Electrodeposition of Ni-Cu alloy films from nickel matte in deep eutectic solvent

• Published in: Materials chemistry and physics Vol. 232; pp. 6 - 15
• Main Authors: Rao, Shuaichao, Zou, Xingli, Wang, Shujuan, Lu, Yi, Shi, Tianyu, Hsu, Hsien-Yi, Xu, Qian, Lu, Xionggang
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.06.2019
• Subjects: Deep eutectic solvent; Electrodeposition; Ni-Cu alloy; Nickel matte; Electrodeposition; Deep eutectic solvent; Nickel matte; Ni-Cu alloy
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2019.04.052

Direct electrodeposition of Ni-Cu alloy films from nickel matte precursor in choline chloride (ChCl)/urea (1:2 molar ratio) based deep eutectic solvent (DES) has been investigated. The nickel matte was firstly sintered with KCl at 450 °C for 45 min to form metal chlorides (NiCl2 and CuCl), then the chlorinated nickel matte was dissolved into ChCl/urea DES, which served as electrolyte for the electrodeposition of Ni-Cu alloy films. For comparison, electrodeposition of Ni-Cu alloy films from pure chlorides (NiCl2·6H2O and CuCl) precursors in ChCl/urea DES has also been investigated. Cyclic voltammetry analysis confirms that the two electrodeposition processes in DES are similar, and Ni-Cu alloy films with different compositions can be deposited in a controlled manner. The phase compositions, microstructures and corrosion resistance performances of the two Ni-Cu alloy films electrodeposited from different precursors have also been investigated and compared. It is suggested that the chlorination-electrodeposition process in DES is a promising strategy for the electrochemical extraction of alloys from complex raw materials. [Display omitted] •Ni-Cu alloy films have been directly electrodeposited from nickel matte in deep eutectic solvent for the first time.•The electrodeposition process has been investigated systematically.•The proposed process is a promising strategy for the recovery of metals/alloys from complex raw materials.