Ir/Ni–NiO/CNT composites as effective electrocatalysts for hydrogen oxidation

Ir/Ni–NiO/CNT composite catalyst for hydrogen oxidation is designed, which shows a high mass activity of 1.59 mA μg Ir −1 in 0.1 M KOH. The presence of Ni–NiO weakens the hydrogen binding energy on Ir sites, and thus facilitates the Volmer step.