Photocatalytic CO2 reduction promoted by uniform perovskite hydroxide CoSn(OH)6 nanocubes

Herein, we report the facile synthesis of uniform perovskite hydroxide CoSn(OH) 6 nanocubes and their first use as noble-metal-free, highly efficient and stable catalysts for the deoxygenative reduction of CO 2 to CO with visible light. The CoSn(OH) 6 sample is synthesized through a one-pot co-precipitation method and fully characterized by various techniques including XRD, FTIR, FESEM, TEM, EDX, EDX-mappings, XPS, DRS, and N 2 sorption measurements. The CoSn(OH) 6 solid is found by theoretical calculations to be capable of absorbing and activating CO 2 molecules on the (100) surface. Under the optimal reaction conditions, the CoSn(OH) 6 catalyst exhibits a high CO 2 reduction activity with visible light irradiation, affording a CO generation rate of 18.7   μmol   h −1 . The stability and reusability of the CoSn(OH) 6 catalyst for photocatalytic CO 2 reduction are solidly confirmed. Results of in situ photoluminescence spectroscopy and photocurrent response characterizations indicate that the CoSn(OH) 6 catalyst can efficiently promote the separation and transfers of photoexcited charge carriers during photocatalysis, and eventually leading to obviously enhanced CO 2 photoreduction performance. Moreover, a possible mechanism for the photocatalytic CO 2 reduction reaction is also proposed based on the results of activity evaluation and photo-/electro-chemical measurements.