Perovskite-like solid solution La0.5Ca0.5Mn0.5Co0.5O3 was tested during the total methane combustion reaction. During the reaction, there is a noticeable decrease in methane conversion, the rate of catalyst deactivation increasing with an increase in temperature. The in situ XRD and HRTEM methods show that the observed deactivation occurs as a result of the segregation of calcite and cobalt oxide particles on the perovskite surface. According to the TGA, the observed drop in catalytic activity is also associated with a large loss of oxygen from the perovskite structure.
Keywords: in situ XRD; microstructure; perovskite; phase transformation; recrystallization.