Volume : 4, Issue : 3, March - 2015

Sol-Gel Derived Barium Strontium Zirconate Titanate (Ba0.8Sr0.2)(Zr0.2Ti0.8)O3 Powder and Ceramics

Manisha Chawla, Monika Rawat, Seema Rawat, M. Fahim

Abstract :

<p>&lt;p&gt;&amp;lt;p&amp;gt;&amp;amp;lt;p&amp;amp;gt;&amp;amp;amp;nbsp;Barium strontium zirconate titanate (Ba0.8Sr0.2)(Zr0.2Ti0.8)O3 [(Ba+Sr):(Zr+Ti) = 1:1] powder and ceramics were&amp;amp;amp;nbsp;&amp;amp;lt;/p&amp;amp;gt; &amp;amp;lt;div&amp;amp;gt;prepared using a sol&amp;amp;amp;ndash;gel chemical route. BSZT ceramics prepared from the sol&amp;amp;amp;ndash;gel derived powder were characterized for&amp;amp;amp;nbsp;&amp;amp;lt;/div&amp;amp;gt; &amp;amp;lt;div&amp;amp;gt;their structural, morphological, dielectric and ferroelectric properties. Temperature and frequency dependent dielectric&amp;amp;amp;nbsp;&amp;amp;lt;/div&amp;amp;gt; &amp;amp;lt;div&amp;amp;gt;properties were measured for these ceramics in the temperature range 30 to 200oC and at different frequencies of 100 Hz, 120 Hz, 1 kHz, 10 kHz,&amp;amp;amp;nbsp;&amp;amp;lt;/div&amp;amp;gt; &amp;amp;lt;div&amp;amp;gt;20 kHz and 100 kHz. It was observed that ferroelectric to paraelectric transition temperature (Tc) reduced from ~120oC for pure Barium titanate&amp;amp;amp;nbsp;&amp;amp;lt;/div&amp;amp;gt; &amp;amp;lt;div&amp;amp;gt;(BaTiO3) to around 20&amp;amp;amp;ndash;30oC with the addition of strontium. Furthermore the addition of zirconium helped in increasing the dielectric constant&amp;amp;amp;nbsp;&amp;amp;lt;/div&amp;amp;gt; &amp;amp;lt;div&amp;amp;gt;at all frequencies. A well defined ferroelectric loop was observed for the ceramic. Remanent polarization (Pr) value of 0.5121&amp;amp;amp;micro;C/m2 was obtained&amp;amp;amp;nbsp;&amp;amp;lt;/div&amp;amp;gt; &amp;amp;lt;div&amp;amp;gt;for the sample at room temperature.&amp;amp;lt;/div&amp;amp;gt;&amp;lt;/p&amp;gt;&lt;/p&gt;</p>