Strategies for the regulation of specific active sites in metal−nitrogen−carbon

The most advanced electrocatalysts still rely heavily on traditional precious metal-based nanoparticles, which are scarce and high-cost. The metal−nitrogen−carbon (M−N−C) catalysts which have relatively low cost and excellent catalytic performance, are emerging as the most promising replacements for the current best performing precious metal-based catalysts. In this review, we summarize the effects of different coordination structures of the M−N−C on their electrocatalytic performance. We then analyze the synthetic strategies for regulation of the specific MNx coordination structure in M−N−C. Improvement strategies are also given for increasing catalyst activity and stability. Finally, we discuss the challenges of preparing M−N−C with specific MNx active sites and express M−N−C perspective for the use of green renewable energy in the future. This review will guide and promote the design of effective electrocatalysts with specific active sites.