Figure 1.

Cyclic voltammograms obtained for HER on a) Au polycrystalline surface and b) Au(111) surface at 2500 rpm in 0.001 M NaOH (pH 11) for different concentrations of NaClO₄ (5 mM, 250 mM, 500 mM and 1000 mM) in Ar‐saturated environment at 25 mV s⁻¹.