ISSN: 0973-4945; CODEN ECJHAO E-Journal of Chemistry http://www.e-journals.net 2010, 7(3), 894-898 Template-Assisted Sol-Gel Synthesis of Nanocrystalline BaTiO 3 T.V. ANURADHA Department of Materials Engineering, Indian Institute of Science, Bangalore – 560 012, India. [email protected]Received 28 October 2009; Accepted 20 December 2009 Abstract: Nanocrystalline perovskite barium titanate with an average particle size less than ~10 nm is produced using sol-gel route involving ligand-assisted templating. BaTiO 3 is obtained by the controlled hydrolysis and condensation reaction of barium acetate (Ba(CH 3 COO) 2 ) with titanium tetra chloride (TiCl 4 ) in the reverse micelles of dodecylamine (DDA) which is used as the template. Our attempts to produce mesoporous BaTiO 3 have resulted in the formation of nanocrystalline BaTiO 3 . The synthesis of nanostructured BaTiO 3 is carried out using the ligand-assisted templating approach which proceeds through the sol-gel route. Dodecylamine is used as the template. The sol-gel process in general presents inherent advantages because the nanostructure of the desired materials can be controlled together with their porous structure. Ligand-assisted templating approach involves the formation of covalent bond between the inorganic analogue and the template. Ba(CH 3 COO) 2 and TiCl 4 are used as barium-source and titanium-source respectively. The reaction between Ba(CH 3 COO) 2 and TiCl 4 is found to take place deliberately on the pre- assembled species which acts as the template or occurring with in them which in turn will lead to the generation of the desired nanoscale structure (nanopores or nanoparticles). Keywords: Ligand-assisted templating; Ba(CH 3 COO) 2 , TiCl 4 , Dodecylamine; XRD, TEM. Introduction Barium titanate (BaTiO 3 ) is well-known for its high dielectric constant. The dielectric properties are controlled by purity and microstructure which in turn are dependent on the method of preparation 1 . Recent advances in nanotechnology such as: Multilayer capacitor, Micro Electro Mechanical Systems and Dynamic Random Access Memories have resulted in the miniaturization of devices 2 . These require nanosize BaTiO 3 . Various chemical routes like coprecipitation 3 , sol-gel 4 , hydrothermal 5-6 and solution combustion 7 are known to yield
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ISSN: 0973-4945; CODEN ECJHAO
E-Journal of Chemistry
http://www.e-journals.net 2010, 7(3), 894-898
Template-Assisted Sol-Gel Synthesis of
Nanocrystalline BaTiO3
T.V. ANURADHA
Department of Materials Engineering,
Indian Institute of Science, Bangalore – 560 012, India.