Surface modification of Mg2Ni alloy in an acid solution of copper sulfate and sulfuric acid

A simple method of electroless copper plating for the surface modification of Mg,Ni alloy has been described in this paper. The plating solution conta ins only copper sulfate and sulfuric acid which are less toxic to the envir onment than the chemical reagents used in conventional copper plating solut ions. Moreover, the coating process was very easy and fast to operate needi ng no special treatment for air-exposed samples before plating. The phase c omposition and microstructure of the modified and unmodified Mg,Ni alloy we re examined by X-ray diffraction (XRD) and scanning electron microscopy (SE M). The electrochemical characteristics and performance of the electrodes w ere examined using galvanostatic charge/discharge and cyclic voltammetry te chniques. A discharge capacity of 210 mA hg(-1) Mg2Ni has been obtained fro m the modified Mg2Ni alloy. The results show that the surface modification of the Mg,Ni alloy electrode can significantly improve its electrochemical characteristics and performance. It is suggested that this copper plating m ethod is very promising for surface modification of the Mg2Ni alloy in hydr ide batteries. (C) 1999 Elsevier Science S.A. All rights reserved.