Enhanced photoelectrocatalytic hydrogen evolution using off-stoichiometry La0.43FeOy films

In this work, the influence of stoichiometry LaxFeOy films on their activity for H2 production by photoelectrochemical (PEC) water splitting was investigated. Thin were deposited electrodes magnetron co-sputtering and composition controlled adjusting power applied metallic iron lanthanum targets. The highest photoactivity observed La0.43FeOy films. crystallization these photocatalytic further improved oxidation in an external furnace at 650 °C 2 h. Transmission electron microscopy (TEM) analyses confirm formation LaFeO3 crystallites film show a thin continuous polycrystalline Fe2O3 layer surface. presence upper surface originates from exsolution mechanism typically non-stoichiometric perovskites. improvement properties stoichiometry, temperature thickness confirmed measurements performed mass spectrometry. We observe large increase rate (103%) comparison with stoichiometric film. catalytic performances composed earth abundant, low-cost non-toxic elements, make them high interest materials photoelectrodes PEC systems.