Hybrid Carbon Dioxide Reduction Photocatalysts Consisting of Macrocyclic Cobalt(III) Complexes Deposited on Semiconductor Surfaces

Abstract

Abstract Hybrid photocatalysts can be prepared by coupling metal‐ligand complexes with light‐harvesting semiconductors. It is often challenging and time consuming to derivatize ligands with anchoring groups to effectively attach onto surfaces. In this study, we synthesized hybrid carbon dioxide reduction photocatalysts by directly depositing two macrocyclic Co(III) complexes on three different semiconductor surfaces (TiO 2 , N−Ta 2 O 5 and C 3 N 4 ). The resulting hybrid photocatalysts were characterized with various techniques and tested in CO 2 reduction reactions under different light conditions. Excellent visible‐light CO 2 ‐reduction activity was obtained using C 3 N 4 as the light‐harvesting semiconductor. Density functional theory calculations were conducted to help understand interactions between the cobalt complexes with a model TiO 2 surface.