(766a) Advanced Materials Design for Visible-Light Driven Clean Chemical and Fuel Production

Solar energy harvesting and clean hydrogen generation by means of photoelectrochemical (PEC) water splitting is an emerging technology for sustainable energy research. However, the solar-to-hydrogen conversion efficiency of benchmarking materials still appear to be far from practice due to their limited light absorption of solar irradiation spectrum. One promising strategy for expanding the light absorption and improving the solar-to-hydrogen conversion efficiency is to combine photoelectrodes with plasmonic metals, which show expanded light absorption due to localized surface plasmon resonance (LSPR). However, so far, the majority of plasmonic photoelectrodes is still limited to noble metals which are not very stable and favorable for solution-based catalytic reactions. In this work, a non-metallic plasmonic effect was discovered from a rationally designed perovskite photoelectrode, namely SrTiO₃, with a periodically ordered nanoporous morphology and crystalline-core@amorphous-shell structure, due to the high density of free charge carriers introduced by oxygen vacancies in the amorphous shell. Such non-metallic plasmonic SrTiO₃ photoelectrode shows a dramatically plasmon-enhanced PEC water splitting performance under visible light, which is even comparable to the state-of-the-art plasmonic noble metal sensitized photoelectrodes. So far as we know, the formation and utilization of plasmonic perovskite photoelectrode for solar water splitting are rarely reported yet. This study will open a new paradigm for advanced catalyst design for PEC water splitting.