Effect of duty cycle on NiMo alloys prepared by pulsed electrodeposition for hydrogen evolution reaction

•Morphology and Mo content was affected by varying the duty cycle between 70% and 30%.•The Mo content grows up from 6.6 to 12.7 at% Mo at duty cycle 70% and 30%.•Evidence of the presence of NiMo, NiO, and MoO3 species is found in the XPS analysis.•A remarkable increment of the exchange current when increasing the Mo content.•NiMo alloys analyzed showed activation to HER after aging, particularly the NiMo30%