Pt-Modified Nb2O5 for Efficient Photocatalytic Lactonization of Diols Coupled with H2 Evolution

Abstract

As vital chemical intermediates, lactones are widely utilized in pharmaceutical synthesis and other chemical industry sectors. However, the established synthetic routes for lactones are hampered by harsh reaction conditions and low yields. In this work, highly efficient light-induced lactonization of diols to lactones coupled with simultaneous H2 evolution is achieved over Pt/Nb2O5. Under light irradiation, the optimized Pt/Nb2O5 composite attains a phthalide production rate of 837.3 μmol g–1 h–1. Mechanistic studies demonstrate that the Pt nanoparticles (NPs) act as electron sinks to promote charge-carrier separation on Nb2O5 while accelerating proton reduction for H2 production. Meanwhile, photogenerated holes on Nb2O5 initiate the oxidation of adsorbed 1,2-benzenedimethanol (1,2-BM) to generate 2-formylbenzyloxy radicals (•O2H7C8), which subsequently undergo C–O coupling to form phthalide. This work provides valuable insights for the rational engineering of metal-decorated semiconductor photocatalysts for sustainable and high-efficiency lactone formation from diols with concomitant H2 generation.