A natural molecule-driven organometallic conformal overlayer for high efficiency photoelectrochemical water splitting

A surface manipulation of metal oxide-based photoelectrodes with overlaid co-catalysts has emerged as a promising strategy for boosting photoelectrochemical (PEC) water splitting activities. We demonstrate a nature molecule-mediated novel organometallic overlayer with exposed single atoms (SAs) on the surface of nanoparticulate tungsten oxide (WO3) photoanode with a significantly boosted solar water splitting activity and its long-term durability in aqueous electrolytes with wide pH range via a spontaneous one-pot assembly of a quercetin-nickel (QNi) complex on WO3. The QNi complex with exposed Ni SAs modified WO3 photoanode achieves a more that 2.7-fold enhancement on photocurrent density at 1.23 VRHE in a mild condition (pH 7) and remarkable long-term durability of over 15 h. This work provides an attractive idea for efficient water splitting by utilizing a facile spontaneous assembly of organometallic overlayer with environmentally friendly materials, which is a step towards the goal of achieving green hydrogen. [Display omitted] •Assemble a nature molecule-mediated quercetin-Ni (QNi) overlayer on WO3.•QNi/WO3 shows high stability for PEC water splitting in wide pH range.•The exposed Ni single atoms highly improve the surface catalytic kinetics.•This quercetin-Ni complex provides an strategy for the concept of green hydrogen.