fig9

Figure 9. (A) XPS spectra performed on the Mo/Ni₃N/Ni and Ni₃N/Ni powder scratched off the Ni foam. High-resolution XPS spectra of Mo/Ni₃N/Ni for (A) Ni 2p, (B) N 1s, and (C) Mo 3d, respectively; High-resolution XPS spectra of Mo/Ni3N/Ni after Ar ion etching for Ni 2p, N 1s and Mo 3d, respectively; (B) The investigation on HzOR and HER activity for Mo/Ni₃N/Ni/NF LSV curves and (C) Tafel plots of different catalysts toward HzOR (D) I-t test for Mo/Ni₃N/Ni/NF toward HzOR (up) measured at the work potential of 124 mV and HER (down) at the work potential of 68 mV, both without iR correction; (E) The density of states and (F) Charge density difference and planar-averaged electron density difference of Mo-Ni₃N/Ni; (G) Gibbs free energy profiles for the stepwise dehydrogenation process of N2H4 with solvent interactions on Mo-Ni₃N/Ni, Ni₃N/Ni, and Ni₃N^[144]. This figure is quoted with permission from Liu et al. XPS: X-ray photoelectron spectroscopy; HER: hydrogen evolution reaction; LSV: linear sweep voltammetry.