A slight deficiency of Ba in BaCoO3 boosts its performance as the cathode for proton-conducting solid oxide fuel cells (H–SOFCs). The Ba-deficiency compound Ba0.95CoO3 is successfully prepared, and the Ba-deficiency is found to be beneficial for the improvement in chemical stability. Theoretical calculations at the atomic level reveal that the Ba-deficiency in BaCoO3 improves the protonation of the material and also lowers the energy barriers in the proton migration procedure. Furthermore, surface catalytic activity towards O2 is enhanced with...
