Stoerzinger, K.A.Risch, M.Suntivich, J.Lü, W.M.Zhou, J.Biegalski, M.D.Christen, H.M.AriandoVenkatesan, T.Yang, S.-H.ELECTRICAL & COMPUTER ENGINEERINGPHYSICS2014-10-072014-10-072013-06Stoerzinger, K.A., Risch, M., Suntivich, J., Lü, W.M., Zhou, J., Biegalski, M.D., Christen, H.M., Ariando, Venkatesan, T., Yang, S.-H. (2013-06). Oxygen electrocatalysis on (001)-oriented manganese perovskite films: Mn valency and charge transfer at the nanoscale. Energy and Environmental Science 6 (6) : 1582-1588. ScholarBank@NUS Repository. https://doi.org/10.1039/c3ee40321a17545692https://scholarbank.nus.edu.sg/handle/10635/82858We report that the oxygen reduction reaction (ORR) activities of (001)-oriented manganese perovskite films decrease from 10 to 1 nm by more than an order of magnitude, which can be attributed to the barrier associated with interfacial band bending that impedes electron transfer to the electrolyte, and reduction of Mn3+ due to charge transfer from the Nb:SrTiO 3 substrate. Furthermore, we show by substitution in La 1-x(Ca,Sr)xMnO3 that Mn3+, not Mn4+, is the active valence state for ORR. © 2013 The Royal Society of Chemistry.Article000317984700024