Effect of acceptor substitution in perovskites La1–x A x MnO3 ± δ (A = Ca, Sr, Ba) on the kinetics of interaction of gas-phase oxygen

The kinetics of interaction of gas-phase oxygen with oxygen of perovskite-like manganites La1 - xAxMnO3 ± δ (A = Ca, Sr, Ba) at a temperature of 850°C and an oxygen pressure of 1 kPa was studied by isotope exchange of oxygen with analysis of the gas phase. The rates of the interphase exchange, dissociative adsorption, and incorporation of oxygen in the crystal lattice of perovskites La0.7A0.3MnO3 ± δ (A = Ca, Sr, Ba) and La1–xSrxMnO3 ± δ (x = 0, 0.3, 0.4) were calculated. The dissociative adsorption of oxygen was found to be the limiting stage of the exchange. The influence of the defective structure of oxide La1 - xAxMnO3 ± δ on the mechanism of exchange with oxygen of the gas phase was discussed.