Zinc electroplating from non-cyanide alkaline solution is carried out in the presence of condensation product formed between DL-alanine (DLA) and glutaraldehyde. The bath constituents and bath variables are optimized through standard Hull cell experiments. The current efficiency and the throwing power are measured. High shift of potential towards more cathodic direction was observed in presence of addition agents. Corrosion resistance test reveals good protection of base metal by zinc coating obtained from the developed electrolyte. SEM photomicrographs show fine-grained deposit in the presence of condensation product. IR spectrum of the scraped deposit shows the inclusion of the condensation product in the deposit during plating. The consumption of brightener in the lab-scale is 6 mLL^-1 for 1000 amp-hour.

Zinc electrodeposition from sulphate bath was carried out in presence of condensation product formed between glycyl–glycine (GGL) and furfural (FFL). The bath constituents were optimized through Hull cell experiments. Operating parameters such as pH, temperature and current density were also optimized. Current efficiency and throwing power were measured. Polarization study revealed shift of potential towards negative direction in the presence of addition agents. Corrosion resistance test revealed good protection of base metal by zinc coating obtained from developed electrolyte. SEM photomicrographs showed fine-grained deposit in the presence of condensation product. IR spectrum of the deposit showed inclusion of condensation product in the deposit during plating. The consumption of brightener in the lab scale was 7 mLL^-1 for 1000 amp-h.

Electro-polymerization of orthonitroaniline was carried out on graphite electrode in hydrochloric acid medium. Zinc–nickel alloy deposition was carried out in the presence of polynitroaniline in acid sulphate bath. The bath constituent and bath variables were optimized through Hull cell experiments. The current efficiency and throwing power were measured. High shift of potential towards more cathodic direction was observed in presence of addition agent. Corrosion resistance test revealed good protection of base metal by zinc–nickel coating obtained from the developed electrolyte. SEM photomicrograph shows fine-grained deposit in the presence of addition agent. The consumption of brightener in the lab-scale was 0.01 gL^-1 for 1000 amp-h.

Zinc electrodeposition from sulphate chloride bath was carried out in presence of condensation product formed between chitosan and veratraldehyde. The bath constituents and operating parameters such as pH, temperature and current density were optimized through Hull cell experiments. Current efficiency and throwing power were measured. Polarization study revealed high shift of potential towards negative direction in the presence of addition agents. Corrosion resistance test revealed good protection of base metal by zinc coating obtained from developed electrolyte. SEM photomicrographs showed fine-grained deposit in the presence of condensation product. The IR spectrum of the deposit showed inclusion of the condensation product during electroplating. The consumption of brightener in the lab scale was 5 mLL^-1 for 1000 amp-h.

The influence of a condensation product (CP) of veratraldehyde (VRTD) and 𝑝-amino benzoic acid (PABA) on Zn–Ni alloy electrodeposited onto mild steel was studied in acidic sulphate solutions. Ethylenediaminetetraaceticacid (EDTA) and cetyltrimethylammoniumbromide (CTAB) were used as complexing and wetting agents, respectively. The effect of bath constituents, pH, current density and temperature on nature of deposit were studied through Hull cell experiments. The bath constituents and operating parameters were optimized. Deposit properties and corrosion resistance were discussed. Throwing power, current efficiency and polarization studies were carried out. SEM photomicrographs of the deposit obtained from optimum bath revealed fine-grained deposit of the alloy in the presence of condensation product and hence modified the morphology of zinc–nickel alloy deposit. IR spectrum of the scrapped deposit showed inclusion of addition agent.

Electrodeposition of zinc on steel was obtained from acid chloride bath containing condensation products (CP) of 3,4,5-trimethoxy benzaldehyde (TMB) and chitosan (CTN). The effect of bath constituents, pH, current density and temperature on the nature of deposit was studied by Hull cell experiments. The bath composition and operating parameters were optimized. The adhesion, ductility and corrosion resistance of the deposits were discussed. Throwing power and current efficiency values under different plating conditions were measured. SEM photomicrographs of the deposit were taken to study the surface morphology. The inclusion of addition agent in the deposit was investigated from IR spectrum of the scrapped deposit. The consumption of brightener in the lab scale is 10 mLL^-1 for 1000 amp-h.

The surface treatment of zinc and its corrosion inhibition was studied using a product (BTSC) formed in the reaction between benzaldehyde and thiosemicarbozide. The corrosion behaviour of chemically treated zinc surface was investigated in aqueous chloride–sulphate medium using galvanostatic polarization technique. Zinc samples treated in BTSC solution exhibited good corrosion resistance. The measured electrochemical data indicated a basic modification of the cathode reaction during corrosion of treated zinc. The corrosion protection may be explained on the basis of adsorption and formation of BTSC film on zinc surface. The film was binding strongly to the metal surface through nitrogen and sulphur atoms of the product. The formation of film on the zinc surface was established by surface analysis techniques such as scanning electron microscopy (SEM–EDS) and Fourier transform infrared spectroscopy (FTIR).

The corrosion inhibition characteristics of acetyl coumarine (AC), bromo acetyl coumarine (BAC) and thiazole derivatives (BTMQ and BTCQ) on the corrosion of zinc in 0.1 M HCl solution were investigated by weight loss, potentiodynamic polarization and impedance techniques. The inhibition efficiency increased with increase in inhibitor concentration upto 5 × 10^-4 M, then gave almost same inhibition efficiency. The polarizationmeasurements indicated the mixed nature of inhibitors. The adsorption of compounds obeyed Langmuir’s adsorption isotherm. The thermodynamic functions for adsorption processes were evaluated.

The bright ZnNi alloy coating on steel surface was prepared by elctrodepostion technique using brightener ethyl vanillin (EV). To know the influence of brightener on deposition and dissolution behaviour of ZnNi alloy, cyclic voltammetric studies were carried out. FT–IR spectroscopic evidence was given to confirm selective adsorption of brightener on steel surface. The brightener enhances current efficiency and throwing power of plating bath during coating. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses in presence of brightener confirmed the change in surface morphology, phase composition and preferred orientation of ZnNi coating. In presence of brightener, nickel content of the coating was reduced at higher current density and thickness. In addition, deposit properties like appearances, hardness, adherence, ductility and corrosion resistance of ZnNi alloy deposits were also improved in bright deposit. Simultaneously, effect of deposition current density and thickness on corrosion behaviour of coating was examined.