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Low-coordinated Ni-N1-C3 sites atomically dispersed on hollow carbon nanotubes for efficient CO2 reduction

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Abstract

Low-coordinated single atom catalysts compared to M-N4 are appealing in optimized electronic structure for CO2 electro-reduction, but the preparation is still very challenging. Herein, a novel single Ni atom catalyst with Ni-N1-C3 configuration is in-situ evolved on curved carbon nanotubes. The obtained Ni-N1-C3 catalyst exhibits a superior CO Faradaic efficiency of 97% and turnover frequency of 2,890 h−1 at −0.9 V versus the reversible hydrogen electrode, as well as long-term stability over 45 h. High current densities exceeding 200 mA·cm−2 and CO Faradaic efficiency of 99% are achieved in flow-cell. Moreover, in-situ potential-and time-dependent Raman spectra identify the key intermediates of *COOH and *CO during CO2-to-CO conversion. Theoretical calculations reveal that the upward-shifted d-band center and charge-rich Ni sites of Ni-N1-C3 facilitate the electron transfer to *COOH and thus reduce the *COOH formation energy barrier. This work demonstrates a strategy for modulating the coordination environment for efficient CO2 reduction.

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Acknowledgements

This research work was supported by the National Natural Science Foundation of China (Nos. 21908090, 22008101, 22108243, and 22168023) and the Natural Science Foundation of Jiangxi Province (No. 20212BAB213038). Y. F. acknowledges the 2020 Nanchang University Scholarship for Doctoral Visiting Abroad.

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Authors and Affiliations

  1. School of Resource and Environment, Nanchang University, Nanchang, 330031, China

    Fangqi Yang

  2. Chemistry and Chemical Engineering School, Nanchang University, Nanchang, 330031, China

    Fangqi Yang, Haoming Yu, Yun Su, Jingwen Chen, Shixia Chen, Zheling Zeng & Jun Wang

  3. School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, 85287, USA

    Shuguang Deng

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  1. Fangqi Yang
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Yang, F., Yu, H., Su, Y. et al. Low-coordinated Ni-N1-C3 sites atomically dispersed on hollow carbon nanotubes for efficient CO2 reduction. Nano Res. 16, 146–154 (2023). https://doi.org/10.1007/s12274-022-4623-9

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