Electrodeposition of cobalt-yttrium hydroxide/oxide nanocomposite films from particle-free aqueous baths containing chloride salts

► Nanocomposite films made of metallic cobalt and yttrium hydroxide/oxide phases are obtained by electrodeposition from particle-free aqueous solutions. ► Effective incorporation of yttrium compounds (ranging from 1 to 30 wt% Y) in the cobalt matrix is achieved using pulse deposition at high cathodic pulses. ► The composites exhibited a partially amorphous/nanocrystalline character. ► Nanoindentation tests revealed that film hardness increased with the incorporation of Y(OH)3/Y2O3 compounds.