Fig. 4: Cation-dependent and pH-dependent HER kinetics on Au RDE electrode.
From: Effect of ion-specific water structures at metal surfaces on hydrogen production
a–c HER polarization curves on Au surface in acidic, neutral and alkaline electrolytes, respectively, measured at 10 mV s−1 and 2500 rpm in H2-saturated aqueous electrolytes of 0.1 M HClO4 and 0.1 M perchlorate salt of Li, Na, K or 0.05 M perchlorate salt of Cs (pH1), aqueous solutions of 0.05–0.1 M MClO4 (M=Li, Na, K and Cs) (pH6-7), and aqueous electrolytes of 0.1 M hydroxide of Li, Na, K and Cs (pH13). The zoom-in of low overpotential region can be found in Supplementary Fig. 13. d The exchange current density extracted by MHC formalism (Supplementary Fig. 15). e The reorganization energy extracted by MHC formalism and interfacial static dielectric constant extracted via Born model of reorganization energy. f The reorganization energy of HER on Au RDE as a function of the relative fraction of isolated water in OH stretching peak at −0.2 VRHE for acidic, neutral and alkaline electrolytes. All CV data has been iR corrected. The non-iR corrected HER polarization curves are shown in Supplementary Fig. 16. Error bars were obtained from the standard deviation of 2–3 independent measurements.
