Effects of cerium oxide doping on microstructure and properties of Ni-GO-CeO2 nanocomposite coatings

Abstract

Ni-GO-CeO2 electrodeposited coatings reinforced with different amounts of CeO2 nanoparticles have been prepared in this work. Influences of cerium oxide doping on surface, structure, chemical composition, crystallite size, surface roughness, corrosion and wear behavior were evaluated to explore the optimal process parameters for co-electrodeposition. The nanocomposite deposits present granular colonies like morphology. The dispersion of graphene oxide (GO) and CeO2 within nickel matrix was confirmed by EDS and XPS observation. The inclusion of CeO2 slightly decreased the crystallite size of Ni matrix. Ni-GO-CeO2 deposited at 5 and 10 g L−1 CeO2 in electrolyte showed surface average roughness (Ra) of 3.4 and 5.0 nm, root mean square roughness (Rq) of 4.5 and 7.3 nm, respectively. It contains 92.68–95.19 wt.% Ni, 4–4.32 wt.% GO, and 0.59–3.32 wt.% CeO2. The CeO2 content enhanced as the CeO2 increased. Ni-GO-CeO2 nanocomposite coating electrodeposited with 10 g/L CeO2 has the lowest icorr of 0.8 × 10−6 A cm−2 and the largest Rp of 49.99 kΩ cm2, respectively, indicating the formation of corrosion resistant coatings with the inclusion of CeO2 particles. Deposits containing more CeO2 could resist performance deterioration for a longer time, exhibiting better electrochemical stability.