Water electrolysis on La1−xSrxCoO3−δ perovskite electrocatalysts

作者：J. Tyler Mefford, Rong Xi, Artem M. Abakumov, William G. Hardin, Sheng Dai, Alexie M. Kolpak, Keith P. Johnston, Keith J. Stevenson · 发表于：Nature Communications · 年份：2016 · DOI：10.1038/ncomms11053 · 被引用次数：1178 · 研究领域：Electrocatalysts for Energy Conversion、Advanced battery technologies research、Advancements in Solid Oxide Fuel Cells

Perovskite oxides are attractive candidates as catalysts for the electrolysis of water in alkaline energy storage and conversion systems. However, the rational design of active catalysts has been hampered by the lack of understanding of the mechanism of water electrolysis on perovskite surfaces. Key parameters that have been overlooked include the role of oxygen vacancies, B-O bond covalency, and redox activity of lattice oxygen species. Here we present a series of cobaltite perovskites where the covalency of the Co-O bond and the concentration of oxygen vacancies are controlled through Sr(2+) substitution into La(1-x)Sr(x)CoO(3-δ) . We attempt to rationalize the high activities of La(1-x)Sr(x)CoO(3-δ) through the electronic structure and participation of lattice oxygen in the mechanism of water electrolysis as revealed through ab initio modelling. Using this approach, we report a material, SrCoO2.7, with a high, room temperature-specific activity and mass activity towards alkaline water electrolysis.