Multifunctional performance and ferroelectric phase characteristic of BCTH-Eu ceramics prepared by low-temperature sintering via LiBO2 doping

Abstract

Multifunctional performance [(Ba0.85Ca0.15)0.995Eu0.005](Ti0.9Hf0.1)O3 (BCTH-Eu) ceramics were prepared by conventional solid-state low-temperature sintering method via LiBO2 doping, in which the sintering aid LiBO2 was introduced into the calcined perovskite precursor powder through liquid phase coating technique. Phase-pure perovskite structure BCTH-Eu ceramics are obtained by the method, and the sintering temperature is decreased about 150 °C as compared with the conventional method whose sintering temperature is normally above 1450 °C. The ceramics present rather high density, uniform distribution of grains and elementals, and have submicron meter grain size. Due to complex substitution of cations at A-site and B-site of the perovskite structure, the LiBO2-doped BCTH-Eu ceramics exhibit displacive driven normal ferroelectrics accompanied by apparent diffused relaxation characteristic. The 1340 °C sintered LiBO2-doped BCTH-Eu ceramics present maximum piezoelectric constant d33 value of 314 pC/N poled under 20 kV cm−1, and the ceramics sintered between 1320 °C–1330 °C exhibit excellent comprehensive electrical properties and multifunctional performance. Such excellent multifunctional properties obtained in this work can be partially attributed to the coexistence of multi-ferroelectric phases, which is confirmed by dielectric response fitting and Raman Gaussian fitting.