Effects of Heat Treatment Temperature on the Morphology, Composition, and Electrocatalytic Properties of Electrodeposited NiB Thin Films Towards OER

•Defects associated with oxygen vacancies were formed during the electrodeposition of NiB films.•NiB thin film without heat treatment present efficiencies similar or superior to other catalysts commonly used for OER.•The thermal treatment of NiB films promotes the formation of multiple phases (Ni2B, Ni3B and NiO) on the surface.•The number of oxygen vacancies formed in NiB films decreased with heat treatment.•The efficiency of NiB catalysts decreases with increasing heat treatment temperature.