Fig. 1: Morphology and structure characterizations.

a TEM and b HAADF-STEM images of the CR-Co/ClNC catalyst. TEM-EDS mapping images for c CR-Co/ClNC and d Co/NC. e FT-EXAFS spectra of the Co K-edge for the CR-Co/ClNC catalyst and reference samples, and the corresponding fitting curves for CR-Co/ClNC and Co/NC. The inset shows Cl, Co, N, and C atoms indicated by cyan, purple, dark blue, and gray.