Dielectric Properties of Bi4(Ti,Nb,Mn)3O12 Titanates

The (x = 0.05, 0.10, 0.15) solid solutions have been synthesized by means of solid state reactions method, their crystal structure, microstructure, electrical and dielectric properties within wide interval of temperatures and frequencies have been investigated. It is found that the titanates crystallize in an orthorhombic structure and are p-type semiconductors, which sinterability and dielectric constant increase, but grain size and thermo-EMF coefficients decrease at partial substitution of titanium by niobium and manganese. It is established that ceramics is electrically homogeneous and relaxation processes in it are non-Debye-like, and values of activation energy of relaxation obtained from results of impedance and modulus spectroscopy are in a good agreement.