Fig. 3: Coordination environment of active sites.

High-resolution XPS spectra of Co 2p (a), Fe 2p (b) and P 2p (c). K-edge XANES spectra of Co (d) and Fe (e) for catalysts and reference compounds. EXAFs results of Co K-edge (f) and Fe K-edge (g) for catalysts and reference compounds. h Coordination environment of active sites in different catalysts. Source data for a–g are provided as a Source Data file.