Strontium Titanate Powder Preparation
Solvent Vaporization Method:
Freeze Drying Method — In the first stage the stable complex of titanium citrate is prepared by mixing titanium tetra isopropoxide with citric acid and deionzed water at about 70.C. The solution is mixed with ammonia solution by adjusting the ph to 5 to 6. The concentration of titanium is increased by boiling the solution with simultaneously removes the isoporpanol by product.
Strontium nitrate solution is added to the above solution so as to form strontium titanium solution. This solution sprayed into liquid nitrogen as a mist for rapid freezing. Thus freeze drying of the product at -60.C causes the removal of water from the solution by sublimation process.
In the next stage the product formed is heated in a controlled atmosphere a temperature of 700.C for few hours. After heating it generates spherical strontium titanate powder with very high surface area.
To be contd…
