Studies on the electrodeposition of chromium and its alloy from Ecofriendly Cr(Iii) Electrolytes and room temperature ionic liquids-Rtil

Abstract

Electrodeposition of chromium and its alloy from eco-friendly Cr(III) electrolyte is an environmentally benign process for both decorative and functional applications. It has been amply demonstrated that electrodeposited Cr by direct current (DCD) and pulse current (PCD) on metal such as mild steel, can provide aesthetic appearance and protection against corrosion. Glycine and dimethylformamide (DMF) used as Crcomplexing agent, pulse and brush electrodeposition techniques have been used to enhance current efficiency and deposit morphology. We obtained current efficiency maximum of 36% using pulsed current which is two times higher than that of reported in literature. Eco-friendly Cr(III) electrolyte with suitable complexing agent is a good candidate to replace toxic Cr(VI) electrolyte. Ionic liquid/deep eutectic solvents have been prepared using choline chloride and ethylene glycol (hydrogen bond donor) for electrodeposition of Fe-Ni-Cr alloy. The influence of electrodeposition potential upon the Fe, Ni, and Cr composition has been investigated. Ionic liquid/deep eutectic solvent provides nanosized metal and alloy with negligible amount of H2 evolution, therefore current efficiency increased. Electrodeposit has been characterized mainly by using XRD, SEM, AFM and EDS techniques. Anticorrosive property has been studied using potentiodynamic polarization and electrochemical impedance spectroscopy.