Ultrafast Hole Preservation with Undercoordinated Tungsten for Efficient Solar-to-Chemical Conversion

Abstract

Solar-to-chemical conversion is crucial, as it can form chemicals that are easy to store. Hydrogen peroxide (H₂O₂) represents a favorable chemical for energy storage and disinfection. Solar driven H₂O₂ photocatalysis is a promising method, as it could greatly reduce costs and provide on-demand production. The big challenge lies in achieving optimum production rate with reasonable materials cost. Herein, by precise control of synthetic conditions, tungsten (W)-based metal–organic-framework (MOF) with up to 28.64% undercoordinated W^4/5+ is prepared. The H₂O₂ photoproduction rate up to 330,000 μmol g^–1 h^–1 L^–1 is achieved, highest for non-noble metal-based catalysts. A multistage solar driven evaporation system further increases H₂O₂ concentration to 0.43 wt %, reaching application level for water treatment. Such an efficient production originates from ultrafast hole preservation, which enables a two-electron transfer reaction pathway for H₂O₂ production. Our work highlighted the potential of MOF-based photocatalyst for on-demand and large scale H₂O₂ production.