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Highly crystallized mullite has been achieved at temperatures of 1100 ℃ and 1400 ℃ by sol–gel technique in presence of titanium and strontium ions of different concentrations: G0 = 0 M, G1 = 0.002 M, G2 = 0.01 M, G3 = 0.02 M, G4 = 0.1 M, G5 = 0.2 M and G6 = 0.5 M. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), LCR meter characterized the samples. Mullite formation was found to depend on the concentration of the ions. The dielectric properties (dielectric constant, loss tangent and AC conductivity) of the composites have been measured, and their variation with increasing frequency and concentration of the doped metals was investigated. All the experiments were performed at room temperature. The composites showed maximum dielectric constants of 24.42 and 37.6 at 1400 ℃ of 0.01 M concentration for titanium and strontium ions at 2 MHz, respectively. Due to the perfect nature of the doped mullite, it can be used for the fabrication of high charge storing capacitors and also as ceramic capacitors in the pico range.


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Abrupt change of dielectric properties in mullite due to titanium and strontium incorporation by sol–gel method

Show Author's information Biplab Kumar PAULKumaresh HALDARDebasis ROYBiswajoy BAGCHIAlakananda BHATTACHARYASukhen DAS( )
Physics Department, Jadavpur University, Kolkata-700 032, India

Abstract

Highly crystallized mullite has been achieved at temperatures of 1100 ℃ and 1400 ℃ by sol–gel technique in presence of titanium and strontium ions of different concentrations: G0 = 0 M, G1 = 0.002 M, G2 = 0.01 M, G3 = 0.02 M, G4 = 0.1 M, G5 = 0.2 M and G6 = 0.5 M. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), LCR meter characterized the samples. Mullite formation was found to depend on the concentration of the ions. The dielectric properties (dielectric constant, loss tangent and AC conductivity) of the composites have been measured, and their variation with increasing frequency and concentration of the doped metals was investigated. All the experiments were performed at room temperature. The composites showed maximum dielectric constants of 24.42 and 37.6 at 1400 ℃ of 0.01 M concentration for titanium and strontium ions at 2 MHz, respectively. Due to the perfect nature of the doped mullite, it can be used for the fabrication of high charge storing capacitors and also as ceramic capacitors in the pico range.

Keywords: mullite, dielectric properties, X-ray diffraction (XRD), sol–gel technique, field emission scanning electron microscopy (FESEM)

References(25)

[1]
Maex K, Baklanov MR, Shamiryan D, et al. Low dielectric constant materials for microelectronics. J Appl Phys 2003, 93:8793.
[2]
Ebadzadeh T, Lee WE. Processing–microstructure-property relations in mullite–cordierite composites. J Eur Ceram Soc 1998, 18:837-848.
[3]
Kurihara T, Horiuchi M, Takeuchi Y, et al. Mullite ceramic substrate for thin film application. Proceedings of the 40th Electronic Components and Technology Conference, Las Vegas, NV, 1990: 68–75.
[4]
Ramakrishnan V, Goo E, Roldan JM, et al. Microstructure of mullite ceramics used for substrate and packaging applications. J Mater Sci 1992, 27:6127-6130.
[5]
Viswabaskaran V, Gnanam FD, Balasubramanian M. Mullite from clay–reactive alumina for insulating substrate application. Appl Clay Sci 2004, 25:29-35.
[6]
Camerucci MA, Urretavizcaya G, Castro MS, et al. Electrical properties and thermal expansion of cordierite and cordierite–mullite materials. J Eur Ceram Soc 2001, 21:2917-2923.
[7]
Kanka B, Schneider H. Sintering mechanisms and microstructural development of coprecipitated mullite. J Mater Sci 1994, 29:1239-1249.
[8]
Sanad MMS, Rashad MM, Abdel-Aal EA, et al. Synthesis and characterization of nanocrystalline mullite powders at low annealing temperature using a new technique. J Eur Ceram Soc 2012, 32:4249-4255.
[9]
Esharghawi A, Penot C, Nardou F. Contribution to porous mullite synthesis from clays by adding Al and Mg powders. J Eur Ceram Soc 2009, 29:31-38.
[10]
Sanad MMS, Rashad MM, Abdel-Aal EA, et al. Effect of Y3+, Gd3+ and La3+ dopant ions on structural, optical and electrical properties of o-mullite nanoparticles. J Rare Earth 2014, 32:37-42.
[11]
Sanad MMS, Rashad MM, Abdel-Aal EA, et al. Mechanical, morphological and dielectric properties of sintered mullite ceramics at two different heating rates prepared from alkaline monophasic salts. Ceram Int 2013, 39:1547-1554.
[12]
Roy DS, Bagchi BJ, Bhattacharya AN, et al. A comparative study of densification of sol–gel-derived nano-mullite due to the influence of iron, nickel and copper ions. Int J Appl Ceram Tec 2013, .
[13]
Roy DS, Bagchi BJ, Das SK, et al. Electrical and dielectric properties of sol–gel derived mullite doped with transition metals. Mater Chem Phys 2013, 138:375-383.
[14]
Sanad MMS, Rashad MM, Abdel-Aal EA, et al. Optical and electrical properties of Y3+ ion substituted orthorhombic mullite Y(x)Al(6−x)Si2O13 nanoparticles. J Mater Sci: Mater Electron 2014, 25:2487-2493.
[15]
Archana J, Navaneethan M, Hayakawa Y. Hydrothermal growth of monodispersed rutile TiO2 nanorods and functional propertie. Mater Lett 2013, 98:38-41.
[16]
Misevicius M, Scit O, Grigoraviciute-Puroniene I, et al. Sol–gel synthesis and investigation of un-doped and Ce-doped strontium aluminates. Ceram Int 2012, 38:5915-5924.
[17]
Sanad MMS, Rashad MM, Abdel-Aal EA, et al. Effect of Gd3+ ion insertion on the crystal structure, photoluminescence, and dielectric properties of o-mullite nanoparticles. J Electron Mater 2014, 43:3559-3566.
[18]
Patil DR, Lokare SA, Devan RS, et al. Studies on electrical and dielectric properties of Ba1−xSrxTiO3. Mater Chem Phys 2007, 104:254-257.
[19]
See A, Hassan J, Hashim M, et al. Dielectric variations of barium titanate additions on mullite-kaolinite sample. Solid State Sci Tech 2008, 16:197-204.
[20]
Ravinder D, Mohan GR, Prankishan, et al. High frequency dielectric behavior of aluminum-substituted lithium ferrites. Mater Lett 2000, 44:256-260.
[21]
Chakraborty AK. Role of hydrolysis water–alcohol mixture on mullitization of Al2O3–SiO2 monophasic gels. J Mater Sci 1994, 29:6131-6138.
[22]
Chakraborty AK. Effect of pH on 980 ℃ spinel phase-mullite formation of Al2O3–SiO2 gels. J Mater Sci 1994, 29:1558-1568.
[23]
Zhang Y, Wu Z, Wang S, et al. Density of Li2TiO3 solid tritium breeding ceramic pebbles. Adv Mat Res 2011, 177:310-313.
[24]
Oréfice RL, Vasconcelos WL. Sol–gel transition and structural evolution on multicomponent gels derived from the alumina–silica system. J Sol–Gel Sci Technol 1997, 9:239-249.
[25]
Roy DS, Bagchi BJ, Das SK, et al. Dielectric and magnetic properties of sol–gel derived mullite–iron nanocomposite. J Electroceram 2012, 28:261-267.
Publication history
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Publication history

Received: 24 March 2014
Revised: 16 June 2014
Accepted: 06 July 2014
Published: 30 November 2014
Issue date: December 2014

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© The author(s) 2014

Acknowledgements

We are grateful to DST and UGC (PURSE program), Government of India, for the financial assistance.

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Open Access: This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.

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