Shearing Plate Optical (original) (raw)

Dielectric Properties of Ceramic, CaCu3Ti4O12, Substituted with Sr or Ba

2007

There has been a considerable interest in non-ferroelectric perovskite oxide CaCu 3 Ti 4 O 12 (CCTO). This material was discovered to possess one of the largest static dielectric constants, reaching nearly ε ~ 80, 000 for single-crystal samples at room temperature. This compound has centrosymmetric structure at room temperature with cubic space group Im3. Because of such incredibly high dielectric constant, the structure, dielectric and electrical properties of CaCu 3 Ti 4 O 12 substituted at Ca-site with other alkaline earth metals i.e. Ba and Sr as substitution elements were studied. An extensive studies were carried out on the dielectric properties of the Ca 1-x Ba x Cu 3 Ti 4 O 12 and Ca 1-x Sr x Cu 3 Ti 4 O 12 where x = 0.5, 0.52, 0.56 and 0.6 at various temperatures. The substitutions were based on ionic radius (r Ca < r Sr < r Ba) and the dielectric studies of Ca 1-x M x Cu 3 Ti 4 O 12 (where M = Sr, Ba) have not been reported so far.