Fig. 5. HBE and OHBE.

a UPS spectra of MoNi₄, WNi₄, and freshly synthesized Ni catalysts. b CO-stripping measurements on MoNi₄, WNi₄, and freshly synthesized Ni and Pt/C catalysts. Sweep rate: 20 mV s⁻¹. Rotation speed: 1600 r.p.m. The gray curves in b show the second cycle of the measurements. c The experimentally measured exchange current density normalized by ECSA, log(j₀), for the HOR in 0.1 M KOH on different catalysts plotted with the calculated H and OH binding energies. d–f Schematic illustration of hydrogen and hydroxyl adsorption on freshly synthesized Ni, Mo(W)Ni₄ alloys, and Pt, respectively.