Periodic Variations of Overvoltages for Water Electrolysis in Acid Solutions from Cyclic Voltammetric Studies

Cyclic voltammetry was used to determine the electrocatalytic activities of 31 metals for the hydrogen and oxygen evolution reaction in at 80°C. For the hydrogen evolution reaction, properties of the metals such as electronic structures, work functions, and metal‐hydrogen bond strengths tend to correlate with the observed electrocatalytic activities. The best electrocatalysts for the hydrogen evolution reaction in the order of decreasing catalytic activity are . For the oxygen evolution reaction, the order of catalytic activity is . Most other metals undergo anodic corrosion and cannot be used for the evolution of oxygen in acid solutions. The potentials at which corrosion is observed are presented for these metals.