserved.