Co–In Bimetallic Hydroxide Nanosheet Arrays With Coexisting Hydroxyl and Metal Vacancies Anchored on Rod‐Like MOF Template for Enhanced Photocatalytic CO 2 Reduction

Abstract Layered double hydroxides (LDHs) can serves as catalysts for CO 2 photocatalytic reduction (CO 2 PR). However, the conventionally synthesized LDHs undergo undesired aggregation, which results in an insufficient number of active sites and limits the desirable electron transfer required for CO 2 PR. The metal‐organic framework (MOF) template‐grown LDHs demonstrate excellent promise for exploiting the strengths of both MOFs and LDHs. Herein, the in situ growth of MIL‐68(In)‐NH 2 MOF‐templated Co–In bimetallic catalyst (CoIn‐LDH/MOF) having an ultrathin nanosheet morphology on the preserved rod‐like MOF template is demonstrated. Compared to the conventionally grown bimetallic LDH (CoIn‐LDH), CoIn‐LDH/MOF not only exposes more active sites but also possesses hydroxyl vacancies ( V OH ) and Co vacancies ( V Co ). Thus, CoIn‐LDH/MOF performs a higher CO generation rate of 2320 µmol g −1 h −1 during CO 2 PR, demonstrating improved activity and selectivity than those in CoIn‐LDH. Experiments coupled with calculations reveal that the CoIn‐LDH/MOF‐driven CO 2 PR follows the * COOH pathway. The lower energy barriers for the formation of * COOH and CO(g) can be attributed to the coexistence of V OH and V Co in CoIn‐LDH/MOF, effectively promoting charge transfer and enhancing CO 2 PR performance. This study provides a new strategy to obtain high‐performant LDH‐based catalysts with improved morphology.