Polyoxometalate-Based Single-Atom Photocatalyst for Hydrogen Production Coupled with Selective Furfurylamine Oxidation

Photocatalytic H₂ generation through water splitting faces inherent challenges, including the necessity for gas product separation and thermodynamic limitations of the oxygen evolution reaction. Herein, we propose a novel strategy to circumvent these obstacles by integrating the hydrogen evolution half-reaction with value-added furfurylamine oxidative transformation in a unified photocatalytic system. A polyoxometalate-supported single-atom photocatalyst demonstrates exceptional performance in synchronously driving both redox processes under photoexcitation. Systematic investigations reveal that photogenerated electrons efficiently reduce protons to generate H₂ (evolution rate: 494 umol·g^–1·h^–1), while the corresponding holes mediate selective oxidation of furfurylamine to N-furfurylidenefurfurylamine with 99% selectivity. Through advanced structural characterization (X-ray single crystal diffractometer) and density functional theory, we establish that the atomically dispersed metal centers coordinated with lacunary polyoxometalate frameworks create open active sites that significantly enhance interfacial charge transfer kinetics (improved by 3.7 times compared to nanoparticle counterparts). This synergistic configuration not only suppresses electron–hole recombination but also provides optimal adsorption configurations for organic substrates. To our knowledge, this work represents the first demonstration of constructing a closed redox cycle through coupled hydrogen production and biomass valorization using polyoxometalate-anchored single-atom photocatalysts.