6 Conclusion
Due to the affordable price, good stability, high activity and selectivity, Ni-N-C materials are regarded as the promising ECR catalysts. In this review, the recent progress of Ni-N-C materials toward ECR was systematically summarized. Based on the transformation mechanism of CO2 to CO and the existence of Ni species in three forms (nanoparticles, single atoms, and both), the effects on catalytic activity, stability and selectivity from multiple regulation strategies such as coordination environment, microstructure morphology, defect engineering, surface modification, activation of heteroatoms, bimetallic sites et al., were discussed in detail. These positive efforts have exhibited powerful impetus and hope for the ECR development, and facilitate the exploration of other M-N-C materials. In addition, according to the current researches, we put forward the urgent need to overcome the core problems and technical barriers that reasonable solution will certainly promote the optimization of energy structure. We hope this review will provide a solid basis and help for the development of CO2 emission reduction technologies and developing excellent electrocatalysts. To sum up, with the progress of science and technologies, the targets of carbon dioxide emission peak and carbon neutrality will be realized.
Acknowledgements
Q. Pang and X. Fan contributed equally to this work. This work was financially supported by the National Natural Science Foundation of China (22278380, 22108259), China Postdoctoral Science Foundation (2021M692911, 2022T150589).