Latent heat study of phase transition in Ba0.73Sr0.27TiO3 induced by electric field

We have developed a modified power-compensation DSC to evaluate the electrocaloric properties of ferroelectrics. With this apparatus, latent heat of electric-field-induced phase transition in Bao.73Sro.27TiO3 (BST) ferroelectric ceramics has been investigated in detail. It varies with temperature and reaches its climax at 25DGC, close to the ferroelectric-paraelectric phase transition temperature, when induced by the same electric field of 15 kV cm -1. The theoretical saturated endothermicity induced by enough high electric field at 25DGC is expected to 0.59 J g-1, which is 84% of the total phase transition latent heat of BST. At last the origins of difference between exothermicity and endothermicity are discussed.