Study of nanocrystaline Ni-Welectrodeposition mechanism with EIS thecnique

Nickel-tungsten alloy are known for their excellent corrosion resistance,wear resistance, high hardness and magnetic properties[1,2].it is a well established fact that W cannot be electrodeposited from aqueous electrolytes, but can ba codeposited with iron group metals such as nickel to form an alloy[1,3] . There are a lot of papers dealing with the mechanism of W and Ni codeposition.according to Younes et al [4]. W is electrodeposited from a mixed complex [(Ni)(WO4)2(H)2(Cit)]2-, which forms in the bulk of electrolyte solution. many researchers have synthesized nanocrystallineNi–Walloys for different property evaluation studies [5-7] However,the mechanism alloy electrodeposition has still not been elucidated.The purpose of the present work was to study the electrodeposition mechanism of nickel-tungsten alloys by EIS, clarifying the factors influencing tungsten content and morphology