Journal of the American Ceramic Society, Vol.95, No.1, 296-302, 2012
Bismuth Zinc Niobate Pyrochlore, a Relaxor-Like Non-Ferroelectric
Fixed frequency plots of e' and tan similar to d versus temperature for (Bi1.5Zn0.5)(Zn0.5Nb1.5)O7 (BZN) ceramics with the pyrochlore structure show relaxor-like response below similar to 180 similar to K with frequency-independent permittivity of similar to 130 above similar to 180 similar to K and over the frequency range of 103106 similar to Hz. Impedance data in the range, 10180 similar to K fit an equivalent circuit derived from the classic dielectric relaxation circuit in which the relaxation resistance is replaced by a constant phase element (CPE). Temperature dependence of the circuit parameters shows that BZN is not ferroelectric; the CPE, which is responsible for the relaxor-like behavior, gradually changes from primarily capacitive to primarily resistive with increasing temperature.