Relaxation behaviour of Pb(Ni_1/3Nb_2/3)O₃ ceramics

Abstract

Polycrystalline samples of a cubic perovskite structure with an estimated 2.9% of a minor pyrochlore phase of Pb(Ni1/3,Nb2/3)O3 were synthesized by a high-temperature solid-state reaction technique. Dielectric studies show that the material is a good relaxor with a high dielectric constant. Diffuse phase transition through a wide Curie-temperature range was observed. The activation energy in a specified range of temperature for the material is estimated.

Effect of Nickel Niobate B-Site Precursors on Phase Formation, Microstructure and Dielectric Properties of Perovskite PNN Ceramics

“…It should also be noticed that the difference in the diffusion exponent γ between the PNN ceramics obtained in this present work and those reported earlier 3,7,9,24 could be attributed to the inclusion of secondary phases, which also cause the deterioration in dielectric properties and shift in dielectric maximum temperature (T max ) in previous investigations. 23,24 Furthermore, for a perovskite ferroelectric, it can be established that the diffusion could be caused by grain-size dependence. 2,21 Therefore, this effect can partly be the cause of the increase of diffusion exponent in columbiteroute PNN ceramic.…”

“…The secondary phase is usually a non-ferroelectric compound so it can definitely destroy the overall dielectric properties and act like a pore in some sense for ferroelectric materials. 23,24 Unlike the normal ferroelectrics, the dielectric behavior of PNN ceramics cannot be described by the Curie-Weiss law. Their behaviors tally well with the law 1/ε ∝ (T − T max ).…”

Glass like behaviour in Pb(Mg1/4Cd1/12Nb2/3)O3 relaxor

“…Since the discovery of PMN, numerous pure and modified PMN and its isomorphous compounds have been investigated. Some of them are technologically important [4][5][6][7][8][9][10][11][12][13]. Promising electrical properties of these materials have given a tremendous boost to carry out the fundamental and applied research on relaxor ferroelectrics.…”

Preparation of Lead Zirconate-Lead Nickel Niobate Ceramics by the Reaction Sintering Process

“…It exhibits a diffuse phase transition of around −120 • C, with a much lower peak permittivity of about 4,000 [4]. The crystal structure of PNN at room temperature is cubic (Pm3m) [5]. Thus, mixing PNN with PZ is expected to decrease the sintering temperature of PZ-based ceramics, which is desirable towards lower-cost electrodes [6].…”