Sol gel preparation methods for barium strontium titanate based solar devices

Sol gel preparation for Barium Strontium Titanate (BST) is discussed. In this paper, four methods of sol-gel preparation are presented using similar precursors namely, barium acetate (BA), strontium acetate (SA), titanium isopropoxide (TI), 2-methoxyethanol (2M), deionized water (DIW) and acetic acid. Ba0.5Sr0.5TiO3 base is prepared by using simple sol gel process involving weighing, mixing and ultrasonic stirring. In method I, acetic acid is added to the base solution. Method II is similar to method I with extra time allocated for ultrasonic stirring. In method III includes stirring and filtering process. In method IV, deionized water (DIW) and acetic acid are added to the base solution. In Method II and Method III, all chemicals used are stored in open rack in chemical storage. However, in Method I and Method IV the chemicals used are stored in dry cabinet/ glass flask with silica gels. The objective of all these four methods is to mitigate precipitate. The resultant sol gel shows different color according to the methods used. Method I show clear and no precipitate. The resulting sol-gel is spin coated on silicon substrate and annealed at 950 °C for 4 hours. X-ray diffraction (XRD) is used to characterize as-prepared samples. Sample prepared using method I is found to have composition of BST.