Co‐Dissolved Isostructural Polyoxovanadates to Construct Single‐Atom‐Site Catalysts for Efficient CO2 Photoreduction

We explored a co-dissolved strategy to embed mono-dispersed Pt center into V2O5 support via dissolving [PtV9O28]7- into [V10O28]6- aqueous solution. The uniform dispersion of [PtV9O28]7- in [V10O28]6- solution allows [PtV9O28]7- to be surrounded by [V10O28]6- clusters via a freeze-drying process. The V centers in both [PtV9O28]7- and [V10O28]6- were converted into V2O5 via a calcination process to stabilize Pt center. These double separations can effectively prevent the Pt center agglomeration during the high-temperature conversion process, and achieve 100% utilization of Pt in [PtV9O28]7-. The resulting Pt-V2O5 single-atom-site catalysts exhibit a CH4 yield of 247.6 μmol g-1 h-1, 25 times higher than that of Pt nanoparticle on the V2O5 support, which was accompanied by the lactic acid photooxidation to form pyruvic acid. Systematical investigations on this unambiguous structure demonstrate an important role of Pt-O atomic pair synergy for highly efficient CO2 photoreduction.