Interfacial Microenvironment Modulation Boosting Electron Transfer between Metal Nanoparticles and MOFs for Enhanced Photocatalysis.

Interfacial electron transfer between cocatalyst and photosensitizer is key in heterogeneous photocatalysis, yet the underlying mechanism remains subtle and unclear. Surfactant coated on the metal cocatalysts, greatly modulating the microenvironment of catalytic sites, is largely ignored. Herein, a series of Pt co-catalysts with modulated microenvironments, including polyvinylpyrrolidone (PVP) capped Pt nanoparticles (denoted as PtPVP ), Pt with partially removed PVP (PtrPVP ), and clean Pt without PVP (Pt), were encapsulated into a metal-organic framework (MOF), UiO-66-NH2 , to afford PtPVP @UiO-66-NH2 , PtrPVP @UiO-66-NH2 , and Pt@UiO-66-NH2 , respectively, for photocatalytic hydrogen production. The PVP appears to have a negative influence on the interfacial electron transfer between Pt and the MOF. Compared with PtPVP @UiO-66-NH2 , the removal of interfacial PVP improves the sluggish kinetics of electron transfer, boosting photocatalytic hydrogen production.