Synthesis and Characterization of Monolithic ZnO-SiO2 Nanocomposite Xerogels

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Mechanics, Materials Science & Engineering, July 2017 – ISSN 2412-5954

Synthesis and Characterization of Monolithic ZnO-SiO2 Nanocomposite Xerogels 1

D. Prasanna1, P. Elangovan1,a, R. Sheelarani1 1 – Dept. of Physics, Pachaiyappa’s College, Chennai, Tamil Nadu, India a – drelangovanphysics@gmail.com DOI 10.2412/mmse.57.4.239 provided by Seo4U.link

Keywords: nano composites xerogel, sol gel method.

ABSTRACT. Synthesis and characterization of ZnO doped SiO2 monolithic nano composite xerogels were prepared by using sol-gel method. In this method prepared samples were observed, that an ageing period of two days is optimum and a very slow controlled evaporation rate is followed for few days. The prepared ZnO-SiO2 monolithic nano composite xerogels for various concentrations are characterized by X-ray diffraction, field-emission scanning electron microscope and Fourier transform-infrared spectroscopy methods.

Introduction: ZnO nano particle embedded into SiO2 composites have attracted extensive research interests. It has been found that these materials have improved luminescence efficiency compared to bulk ZnO material. Excellent non-linear optical properties, saturable absorption and optical bistability have also been reported for these composites various techniques have been employed to prepare nano ZnO-SiO2 composites, including sol-gel impregnation and magnetron sputtering, etc. Wide varieties of glass, glass-ceramic monolithics, nanostructural powders etc., are synthesized through sol-gel technique. In the present work ZnO embedded into SiO2 nanocomposites are synthesized through the sol-gel process. The steps needed for producing monolithic xerogels are carefully followed. Experimental. Materials. Zinc acetate dihydrate (Zn (CH3COO)22H2O), Triethanolamine (TEA) and Sodium hydroxide (NaOH), Ethanol(C2H6O), Tetraethyl orthosilicate (TEOS) were purchased from s d finechem. limited in Chennai. Analyses. The starting solution is prepared by mixing TEOS, ethanol and water in the ratio of 10:10:14 respectively. The starting solution is stirred at 40C for few minutes. One drop of concentrated HCl is diluted in 3 ml of deionized water, is added drop wise in the starting solution. SAfter 1 hr. of stirring 4 drops of diluted ammonia solution is added to maintain the pH at 4. The second solution is prepared using 200 g of Zn(CH3COO)22H2O dissolved in deionized water. This solution is stirred for 1½ hrs. at 50C. Finally, the starting and second solutions are mixed and stirred for 1½ hrs. The final sol is poured into the plastic mould and covered with aluminium foil. The sols are aged at 40C for 48 hrs. After 2 days, few holes are made in the aluminium foil and kept at 40C for 2-7 days in drying oven. The number of holes are gradually increased thereafter, and dried for another 10 or 15 days. The samples are heat treated in PID controlled furnace, with the following scheme of heat treatment.

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© 2017 The Authors. Published by Magnolithe GmbH. This is an open access article under the CC BY-NC-ND license http://creativecommons.org/licenses/by-nc-nd/4.0/

MMSE Journal. Open Access www.mmse.xyz


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