Electrodeposition Behavior of Polycrystalline Ni–Mo–La Composite in Alkaline Solution

Abstract

The polycrystalline Ni–Mo–La composite coating was obtained by electrodeposition through the addition of La3+ ions into Ni, Mo ions main salt weak alkaline solution. The obtained composite contain 0.92 at.% La. According to the law of ionic activity, the redox reaction of three kinds of metal atoms was studied by polarography and cyclic voltammetry. It was found that the addition of lanthanum ions changed the composite structural, phase, and element, and the OH− ions were deduced during the electrodeposition in alkaline solution. The introduction of lanthanum and molybdenum ions negatively shifted the reduction potential of nickel ions and broadened the peaks significantly in the deposition process, retarding the reduction and deposition rate of Ni ions, which was characterized by a multi-step reduction process of Mo and La metal atoms.