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

• Published in: Applied catalysis. B, Environmental Environmental, 2018-05, Vol.224, p.1009-1016
• Main Authors: Lin, Xiahui, Gao, Yilin, Jiang, Min, Zhang, Yongfan, Hou, Yidong, Dai, Wenxin, Wang, Sibo, Ding, Zhengxin
• Format: Article
• Language: English
• Subjects: CO2 reduction; CoSn(OH)6; Nanocubes; Perovskite; Photocatalysis
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2017.11.035

[Display omitted] •Uniform perovskite hydroxide CoSn(OH)6 nanocubes are synthesized by a facile one-pot co-precipitation method.•For the first time, the CoSn(OH)6 nanocubes are demonstrated as cost-affordable, highly efficient and stable catalysts for deoxygenative reduction of CO2 to CO with visible light.•The CoSn(OH)6 material manifests a high CO evolution rate of 18.7μmolh−1 together with high stability and reusability.•The CoSn(OH)6 catalyst effectively promotes the separation and migration of photoexcited charge carriers during CO2 photoreduction catalysis. 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 CO2 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 N2 sorption measurements. The CoSn(OH)6 solid is found by theoretical calculations to be capable of absorbing and activating CO2 molecules on the (100) surface. Under the optimal reaction conditions, the CoSn(OH)6 catalyst exhibits a high CO2 reduction activity with visible light irradiation, affording a CO generation rate of 18.7μmolh−1. The stability and reusability of the CoSn(OH)6 catalyst for photocatalytic CO2 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 CO2 photoreduction performance. Moreover, a possible mechanism for the photocatalytic CO2 reduction reaction is also proposed based on the results of activity evaluation and photo-/electro-chemical measurements.