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Selectivity control of CO versus HCOO− production in the visible-light-driven catalytic reduction of CO2 with two cooperative metal sites

Nature Catalysis volume 2, pages 801–808 (2019)Cite this article

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A Publisher Correction to this article was published on 28 August 2019

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Abstract

It is highly desirable to discover molecular catalysts with controlled selectivity for visible-light-driven CO2 reduction to fuels. In the design of catalysts employing earth-abundant metals, progress has been made for CO production, but formate generation has been observed more rarely. Here, we report a binuclear Co complex bearing a bi-quaterpyridine ligand that can selectively reduce CO2 to HCOO− or CO under visible light irradiation. Selective formate production (maximum of 97%) was obtained with a turnover number of up to 821 in basic acetonitrile solution. Conversely, in the presence of a weak acid, CO2 reduction affords CO with high selectivity (maximum of 99%) and a maximum turnover number of 829. The catalytic process is controlled by the two Co atoms acting synergistically, and the selectivity can be steered towards the desired product by simply changing the acid co-substrate.

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Fig. 1: Structure of compounds used in this study.
Fig. 2: Crystal structure of [Co2(biqpy)Cl(MeOH)(H2O)]3+.
Fig. 3: Photocatalytic CO2 reduction products.
Fig. 4: CV plots and infrared SEC spectra.
Fig. 5: Proposed mechanism for visible-light-driven catalytic reduction of CO2 into CO and HCOO− with catalyst 1.

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Data availability

Crystallographic data for [Co2(biqpy)Cl(MeOH)(H2O)](ClO4)3 have been deposited at the Cambridge Crystallographic Data Centre (CCDC no. 1858669. The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.

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  • 28 August 2019

    An amendment to this paper has been published and can be accessed via a link at the top of the paper.

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Acknowledgements

The work described in this project was supported by the National Science Foundation of China (grant no. 21703034), Hong Kong University Grants Committee Area of Excellence Scheme (grant no. AoE/P-03–08), Hong Kong Research Grants Council (N_CityU115/18) and the French National Agency for Research (ANR-16-CE05-0010-01). G.C. acknowledges start-up grants from Dongguan University of Technology for high-level talents (grant nos G200906-47, GC200109-17 and KCYKYQD2017016). K.C.L. and M.R. acknowledge partial financial support from CityU Strategic Research Grant no. 7004819 and from the Institut Universitaire de France (IUF), respectively. PhD fellowships to C.C. from Université Sorbonne Paris Cité (USPC) and to B.M. from the China Scholarship Council (CSC student no. 201707040042) are acknowledged. G. Thoraval (Université Paris Diderot) is thanked for the design and preparation of the glassy carbon electrode (3 mm diameter) used during CV experiments. Finally, we thank G. Miyake (Colorado State University) for the sample gift of phenoxazine (Pheno).

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  1. These authors contributed equally: Zhenguo Guo, Gui Chen, Claudio Cometto, Bing Ma.

Authors and Affiliations

  1. School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, Guangdong, China

    Zhenguo Guo, Gui Chen, Lingjing Chen & Hongbo Fan

  2. Department of Chemistry and Institute of Molecular Functional Materials, City University of Hong Kong, Kowloon Tong, Hong Kong, China

    Zhenguo Guo, Hongyan Zhao, Shek-Man Yiu, Kai-Chung Lau & Tai-Chu Lau

  3. Université de Paris, Laboratoire d’Electrochimie Moléculaire, CNRS, Paris, France

    Claudio Cometto, Bing Ma, Thomas Groizard & Marc Robert

  4. Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China

    Wai-Lun Man

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Contributions

G.C., K.-C.L., M.R. and T.-C.L. conceived and supervised the project. G.C., L.C. and H.F. designed and synthesized the catalysts. W.-L.M. and S.-M.Y. characterized the structure of catalyst 1. Z.G., C.C. and B.M. carried out the CO2 reduction experiments. C.C. performed the spectro-electrochemistry experiments. H.Z. and T.G. carried out the DFT calculations. All authors discussed the results and assisted during manuscript preparation.

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Correspondence to Kai-Chung Lau, Tai-Chu Lau or Marc Robert.

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Supplementary Information

Supplementary methods, Supplementary Figs. 1–30, Supplementary Tables 1–8, Supplementary references

Compound 1

Crystallographic data for compound 1.

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Guo, Z., Chen, G., Cometto, C. et al. Selectivity control of CO versus HCOO− production in the visible-light-driven catalytic reduction of CO2 with two cooperative metal sites. Nat Catal 2, 801–808 (2019). https://doi.org/10.1038/s41929-019-0331-6

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