Single-atom copper modified hexagonal tungsten oxide for efficient photocatalytic CO2 reduction to acetic acid

Selective production of C 2+ chemicals from photocatalytic CO 2 reduction remains a big challenge due to the inert CO 2 molecular and vague C C coupling process. Herein, contributed by its uniform hexagonal pores, two-dimensional h'-H x WO 3 is selected as the support to realize single atom Cu loading (Cu/WO 3 ). Under the irradiation of light, the h'-H x WO 3 transformed into electron- and proton-rich tungsten bronze, which ensured the supply and transfer of multiple electrons/protons for the CO 2 reduction. Meanwhile, the similar coordination environment and appropriate distance of the Cu active sites presented by the Cu/WO 3 not only enable the adsorption and activation of CO 2 but also enhance the efficient C C coupling. Thus, Cu/WO 3 photocatalyst achieves the conversion of CO 2 to CH 3 COOH with a selectivity of 67 %, which is about 17 times higher than that of pristine h'-H x WO 3 . This work expands the route to prepare highly active single-atom catalysts, benefiting CO 2 photoreduction to selective reduction products.