Bioinfo Publications 87 ZnO AND Zn0.99Co0.01O CRYSTALLITES GROWN USING CHEMICAL METHOD International Journal of Knowledge Engineering ISSN: 0976-5816 & E-ISSN: 0976-5824, Volume 3, Issue 1, 2012, pp.-87-88 Available online at http://www.bioinfo.in/contents.php?id=40 LEENA JOSHI 1 * AND SUNITA KESHRI 2 1 Department of Applied Physics, Priyadarshini College of Engineering, Hingna Road, Nagpur, MS, India. 2 Department of Applied Physics, Birla Institute of Technology, Mesra, Ranchi, Jharkhand, India. *Corresponding Author: Email- leenaljoshi@gmail.com Received: February 28, 2012; Accepted: March 06, 2012 Abstract- Crystallites of ZnO and Zn0.99Co0.01O have been grown on glass substrate by wet chemical decomposition of zinc/cobalt-amino complexes in aqueous medium. Structural properties of grown crystallites were investigated by the help of X-ray Diffractometer, Scanning Electron Microscope and Energy Dispersive X-ray spectroscope. Keywords- Doped ZnO; Different morphologies International Journal of Knowledge Engineering ISSN: 0976-5816 & E-ISSN: 0976-5824, Volume 3, Issue 1, 2012 Introduction During the recent years ZnO has received tremendous attention as photo-catalysts [1], luminescent materials [2], transparent elec- tron conductors [3] and solar cells [4]. In most of these applica- tions, ZnO is doped for enhanced or added functionality. Transi- tion element (Mn, Co, Fe, etc.) doped ZnO is a potential candidate for diluted magnetic semiconductors [5-7], where concentration of charge and spin can be controlled independently by changing the concentrations of dopant elements. Among other oxide-based DMS, ZnO doped with small amount of Co 2+ (i.e. Zn1-xCoxO), with- out any modification in the structure has been considerably ex- plored with abundant theoretical and experimental reports of a possible intrinsic room temperature ferromagnetism [3]. However these results remain still debated as some of the groups have reported about either the absence of ferromagnetism [4] or the presence of segregated Co impurities [5] in these compounds. The previous reports on chemical deposition method of Zn1-xCoxO thin crystallites show that the morphology of the crystallites having rod structure is strongly dependent on the experimental condi- tions, such as solution concentration, pH of the solution, growth temperature and the substrate preparation [8]. Experimental The starting materials to synthesize ZnO and Zn0.99Co0.01O crys- tallites were Zn(NO3)2.H2O, Co(NO3)2.H2O and Hexamethylenetet- ramine (HTMA) which were separately dissolved in water to get 0.1M solution of each. Solutions of Zn(NO3)2.H2O and Co(NO3) 2.H2O were mixed together in the required stoichiometric ratio so as to achieve 1% Co doped ZnO. The solution of HTMA was then mixed with the above solution in the ratio 1:4. The film growth rate was found to be a sensitive function of bath pH as well as temper- ature. The critical range of pH value for good quality crystallites was found to be 10.5-11.0. About 25% ammonia aqueous solution was added to adjust the pH of the solution as about 11. The mix- ture was stirred for about 10 minutes till the transparent solution was obtained. Crystallites of Zinc oxide (ZnO) and Co-doped ZnO have been deposited on glass substrates (micro slides) by wet chemical decomposition of zinc-amino complexes in aqueous medium. The glass substrate was cleaned using ultrasonic clean- er by dipping the substrate in acetone and isopropyl alcohol. The cleaned substrate was tightly held in a holder so that only a requi- site area for crystallite deposition was exposed. Thus, the crystal- lite growth area could be easily varied by adjusting the holder arrangement. The deposited ZnO crystallites were subsequently Citation: Leena Joshi and Sunita Keshri (2012) ZnO and Zn0.99Co0.01O Crystallites Grown Using Chemical Method. International Journal of Knowledge Engineering, ISSN: 0976-5816 & E-ISSN: 0976-5824, Volume 3, Issue 1, pp.-87-88. Copyright: Copyright©2012 Leena Joshi and Sunita Keshri. This is an open-access article distributed under the terms of the Creative Com- mons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.