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Recent Advances in Non-Precious Metal–Nitrogen–Carbon Single-Site Catalysts for CO2 Electroreduction Reaction to CO

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Abstract

The carbon dioxide electroreduction reaction (CO2RR) to fuels and/or chemicals is an efficient prospective strategy to realize global carbon management using intermittent electric energy harvested from renewable sources. Highly efficient inexpensive electrocatalysts are required to achieve high energy and Faradaic efficiencies as well as fast conversion. Metal–nitrogen–carbon (M–N–C) single-site catalysts (SSCs) are highly competitive over precious metal catalysts in the CO2RR to CO due to their high performance, easy regulation and low cost. In the past six years, intensive studies of M–N–C SSCs for CO2RR to CO have been performed, and great progress has been achieved. This review focuses on the important topic of CO2RR to CO with M–N–C SSCs. We first introduce the reaction mechanism of the CO2RR to CO and the regulation of the electronic structure from a theoretical viewpoint. Then, the construction of M–N–C SSCs and the regulation of the electronic structure are demonstrated experimentally. The up-to-date electrocatalytic performance of M–N–C SSCs with different metal centers (Ni, Fe, Co and others) is summarized and compared systematically to highlight structure–performance correlations that were considered from both theoretical and experimental perspectives. Finally, the opportunities, challenges and future outlooks are summarized to deepen and widen research and applications in this promising field.

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Scheme 1
Fig. 1

Copyright 2018, American Chemical Society

Fig. 2

Reproduced from Ref. [79] with permission. Copyright 2019, Wiley–VCH. b The model of Fe–N4–C, Fe–N4–C coated on Fe2N (001), and corresponding free energy profiles for CO2RR. Reproduced from Ref. [80] with permission. Copyright 2018, American Chemical Society. c The M–N4–C10 and M–N2+2–C8 (M = Fe or Co) active sites and their *COOH dissociation free energy evolution. Reproduced from Ref. [102] with permission. Copyright 2018, American Chemical Society. d Co–N5 moiety and corresponding calculated free energy (uncountable) during the CO2RR. The short red line is the desorption free energy level of CO, and the red dashed line is the desorption free energy of CO. Reproduced from Ref. [105] with permission. Copyright 2018, American Chemical Society. e Ni–N–C and S-doped Ni–N–C on hierarchical carbon nanocages (i.e., Ni–N–hCNCs and Ni–SN–hCNCs, respectively) and corresponding free energy profiles for the CO2RR. Reproduced from Ref. [109] with permission. Copyright 2020, Springer

Fig. 3

Reproduced from Ref. [112] with permission. Copyright 2020, Elsevier. The assembly of NiPc–COF via the condensation reaction. Reproduced from Ref. [113] with permission. Copyright 2020, Wiley–VCH. b The assembly of NiPor–CTF via the ionothermal strategy. 1 M = 1 mol L−1, 1 Å = 1 × 10−10 m. Reproduced from Ref. [120] with permission. Copyright 2018, Wiley–VCH

Fig. 4

Reproduced from Ref. [125] with permission. Copyright 2020, Royal Society of Chemistry. b The coordination of metal cations with the 1D molecular chains of formamide for the production of M–N–C SSCs by pyrolysis. Reproduced from Ref. [130] with permission. Copyright 2019, Royal Society of Chemistry. c The synthetic route of the carbon nanosheets with Ni–Nx sites by pyrolyzing the mixture of citric acid, Ni(NO3)2 and melamine. Reproduced from Ref. [131] with permission. Copyright 2020, Elsevier. d Schematic of a MnOx-induced strategy to construct Fe–N–C SSCs with highly exposed active sites. Reproduced from Ref. [133] with permission. Copyright 2016, Royal Society of Chemistry

Fig. 5

Reproduced from Ref. [141] with permission. Copyright 2019, Wiley–VCH. b N-free MEGO as a support. Reproduced from Ref. [128] with permission. Copyright 2019, Elsevier. c Commercially available carbon black. Reproduced from Ref. [127] with permission. Copyright 2020, Royal Society of Chemistry

Fig. 6

Reproduced from Ref. [150] with permission. Copyright 2017, American Chemical Society. b A self-sacrifice ZnO template approach to produce Ni–N–C SSC in the form of porous nanotubes by the pyrolysis of ZnO@Ni–ZIF core–shell nanorods. Reproduced from Ref. [174] with permission. Copyright 2020, Elsevier

Fig. 7

Reproduced from Ref. [178] with permission. Copyright 2019, Springer. b The formation of the Ni–NC@Ni core–shell catalyst by the reaction of gaseous urea with NiO nanosheets. Reproduced from Ref. [180] with permission. Copyright 2020, Elsevier

Fig. 8

Reproduced from Ref. [50] with permission. Copyright 2018, Nature Publishing Group. The operando Raman spectra under atmosphere of e CO2 and f Ar. Reproduced from Ref. [107] with permission. Copyright 2020, Wiley–VCH

Fig. 9

Reproduced from Ref. [96] with permission. Copyright 2018, Royal Society of Chemistry. b Faradaic efficiency of CO and H2 for the Ni–N–C SSC from Ni–ZIF. The N–C catalyst is the control sample. Reproduced from Ref. [175] with permission. Copyright 2019, Royal Society of Chemistry. c FECO for the Ni–N–C SSC from Ni–CTF. The Co–CTF, Cu–CTF, and CTF catalysts are the control samples. Reproduced from Ref. [119] with permission. Copyright 2019, Royal Society of Chemistry. d FECO of NiFe–N–C. The Ni–N–C and Fe–N–C catalysts are the control samples. Reproduced from Ref. [79] with permission. Copyright 2019, Wiley–VCH. e FECO of Ni–N3–V. The Ni–N4 and NC catalysts are the control samples. Reproduced from Ref. [151] with permission. Copyright 2020, Wiley–VCH. f FECO of Ni–N4–O/C. The Ni–N4/C and NC catalysts are the control samples. Reproduced from Ref. [199] with permission. Copyright 2020, Wiley–VCH. Comparison of the g FECO and h CO partial current density of Ni–SN–hCNCs and Ni–N–hCNCs. i Stability test of the Ni–SN–hCNCs. Reproduced from Ref. [109] with permission. Copyright 2020, Springer

Fig. 10

Reproduced from Ref. [51] with permission. Copyright 2019, American Association for the Advancement of Science (AAAS). The operando Fe K-edge XANES c and EXAFS d. Reproduced from Ref. [77] with permission. Copyright 2018, Royal Society of Chemistry

Fig. 11

Reproduced from Ref. [217] with permission. Copyright 2019, Springer. b FECO for FeN4/C prepared by the pyrolysis of Fe-adsorbed g–C3N4. The N/C and Fe/C catalysts are the control samples. Reproduced from Ref. [154] with permission. Copyright 2020, Elsevier

Fig. 12

Reproduced from Ref. [233] with permission. Copyright 2017, Wiley–VCH. b Faradaic efficiency (CO, H2) and current density at − 0.63 V of the CoPc/CNT prepared by the direct adsorption of CoPc on CNT. Reproduced from Ref. [158] with permission. Copyright 2017, Nature Publishing Group. c Faradaic efficiency (CO, H2) of the Co–N–C SSC derived from the Co-containing COF-366. 1 h and 2 h are the reaction times. Reproduced from Ref. [52] with permission. Copyright 2015, AAAS. d Faradaic efficiency (CO, H2) of the Co–N–C SSC derived from Co-adsorbed ZIF-8. Reproduced from Ref. [235] with permission. Copyright 2020, Elsevier. e FECO and corresponding potential of the hybridized ZnCo–N–C catalyst. Zn–N–C and Co–N–C are the control samples. Reproduced from Ref. [238] with permission. Copyright 2019, Wiley–VCH. f TOFCO of the S-doped NapCo@SNG. NapCo@NG and NapCo@OG are the control samples. Reproduced from Ref. [159] with permission. Copyright 2019, Wiley–VCH

Fig. 13

Reproduced from Ref. [239] with permission. Copyright 2019, Nature Publishing Group. b The Faradaic efficiency (formate, CO, H2) of Sn–N4F–C and c Faradaic efficiency (H2, CO) of Sn–C2O2F–C. Reproduced from Ref. [240] with permission. Copyright 2021, American Chemical Society. d The Faradaic efficiency (H2, CO, ethanol) of Cu–N4–C. Reproduced from Ref. [161] with permission. Copyright 2019, Wiley–VCH. e The Faradaic efficiency (H2, C2H4, CO, CH4) and current density of Cu–N2O2–C. Reproduced from Ref. [241] with permission. Copyright 2021, Nature Publishing Group. f The Faradaic efficiency (CH4, H2) and current density of Zn–N4–C. Reproduced from Ref. [162] with permission. Copyright 2020, American Chemical Society

Fig. 14

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Data Availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Code availability

The code that support the findings of this study are available from the corresponding author upon reasonable request.

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Acknowledgements

This work was jointly supported by the National Key Research and Development Program of China (2017YFA0206500, 2018YFA0209103, 2021YFA1500900), the National Natural Science Foundation of China (21832003, 21773111, 21972061, 52071174), the Leading-edge Technology Program of Jiangsu Natural Science Foundation (BK20212005) and the Nan**g University Innovation Program for the PhD candidate (No. CXYJ21-38).

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  1. Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nan**g University, Nan**g, 210023, Jiangsu, China

    Yiqun Chen, Junru Zhang, Lijun Yang, **zhang Wang, Qiang Wu & Zheng Hu

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  4. **zhang Wang
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  5. Qiang Wu
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  6. Zheng Hu
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Contributions

Y. Chen, J. Zhang: Investigation, data curation, writing original draft, writing & Review & Editing. L. Yang, X. Wang: Writing & Review & Editing, supervision, funding acquisition. Q. Wu, Z. Hu: Conceptualization, writing & Review & Editing, supervision, project administration, funding acquisition.

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Correspondence to Qiang Wu or Zheng Hu.

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The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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I hereby declare that this manuscript is the result of my independent creation under the reviewer’s comments. Except for the quoted contents. this manuscript does not contain any research achievements that have been published or written by other individuals or groups. I am the only author of this manuscript. The legal responsibility of this statement shall be borne by me.

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Chen, Y., Zhang, J., Yang, L. et al. Recent Advances in Non-Precious Metal–Nitrogen–Carbon Single-Site Catalysts for CO2 Electroreduction Reaction to CO. Electrochem. Energy Rev. 5, 11 (2022). https://doi.org/10.1007/s41918-022-00156-4

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  • DOI: https://doi.org/10.1007/s41918-022-00156-4

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