The thermal decomposition of palladium acetate

TLDR: In this article, the nature, products, and enthalpy of the thermal decomposition of [Pd(CH3CO2)2]3 were determined in air, nitrogen and vacuum.

Abstract: The nature, products, and enthalpy of the thermal decomposition of [Pd(CH3CO2)2]3 were determined in air, nitrogen and vacuum. Thermogravimetry, differential thermal analysis, evolved gas analysis, differential scanning calorimetry, and infrared spectroscopy were used to characterize the process and products. In vacuum the trimer volatilizes completely below 200 °C. The IR spectrum of the gas phase species is reported. At atmospheric pressure the material decomposed to Pd between 200 and 300 °C depending upon the rate of heating. The apparent activation energy for this process is about 115 ± 5 kJ mol−1 and the enthalpy is 440 ± 20 kJ mol−1. In the presence of oxygen, however, oxidation of the ligands leads to an overall exothermic process. The resulting the Pd then slowly oxidizes to PdO2 up to the decomposition temperature of the oxide near 800 °C. There is the slight loss of a Pd containing species, presumably due to sublimation or gas entrainment, during the decomposition below 300 °C. The extent of this loss increases with increasing heating rate, approaching 10% of the total Pd at heating rates of 64 °C min−1.