Role of triethanolamine and furfuraldehyde on the electrochemical deposition and dissolution behaviour of zinc

摘要

The search for the development of non-cyanide zinc plating baths resulted in identification of newer complexing ligands.The deposition and dissolution of zinc was studied by cyclic voltammetric studies using a bath composition consisted of 0.12M Zinc oxide,2.75M sodium hydroxide and required quantity of triethanolamine and furfuraldehyde.Glassy carbon (GC),Platinum and SCE were used as working electrode,counter electrode and reference electrode respectively.The studies were made at different concentrations of the above additives at various scan rates at 30 deg C.The pH of the bath was maintained at 11.5 to 12.0.The deposition of zinc from zincate solutions undergoes successive reduction to zinc.The chemical step followed by first electron transfer is the slow step.Triethanolamine and furfuraldehyde were found to participate in the electron transfer process.Detailed mechanism of deposition and dissolution in presence of triethanolamine and furfuraldehyde are discussed.