IJIRST –International Journal for Innovative Research in Science & Technology| Volume 1 | Issue 12 | May 2015 ISSN (online): 2349-6010 All rights reserved by www.ijirst.org 517 Structural, Compositional, Morphological, and Optical Properties of Electrodeposited Nanocrystalline ZnO Thin Film Shashikant Rajpal S.R Kumar Department of Applied Sciences and Humanities Department of Applied Sciences and Humanities National Institute of Foundry and Forge Technology, Ranchi, Jharkhand, India National Institute of Foundry and Forge Technology, Ranchi, Jharkhand, India Abstract ZnO is a wide band-gap (3.37 eV) II–VI compound semiconductor with hexagonal wurtzite structure. These films were deposited by electrodeposition technique, containing very low concentrations of sodium citrate and 30% hydrogen peroxide. Ammonium hydroxide is added to control the reaction. The structural, compositional, Surface morphology and optical analysis were studied by X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDS), Scanning Electron Microscope (SEM), and Atomic Force Microscopy (AFM).The hexagonal structure of ZnO (101) is observed with average grain size 48nm. The average RMS surface roughness of the film is observed to be 328.621nm. The bandgap of the ZnO film is observed to be 3.35 eV. The strong peak of ZnO at 381 nm is observed in photoluminescence spectroscopy. Keywords: Zinc Oxide, Thin Film, Electrodeposition, Characterization etc _______________________________________________________________________________________________________ I. INTRODUCTION ZnO is a n-type semiconductor with wide bandgap whose energy lies typically between 3.1 and 3.4 eV at room temperature[1]. ZnO is an important semiconductor material with a large bandgap (3.37 eV) [2], which continues to attract attention because of its low toxicity and its many applications[3]. According to its physical and chemical properties, ZnO can be used as a thin film or as a bulk material[4]. In recent years ZnO is attracting attention for its application in UV lightemitters[5], varistors [6], transparent high power electronics[7], surface acoustic wave devices [8], piezoelectric transducers [9] gas-sensing [10] and as a window material for display and solar cells [11]. ZnO thin films can be deposited by both physical and chemical methods. Physical method includes sputtering [12], pulsed laser deposition [13], Molecular beam epitaxy [14], RF magnetron sputtering [15], and chemical method includes chemical bath deposition [16] Sol–gel [17] electrodeposition [18-21] Among these preparation methods, electrodeposition is widely used in order to obtain oxide materials with specific chemical and physical properties. Choosing an electrodeposition strategy for oxide film formation offers several advantages in comparison with other deposition techniques [22]. Electrodeposition produces denser films with lower resistivity, due to required material continuity for charge transfer [23]. In this paper, we report on the synthesis of nano- structural ZnO grown via electrodeposition method. The morphology and structure characterizations of the ZnO thin films were analysed in detail using X-ray diffraction (X’Pert PRO, PANalytical B.V., PW3040/60, Netherlands), scanning electron microscopy (JEOL JSM 6480 LV, Japan) equipped with Energy dispersive Xray spectroscopy EDS and Atomic Force Microscopy (Nano Surf EZ2, AFM Instrument,Switzerland). Photoluminescene (shimadzu RF-5301PC, Japan) and UV Visible Spectroscopy (Lambda-25Perkin Elmer; USA) measurements were performed on electrodeposited ZnO thin film for optical property examination. II. EXPERIMENTAL The ZnO thin films were deposited from a solution of analytical grade sodium citrate and 30% hydrogen peroxide in an alkaline solution of ammonia and distilled water. Commercial Zinc plates used as substrates, were cleaned in ethanol ultrasonically. The zinc plates were kept vertically in a closed beaker. We prepared different types of samples by varying the times and concentration of the dipping solution. The electrodeposition is carried out using zinc plate as anode and cathode. 40 ml of distilled water was taken in a beaker. In that 0.1M of AR grade sodium citrate and 30% hydrogen peroxide were introduced. The pH of the electrolyte was maintained at 9.5 to 10 by introducing AR grade of ammonia solution. The electrolyte was stirred moderately using magnetic stirrer. The bath was maintained at room temperature. The two zinc plates were put in the electrolyte in a parallel configuration with an interelectrode srperation of 1 cm. The deposition was carried out catholically at -0.4 V at room temperature. The duration of the deposits was 15 minutes. The asdeposited films were whitish grey in colour. After the deposition is completed the substrate was removed from the electrolyte and washed with distilled water.