Using Anion‐Exchange to Induce the Formation of Edge Defects in CoNx to Enhance ORR Activity

Abstract

AbstractDeveloping high‐efficiency non‐noble metal based electrocatalysts to promote oxygen reduction reaction (ORR) is critical for the popularization of energy conversion devices. Herein, a facile anion exchange‐pyrolysis two‐step strategy is reported to synthesize hierarchical CoNx/Co@NC electrocatalyst with abundant edge defects. The introduction of edge defects not only alter the configuration of N species in carbon skeleton, but also can effectively trap metal Co atoms to form CoNx sites that can afford more adsorption sites for oxygen molecules. Furthermore, the incorporation of edge defects can trigger the change of electronic structure CoNx/Co@NC, which optimize the binding energy between oxygen intermediates and catalysts. Benefit from the increased active sites and the optimized electronic structure, the obtained edge defects‐rich CoNx/Co@NC demonstrates superior electrocatalytic activity, high durability and methanol tolerance with negligible decay after 40000 s, superior to Co@NC and commercial Pt/C. This job offers a valid anion exchange strategy for designing highly active non‐noble metal electrocatalysts for ORR.