Figure 6

(a) X-ray absorption near-edge spectra (XANES) of the Ni K edge (E ₀ = 8333 eV) with a valence states (inset figure), (b) X-ray photoelectron spectra (XPS) of the Ni 2p level before (left) and after the OER (right), and (c) extended X-ray absorption fine structure (EXAFS) and structural correlation of Ni₂P/C after the OER.