Radical and oxidative pathways in the pyrolysis of a barium propionate-acetate salt

Abstract

Film and powder samples from a BaAc2 solution in propionic acid/MeOH were decomposed in different atmospheres and their thermal decomposition was characterized by means of thermogravimetry coupled with evolved gas analysis techniques (TG-FTIR, EGA-MS) and chemical and structural methods (EA, XRD, FTIR). The thermal behavior of the films was found to be different than the corresponding powder, in terms of volatiles, kinetics, intermediate phases and purity of final product. The mixed Ba-Prop-Ac salt obtained from solution decomposes to BaCO3 before 400 °C through oxidative degradation, and above 400 °C in inert atmosphere through a radical path releasing symmetrical ketones. Its double melting behavior is also highlighted and its decomposition understood by comparison with BaProp2 and BaAc2 precursors, and put into the context of YBa2Cu3O7-∂ (YBCO) film pyrolysis