Graphical Abstract

Efficient electroreduction of CO2 into CO and other chemicals turns greenhouse gases into fuels and value-added chemicals, holding great promise for a closed carbon cycle and the alleviation of climate changes. However, there are still challenges in the large-scale application of CO2 electroreduction due to the sluggish kinetics. Herein we develop a self-assembly strategy to synthesize a highly efficient CO2 reduction electrocatalyst with atomically dispersed Ni-N4 active centers anchored on polymer-derived mesh-like N-doped carbon nanofibers (Ni-N4/NC). The Ni-N4/NC exhibits high selectivity for CO2 reduction reaction with CO Faradaic efficiency (CO FE) above 90% over a wide potential range from −0.6 to −1.0 V vs. RHE. The catalyst reaches a maximum CO FE up to 98.4% at −0.8 V with a TOF of 1.28 x 105 h–1 and Tafel slope of 113 mV·dec–1. The catalyst also exhibits remarkable stability, with little change in current density and CO FE over a 10-hour durability test at –0.8 V vs. RHE. This method provides a new route for the synthesis of highly efficient CO2 reduction electrocatalyst.
Gu, J.; Hsu, C. S.; Bai, L. C.; Chen, H. M.; Hu, X. L. Atomically dispersed Fe3+ sites catalyze efficient CO2 electroreduction to CO. Science 2019, 364, 1091–1094.
Nitopi, S.; Bertheussen, E.; Scott, S. B.; Liu, X. Y.; Engstfeld, A. K.; Horch, S.; Seger, B.; Stephens, I. E. L.; Chan, K.; Hahn, C. et al. Progress and perspectives of electrochemical CO2 reduction on copper in aqueous electrolyte. Chem. Rev. 2019, 119, 7610–7672.
Zheng, T. T.; Jiang, K.; Wang, H. T. Recent advances in electrochemical CO2-to-CO conversion on heterogeneous catalysts. Adv. Mater. 2018, 30, 1802066.
Birdja, Y. Y.; Pérez-Gallent, E.; Figueiredo, M. C.; Göttle, A. J.; Calle-Vallejo, F.; Koper, M. T. M. Advances and challenges in understanding the electrocatalytic conversion of carbon dioxide to fuels. Nat. Energy 2019, 4, 732–745.
Su, X.; Yang, X. F.; Huang, Y. Q.; Liu, B.; Zhang, T. Single-atom catalysis toward efficient CO2 conversion to CO and formate products. Acc. Chem. Res. 2019, 52, 656–664.
Chen, W. Y.; Liu, X. M.; Han, B.; Liang, S. J.; Deng, H.; Lin, Z. Boosted photoreduction of diluted CO2 through oxygen vacancy engineering in NiO nanoplatelets. Nano Res. 2020, 14, 730–737.
Liang, S. J.; Liu, X. M.; Zhong, Z. Q.; Han, B.; Zhong, X. H.; Chen, W. Y.; Song, K. N.; Deng, H.; Lin, Z. Lattice-strained nanotubes facilitate efficient natural sunlight-driven CO2 photoreduction. Nano Res. 2020, 14, 2558–2567.
Lin, R.; Ma, X. L.; Cheong, W. C.; Zhang, C.; Zhu, W.; Pei, J. J.; Zhang, K. Y.; Wang, B.; Liang, S. Y.; Liu, Y. X. et al. PdAg bimetallic electrocatalyst for highly selective reduction of CO2 with low COOH* formation energy and facile CO desorption. Nano Res. 2019, 12, 2866–2871.
Zhang, N. Q.; Zhang, X. X.; Tao, L.; Jiang, P.; Ye, C. L.; Lin, R.; Huang, Z. W.; Li, A.; Pang, D. W.; Yan, H. et al. Silver single-atom catalyst for efficient electrochemical 2 reduction synthesized from thermal transformation and surface reconstruction. Angew. Chem., Int. Ed. 2021, 60, 6170–6176.
Corbin, N.; Zeng, J.; Williams, K.; Manthiram, K. Heterogeneous molecular catalysts for electrocatalytic CO2 reduction. Nano Res. 2019, 12, 2093–2125.
Jiang, Z. L.; Wang, T.; Pei, J. J.; Shang, H. S.; Zhou, D. N.; Li, H. J.; Dong, J. C.; Wang, Y.; Cao, R.; Zhuang, Z. B. et al. Discovery of main group single Sb-N4 active sites for CO2 electroreduction to formate with high efficiency. Energy Environ. Sci. 2020, 13, 2856–2863.
Cheng, Y.; Veder, J. P.; Thomsen, L.; Zhao, S. Y.; Saunders, M.; Demichelis, R.; Liu, C.; De Marco, R.; Jiang, S. P. Electrochemically substituted metal phthalocyanines, e-MPc (M = Co, Ni), as highly active and selective catalysts for CO2 reduction. J. Mater. Chem. A 2018, 6, 1370–1375.
Chen, J. Y.; Wang, T. T.; Li, Z. J.; Yang, B.; Zhang, Q. H.; Lei, L. C.; Feng, P. Y.; Hou, Y. Recent progress and perspective of electrochemical CO2 reduction towards C2-C5 products over non-precious metal heterogeneous electrocatalysts. Nano Res. 2021, 14, 3188–3207.
Sorokin, A. B. Phthalocyanine metal complexes in catalysis. Chem. Rev. 2013, 113, 8152–8191.
Zhang, X.; Wang, Y.; Gu, M.; Wang, M. Y.; Zhang, Z. S.; Pan, W. Y.; Jiang, Z.; Zheng, H. Z.; Lucero, M.; Wang, H. L. et al. Molecular engineering of dispersed nickel phthalocyanines on carbon nanotubes for selective CO2 reduction. Nat. Energy 2020, 5, 684–692.
Ma, Z. J.; Zhang, X. L.; Han, X. Y.; Wu, D. P.; Wang, H. J.; Gao, Z. Y.; Xu, F.; Jiang, K. Synergistic adsorption and activation of nickel phthalocyanine anchored onto ketjenblack for CO2 electrochemical reduction. Appl. Surf. Sci. 2021, 538, 148134.
Pan, Y.; Lin, R.; Chen, Y. J.; Liu, S. J.; Zhu, W.; Cao, X.; Chen, W. X.; Wu, K. L.; Cheong, W. C.; Wang, Y. et al. Design of single-atom Co-N5 catalytic site: A robust electrocatalyst for CO2 reduction with nearly 100% CO selectivity and remarkable stability. J. Am. Chem. Soc. 2018, 140, 4218–4221.
Pan, Y.; Liu, S. J.; Sun, K. A.; Chen, X.; Wang, B.; Wu, K. L.; Cao, X.; Cheong, W. C.; Shen, R. A.; Han, A. J. et al. A bimetallic Zn/Fe polyphthalocyanine-derived single-atom Fe-N4 catalytic site: A superior trifunctional catalyst for overall water splitting and Zn-air batteries. Angew. Chem., Int. Ed. 2018, 57, 8614–8618.
Yang, X.; Cheng, J.; Fang, B. Z.; Xuan, X. X.; Liu, N.; Yang, X.; Zhou, J. H. Single Ni atoms with higher positive charges induced by hydroxyls for electrocatalytic CO2 reduction. Nanoscale 2020, 12, 18437–18445.
Zhang, Y.; Jiao, L.; Yang, W. J.; Xie, C. F.; Jiang, H. L. Rational fabrication of low-coordinate single-atom Ni electrocatalysts by mofs for highly selective CO2 reduction. Angew. Chem., Int. Ed. 2021, 133, 7686–7689.
Fan, Q.; Hou, P. F.; Choi, C.; Wu, T. S.; Hong, S.; Li, F.; Soo, Y. L.; Kang, P.; Jung, Y.; Sun, Z. Y. Activation of Ni particles into single Ni-N atoms for efficient electrochemical reduction of CO2. Adv. Energy Mater. 2020, 10, 1903068.
Zheng, T. T.; Jiang, K.; Ta, N.; Hu, Y. F.; Zeng, J.; Liu, J. Y.; Wang, H. T. Large-scale and highly selective CO2 electrocatalytic reduction on nickel single-atom catalyst. Joule 2019, 3, 265–278.
Prslja, P.; López, N. Stability and redispersion of Ni nanoparticles supported on N-doped carbons for the CO2 electrochemical reduction. ACS Catal. 2021, 11, 88–94.
Cheng, Y.; Zhao, S. Y.; Johannessen, B.; Veder, J. P.; Saunders, M.; Rowles, M. R.; Cheng, M.; Liu, C.; Chisholm, M. F.; De Marco, R. et al. Atomically dispersed transition metals on carbon nanotubes with ultrahigh loading for selective electrochemical carbon dioxide reduction. Adv. Mater. 2018, 30, 1706287.
Li, X. G.; Bi, W. T.; Chen, M. L.; Sun, Y. X.; Ju, H. X.; Yan, W. S.; Zhu, J. F.; Wu, X. J.; Chu, W. S.; Wu, C. Z. et al. Exclusive Ni-N4 sites realize near-unity CO selectivity for electrochemical CO2 reduction. J. Am. Chem. Soc. 2017, 139, 14889–14892.
Tan, D. X.; Zhang, J. L.; Yao, L.; Tan, X. N.; Cheng, X.; Wan, Q.; Han, B. X.; Zheng, L. R.; Zhang, J. Multi-shelled CuO microboxes for carbon dioxide reduction to ethylene. Nano Res. 2020, 13, 768–774.
Jiang, K.; Siahrostami, S.; Zheng, T. T.; Hu, Y. F.; Hwang, S.; Stavitski, E.; Peng, Y. D.; Dynes, J.; Gangisetty, M.; Su, D. et al. Isolated Ni single atoms in graphene nanosheets for high-performance CO2 reduction. Energy Environ. Sci. 2018, 11, 893–903.
Xiong, W. F.; Li, H. F.; Wang, H. M.; Yi, J. D.; You, H. H.; Zhang, S. Y.; Hou, Y.; Cao, M. N.; Zhang, T.; Cao, R. Hollow mesoporous carbon sphere loaded Ni-N4 single-atom: Support structure study for CO2 electrocatalytic reduction catalyst. Small 2020, 16, 2003943.
Cao, T.; Wang, D. S.; Zhang, J. T.; Cao, C. B.; Li, Y. D. Bamboo-like nitrogen-doped carbon nanotubes with Co nanoparticles encapsulated at the tips: Uniform and large-scale synthesis and high-performance electrocatalysts for oxygen reduction. Chemistry 2015, 21, 14022–14029.
Rong, X.; Wang, H. J.; Lu, X. L.; Si, R.; Lu, T. B. Controlled synthesis of a vacancy-defect single-atom catalyst for boosting CO2 electroreduction. Angew. Chem., Int. Ed. 2020, 59, 1961–1965.