Synthesis and Characterization of BST Ceramics by Solution Combustion Technique

Abstract

Barium Strontium Titanate (Ba0.6Sr0.4TiO3) has been prepared and characterized in this present study. Phase pure BST powder has been prepared following combustion synthesis technique. Citric acid, ethylene glycol and glycine have been used as a fuel in this combustion process. Different process parameters mainly additional NH4NO3, citric acid as fuel amount, additional chelating agent EDTA and pH of the precursor solution has been optimized with an aim to achieve phase pure BST at a low temperature. Effect of mixed fuel i.e. citric acid + ethylene glycol and citric acid + glycine, has also been studied as a function of powder morphology of BST powder. The optimum precursor combination Metal: Citric Acid: Ammonium Nitrate: EDTA are: 1:1.5:12:0.1 at pH of the precursor solution 7, has been found to yield phase pure BST powder at 800oC. The densification behavior and densification kinetics of the BST powder has also been studied. Powder morphology and microstructure of sintered BST samples was found to depend strongly on the fuel used for combustion. Dielectric behavior of BST samples has also been studied as a function of fuel used.