Theoretical study on SmxSr1−xMnO3 as a potential solid oxide fuel cell cathode

• SSM50 has better oxygen storage capacity than LSM50.
• The absorbed O2 species on SSM50 (100) surface are readily dissociated.
• SSM50 has the best catalysis for the ORR among the considered systems.

Cubic perovskite SmxSr1−xMnO3 (SSM) surface and bulk models have been constructed to simulate the oxygen reduction reactions by employing first-principles calculations. The results demonstrate that oxygen vacancies can be formed easily in Sm0.5Sr0.5MnO3 (SSM50). The oxygen migration barrier in bulk SSM50, which is predicted by the nudged elastic band (NEB) method, is the lowest, while the adsorption energy of O2 molecular on SSM50 (100) surface is the lowest among the considered doping systems, indicating the potential application of SSM50 as a cathode for intermediate-temperature solid oxide fuel cell (IT-SOFC). The reaction mechanisms of oxygen reduction on SSM50 (100) surface have also been studied.