International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Index Copernicus Value (2015): 78.96 | Impact Factor (2015): 6.391 Volume 6 Issue 4, April 2017 www.ijsr.net Licensed Under Creative Commons Attribution CC BY Corrosion and Structural studies of Galvanostatically Electrodeposited ZnMgO Thin Films Shraddha Bais 1 , R. K. Pathak 2 Govt. M.L.B. Girls PG college, Indore (M.P.), India, 452001 Abstract: ZnMgO thin films have been grown on Stainless steel substrate by galvanostatic electrodeposition from nitrate baths. The effect of bath composition was observed. A comparative study of corrosion parameters were done in three different electrolytes; NaCl, HCl, H 2 SO 4 by tafel plot. 1-Phenyl-1H-tetrazole-5-thiol was used as inhibitor in deposition bath and its effect on corrosion rate was determined and found effective in corrosion inhibition of ZnMgO thin films. The morphology and structural characterization of thin films were done by Scanning Electron Microscopy (SEM) and X-Ray Diffraction pattern (XRD). Elemental composition has been determined by Energy Dispersive X-Ray spectroscopy (EDAX). XRD confirmed that the films possessed Hexagonal wurtzite structure. Structural changes were also observed by XRD studies which indicate a possibility of partial replacement of Zn atoms by Mg atoms in the lattice structure. Keywords: Galvanostatic, Thin films, corrosion rate, inhibitor, SEM, XRD 1. Introduction ZnO thin films have attracted great research interest in recent years due to its excellent electrical, electronics and optical properties. ZnO is a multifunctional material. It has a wide direct band gap (3.36 eV) and a large excitonic binding energy(60 meV) due to which it is used in many areas like light emitting diode [1] , laser diode [2] , gas sensor [3], [4] and solar cells[5]-[7]. Additional advantage of ZnO is, it is a bio safe and bio compatible material [8], [9]. ZnO thin films are also used in thin film transistors, uv- photodetector [10], wear resistance films [11] etc. Corrosion behaviour of ZnO and their composite films deposited on different substrates like steel, aluminium and brass were studied in different electrolytes [12]-[14]. Depending on the application the properties of ZnO thin films can be altered by alloying with another materials such as Cadmium (Cd), Iron (Fe), Nickel (Ni), Manganese (Mn), Magnesium (Mg) etc Manganese doped ZnO were monitored as dilute magnetic semiconductor (DMS) which exhibit room temperature ferromagnetism [15]. Shanmugans et al [16] prepared Mg doped ZnO nanoparticles to analyse their structural properties. ZnO and MgO has lattice mismatch. ZnO is wurtzite while MgO is cubic but the ionic radii of Magnesium and Zinc are relatively similar so Zn 2+ can be replaced by Mg 2+ [17]. Fe doped ZnO thin films have been fabricated from different fabrication methods and most of the researches mainly focused on their ferromagnetic behaviour [18]-[20]. Structural and optical properties of ZnO thin films and their relative materials were also analysed by researchers [21]-[23]. Various physical and chemical methods have been used for thin film deposition such as Sol-Gel method [24], thermal evaporation [25], Radio frequency(RF) magnetron sputtering [26], Pulse laser deposition [27], Chemical bath deposition [28], electrodeposition [29], [30] etc. Despite the other techniques Electrodeposition is a promising technique for the preparation of alloy thin films from aqueous solution due to its simplicity and cost effectiveness. This technique doesn‟t need vacuum system or toxic gases. Electrodeposition process can be carried out on any conductive substrate like glass, polymers, metals, templates etc. A corrosion inhibitor is a substance when added in a small concentration to an environment reduces the corrosion rate of a metal or alloy exposed to that environment. Organic compounds containing Nitrogen, Oxygen and Sulphur reduces the corrosion rate. Inhibitors act by selectively precipitating on cathodic areas to limit the diffusion of reducing species to the surface. In present work ZnMgO films were electrodeposited from nitrate baths and their corrosion behaviour was tested in presence and absence of 1-Phenyl-1H-tetrazole-5-thiol used as inhibitor. 1-Phenyl-1H-tetrazole-5-thiol 2. Experimental Procedure The composition of electroplating baths used for synthesis of ZnMgO thin films were 0.05 M Zn(NO 3 ) 2 , 0.05-0.20 M Mg(NO 3 ) 2 , 0.01 M NaNO 3 , 0.01 M KCl. All chemicals were of A.R. grade and deposition solutions have been prepared in distilled water. All electrochemical experiments were carried out in a conventional three electrode cell without stirring. All potentials were referred to the saturated calomel electrode (SCE). Stainless steel 202 ( SS 202) plates with surface area 1cm 2 were used as working as well as counter electrode. SS 202 plates were cleaned with emery paper and washed successively with acetone and distilled water. For data Paper ID: ART20172531 1163