Ni-Al nanocomposite coating electrodeposited from deep eutectic solvent

NiAl nanocomposite coatings are fabricated by pulsed electrodeposition in choline chloride-ethylene glycol (ChCl-EG) deep eutectic solvent (DES) containing Nickel chloride and Al nanoparticles. The dispersion stability of Al nanoparticles in the DES-based colloidal electrolyte is investigated. Meanwhile, the deposition behavior and nucleation growth mode of Ni in the colloidal electrolyte are studied. Moreover, the influences of the Al nanoparticles loading in the DES on the content and distribution of NiAl coating is investigated. When the concentration of Al nanoparticles in the DES is 32 g L−1, the Al content in the composite coating could reach as high as 19.39 wt%. The NiAl nanocomposite coating exhibits superior oxidation resistance to high temperature than the pure Ni coating. Moreover, after high-temperature calcination treatment of the NiAl nanocomposite coating, the obtained Ni-Al + HT coating could form NiAl intermetallic compounds and metal oxides, which performed superior mechanical hardness and anti-corrosion property. •NiAl nanocomposite coatings were firstly fabricated in deep eutectic solvents.•The deposition mechanism of Ni2+ with Al nanoparticles was investigated.•The content of Al nanoparticles incorporated into Ni matrix was up to 19.39 wt%.