Electrodeposition of Ni–W alloy corrosion-resistant coating from choline chloride-urea: Experimental Investigations and DFT calculations

NiW alloy is a potential and economical corrosion-resistant material, however, hydrogen evolution and its negative effects are still not satisfactory when co-electrodeposition in an aqueous electrolyte. The purpose of this work was to create a uniform NiW coating by electroplating with a non-toxic solution of choline chloride-Urea eutectic (1ChCl:2Urea). Based on theoretical calculations and experimental results, it has been demonstrated that the 1ChCl:2Urea electrolyte exhibits a higher binding energy and stability, which limits the evolution of hydrogen on the electrode surface. A 3.5% NaCl solution was used to investigate the corrosion resistance of NiW alloys by Tafel polarization and electrochemical impedance spectroscopy. As a result of the improved uniformity of the coating prepared by the ionic liquid electrolyte, the NiW alloy coating exhibits excellent corrosion resistance. The results are beneficial to improve the NiW alloy co-deposition process to prepare a high-performance NiW alloy coating. By extending the application scope of green solvents to corrosion-resistant coatings, this study offers a green solution to the issue.