Pt–Ni octahedral nanocrystals as a class of highly active electrocatalysts toward the hydrogen evolution reaction in an alkaline electrolyte

We have synthesized Pt–Ni octahedral nanocrystals with Ni(OH)2 naturally formed on their surfaces as a promising catalyst for the hydrogen evolution reaction (HER) in an alkaline solution. For Pt–Ni octahedra of 9 nm in size, they exhibited specific and mass HER activities 15 times and 4.6 times greater than those of a commercial Pt/C catalyst in 0.1 M KOH solution.