Photocatalytic Approaches for Sustainable Olefin Transfer Hydrogenation and Semihydrogenation of Alkynes Using Natural Sunlight

A sustainable, solar energy-driven method for olefin hydrogenation and semihydrogenation of alkynes is presented. The approach uses a Pd nanoparticle-decorated semiconductor heterojunction photocatalyst that drives hydrogenation using renewable ethanol and sunlight for energy. The catalyst hydro-genates both terminal and internal double bonds, including activated and unactivated species, and preferentially hydrogenates alkynes over alkenes. This system represents a platform for transitioning critical catalytic processes toward sustainable approaches.