fig2

Figure 2. (A) Illustration of Co₉S₈/CoNSC^[89]; (B) Illustration of Cu₃P/MoP@C; (C) Structural characterization of Cu₃P/MoP@C, Cu₃P@C, MoP@C^[97]; (D) Illustration and morphology characterization of A-MnO₂/NSPCs; (E) Optimized structures for the adsorbed O atom on A-MnO₂/NSPC and NSPC, DOS and the free energies versus the reaction coordinates toward ORR on NSPC and A-MnO₂/NSPC; (F) High-resolution XPS spectra: N 1s, S 2p, and P 2p of A-MnO₂/NSPC-2^[98]. NSPC: N, S, P co-doped carbon sphere; OER: oxygen evolution reaction; HER: hydrogen evolution reaction; ORR: oxygen reduction reaction; DOS: density of states; XPS: X-ray photoelectron spectroscopy; N: nitrogen; S: sulfur; P: phosphorus.