Crystallinity‐Modulated Electrocatalytic Activity of a Nickel(II) Borate Thin Layer on Ni3B for Efficient Water Oxidation

catalyst exhibited much higher activity than the amorphous or crystalline analogues; this higher activity originated from the enhanced intrinsic activity of the catalytic sites. These findings open up opportunities to explore nickel(II) borates as a new class of efficient nonprecious metal OER electrocatalysts, and to improve the electrocatalyst performance by modulating their crystallinity.