Photocatalytic CO2 Conversion of M0.33WO3 Directly from the Air with High Selectivity: Insight into Full Spectrum-Induced Reaction Mechanism

Natural photosynthesis is a solar light-driven process utilized by plants to convert CO2 and water into carbohydrate molecules. The goal of artificial photosynthesis is the reduction of CO2 directly from air into high purity value-added products at atmospheric pressure. However, its realization, combined with deep mechanism investigation, is a huge challenge. Herein, we demonstrate that hexagonal tungsten bronze M0.33WO3 (M = K, Rb, Cs) series with {010} facets, prepared by a peculiar “water-controllable releasing” solvothermal method, showed excellent full spectrum (UV, visible, and NIR lights)-induced photocatalytic CO2 reduction performance directly from the air at ambient pressure. Particularly, after 4 h near-infrared light irradiation, ca. 4.32% CO2 in the air could be converted into CH3OH with 98.35% selectivity for Rb0.33WO3. The experiments and theoretical calculations unveiled that the introduced alkali metal atom occupied the tunnel of hexagonal structure and donated more free electrons to reco...