A study on Nickel plating onto Stanum oxide by electroless plating method

Abstract

Currently, stanum oxide (SnO) materials are vigorously investigated due to its potential electronic properties. In most cases SnO layers synthesized by a typical potentiostatic anodization exhibit a characteristic stacked internal structure with a lot of cracks and micron sized transversal pores and channels, thus can significantly affect the properties of oxide layers (e.g., electronic conductivity). In order to improve surface integrity, the SnO were nickel coated via electroless coating process. This research focused on the best nickel concentration in the electroless bath, molar ratio of reducing agent used (hypophosphite), and characterized it using SEM/EDX, XRD and AAS. SnO powders were pre-cleaning using ultrasonic cleaner with acetone. The electroless nickel plating were conducted by varying nickel content in the electroless bath with 10%, 20% and 50%, whilst the molar ratio of reducing agent were 1:1 and 1:3. Based on results of SEM/EDX, the SnO powders were completely coated using 50% nickel content and molar ratio 1:3 of reducing agent. XRD analysis shows the nickel phase presented in the SnO powders and crystallite size were increase with increasing nickel content and using molar ratio 1:3 reducing agent. The solution of the electroless bath were taken out to characterize using AAS to measure the nickel concentration throughout electroless process. Nickel concentration decreased over time indicating the nickel ion have been reduced to SnO powders.