Thermal decomposition course of Eu(CH3COO)3·4H2O and the reactivity at the gas/solid interface thus established

The thermal decomposition course of europium acetate tetrahydrate (Eu(CH₃COO)₃·4H₂O) was probed on heating up to 1000 °C in a dynamic atmosphere of air by thermogravimetry and differential thermal analysis. The solid- and gas-phase decomposition products were identified by X-ray diffractometry, ex- and in situ infrared spectroscopy and mass spectrometry. Results obtained showed the acetate to dehydrate stepwise at 145-283 °C, and then decompose stepwise to yield eventually cubic-Eu₂O₃ at ≥663 °C encompassing the formation of intermediate oxycarbonate (Eu₂O(CO₃)₂/Eu₂O₂(CO₃) solid products (at 347-466 °C)) and H₂O, (CH₃)₂CO and CO₂ as primary gaseous products. A considerable enhancement of the production of the primary gas phase products at 400-450 °C and the emergence of (CH₃)₂CCH₂, CH₄ and CO molecules in the gas phase are ascribed to reactions occurring at the gas/solid interface at the expense of some of the primary products. These interfacial activities impart application-worthy adsorptive and catalytic functions for the associated solid products.