Relaxor behavior in Y_2/3Cu₃Ti₄O₁₂ ceramic

Yttrium copper titanate (Y_2/3Cu₃Ti₄O₁₂) (YCTO) nanoceramic was fabricated by the semiwet route using metal nitrate solutions and powder of TiO₂ in stoichiometric ratio. The dielectric and ferroelectric properties of YCTO were investigated within the temperature range of 308–500 K and frequency range of 2 Hz–5 MHz. A characteristic dielectric anomaly was observed from 350 to 425 K. YCTO exhibited a broad dielectric peak which got suppressed and shifted to higher frequency region with increasing temperature. The low temperature frequency dispersion may be assigned to the slowing down of dipolar fluctuations within the polar nanoclusters of YCTO. This dielectric anomaly can be assigned to a relaxor ferroelectric behavior. Such broad dielectric peak in the ε ′–T plot can be well fitted by a modified Curie–Weiss law. Additionally, the presence of a broad maximum in the ε ″–log f plot or tan δ–log f plot and a slim polarization–electric field (P–E) hysteresis loop also suggests the existence of a relaxor ferroelectric behavior in the ceramics.