Production of H2O2 via Energy Transfer Photocatalysis by Coupling with Furfuryl Alcohol Conversion over an Amide-Functionalized Heptazine Framework

Photocatalytic oxygen reduction provides a sustainable approach for hydrogen peroxide (H2O2) synthesis, but the charge carrier-based pathway is severely limited by inefficient charge separation and redox decomposition of the produced H2O2. Energy transfer photocatalysis (EnTP) is an alternative charge-carrier-free route for H2O2 synthesis. Herein, we propose a strategy of killing two birds with one stone to simultaneously realize the synthesis of H2O2 and conversion of a biomass derivative by coupling EnTP with the Achmatowicz reaction. Results show efficient production of H2O2 at a rate of 14.6 mmol gcat-1 h−1 and an apparent quantum yield of 44.1% at 420 nm, coupled with the conversion of biomass-derived furfuryl alcohol (FFA) to hydroxy-2H-pyran-3(6H)-one with a high selectivity of 85.9%. Such a performance was attributed to the efficient EnTP over the amide-functionalized heptazine framework photocatalyst for singlet oxygen generation, which induces the FFA conversion and concurrently produces H2O2. A systematic study of the photoexcitation process of the catalysts reveals that the amide-functionalization significantly improves the intersystem crossing efficiency, as the structural modification optimizes the electronic structure and thus tunes the composition and distribution of energy bands.