Light‐Assisted CO ₂ Hydrogenation over Pd ₃ Cu@UiO‐66 Promoted by Active Sites in Close Proximity

CO2 hydrogenation to methanol has attracted great interest while suffering from low conversion and high energy input. Herein, tiny Pd3 Cu nanoparticles are confined into a metal-organic framework (MOF), UiO-66, to afford Pd3 Cu@UiO-66 for CO2 hydrogenation. Remarkably, it achieves a methanol production rate of 340 μmol g-1 h-1 at 200 °C and 1.25 MPa under light irradiation, far surpassing that in the dark. The photo-generated electron transfer from the MOF to antibonding orbitals of CO2 * promotes CO2 activation and HCOO* formation. In addition, the Pd3 Cu microenvironment plays a critical role in CO2 hydrogenation. In contrast to the MOF-supported Pd3 Cu (Pd3 Cu/UiO-66), the Pd3 Cu@UiO-66 exhibits a much higher methanol production rate due to the close proximity between CO2 and H2 activation sites, which greatly facilitates their interaction and conversion. This work provides a new avenue to the integration of solar and thermal energy for efficient CO2 hydrogenation under moderate conditions.