Síntese de titanato de bário pelo método Pechini

Abstract

The main characteristics of barium titanate are ferroelectricity, piezoelectricity, and high dielectric constants. Due to these characteristics, there are several applications such as capacitors, electronic devices, power transmission lines, among others. The present work proposes the synthesis of BaTiO3 by the sol-gel route using the Pechini method. For this, titanium propoxide was used as the titanium source, barium chloride as the barium source, citric acid as the chelating compound, and polyethylene glycol (PEG 6000) or Ethylene glycol (EG) as an esterifying agent. To evaluate the effect of the esterifying agent on the synthesis, 17.2 and 4.3 grams of PEG 6000 and 2.7 grams for EG were used. For the synthesized samples, the calcination temperature varied (400, 800, and 1100ºC) as well as the esterification agents. PEG 6000 hindered synthesis because of the smaller amount used, the greater crystallinity was obtained. This was then replaced by the EG which has less molecular weight and obtained better results. The formation of the barium titanate phase was obtained from calcination at 1100ºC with EG.