Hierarchically structured semiconductor@noble-metal@MOF for high-performance selective photocatalytic CO2 reduction

Abstract

Photocatalytic CO2 reduction to convert solar energy to clean energy remains a critical challenge in exploring efficient catalysts. Herein, a hierarchical structured BiVO4@Au@UiO-66-NH2 with high photocatalytic activity was fabricated. The theoretical calculations revealed that the metal–organic framework (MOF) with relative higher conduction band (CB) and UiO-66-NH2 with relative lower valence band (VB) could absorb full light spectrum, combining Au nanoparticle with suitable Fermi level into a particulate tandem heterojunction. This configuration can not only lower the activation barrier of CO2 reduction using the rich active site of MOF, but also improve the selectivity toward CO by optimizing the reaction pathway. Notably, the experimental evaluation proved that BiVO4@Au@UiO-66-NH2 displays a producing rate of 232.7 μmol h−1 g−1 for CO and a selectivity of 97.2%. The investigation reveals that elaborately integrating multiple functional components into such a hierarchical structure enables optimizing crucial processes in photocatalytic CO2 conversion and enhancing selectivity via synergistic catalysis.

Keywords

• Photocatalysis
• Metal–organic framework (MOF)
• Heterojunction
• High selectivity