Effect of the structure of Ni nanoparticles on the electrocatalytic activity of Ni@Pd/C for formic acid oxidation

► The Ni@Pt/C catalysts with different crystallization of Ni core were prepared. ► Niamorphous@Pd/C has higher activity than Nicrystal@Pd/C for formic acid oxidation. ► The structure of core affects the electrocatalytic activity of electrocatalysts.