Multifunctional barium titanate ceramics via chemical modification tuning phase structure

Abstract

Global environmental concerns on the toxicity of lead‐based piezoelectrics impel the great mass fervor on investigations of lead‐free alternatives. Barium titanate (BaTiO3, BT) ceramics, the first discovered perovskite ferroelectrics, were widely employed to fabricate dielectric capacitors from 1950s. Since a piezoelectric breakthrough was achieved via chemical modification, intensive researches have been performed embracing lead‐free BT‐based piezoelectrics and their extensional functionalities. In this review, we encompass the state‐of‐the‐art progress on chemical modification tuning phase structure toward advanced electrical properties in BT‐based ceramics. Generally, modulated regularity of cations substitution on phase transition is summarized and clarified. Then, we highlight the common methodologies of phase structure (phase boundary, relaxor phase, room‐temperature phase transition, etc.) design for optimizing piezoelectricity, electrostrictive strain, electrocaloric, dielectric energy storage or permittivity performances, and cover the noticeable developments and relevant physical mechanisms. Finally, perspectives and challenges on future research issues are featured. This review proposes to exert the significant guidance and service for material design of BT‐based and other lead‐free perovskite materials with superior functionalities.

WITHDRAWN: Unraveling Dielectric Abnormality Based on the Effect of Defect Dipoles in Cr Ion Doped Multipurpose Properties of BCT Ceramics

“…BCT (Ca doping in BaTiO3) ceramics support the diffused temperature dependence of dielectric constant, provide higher breakdown strength, and better piezoelectric properties [2,14,[29][30][31][32]. Moreover, doping effect of Ca on temperature-dependent transitions of BaTiO3, tetragonal-cubic transition temperature (at ̴ 120 ˚C) shows negligible variation, but lowers the transition temperature of tetragonalorthorhombic (at ̴ 5 ˚C) and orthorhombicrhombohedral (at ̴ -80 ˚C) phase [1,15,30,33]. Further, Ca doping also prevents the formation of an undesired hexagonal phase and greatly improves the performance of BaTiO3 ceramics [1,30,34].…”

“…But the presence of highly precarious Lead (Pb) raised concerns regarding detrimental effects on human health and the environment, and forbid their usefulness [3,13,14]. New ceramic compositions need to be designed to replace Pb and derive the improved performance of Lead-free materials in a variety of achievable properties [13,15,16]. For the last few decades, the enthralling research into Lead-free ceramics has been conducted [17].…”

“…Currently, the search for Lead-free dielectric ceramics with ergonomic properties is focused on the compositions of BaTiO3, which is a well-studied perovskite ferroelectric material due to its enormous practical applications [13,[18][19][20][21]. Modification in the structure and properties of BaTiO3 can be made by doping with a variety of dopant ions (dopant engineering) for fetching multiple applications from doped ceramic materials [5,15,20,[22][23][24][25][26][27]. The properties of ceramic materials are highly dependent on final crystal symmetry, choice of dopant, the disparity in ionic radii between host/parent and dopant cations, doping concentration, and preparation conditions [28] The A-site substitution of smaller ionic radii Ca 2+ (1.34 Å) in BaTiO3 is caused by replacing Ba 2+ ions with larger ionic radii (1.61 Å) within its solid solution limit.…”

Mechanical Manipulation of Nano‐Twinned Ferroelectric Domain Structures for Multilevel Data Storage

“…Ferroelectrics hold the promise to revolutionize low‐power logic, nonvolatile memories, actuators, sensors, and electro‐optics for waveguide devices. [ 1–24 ] These applications require suitable control and manipulation of ferroelectric domains and domain walls in ferroelectric thin films. Since 180° polarization switching was accomplished in 4.8 nm thick tetragonal BaTiO 3 thin films via mechanical manipulation, [ 25 ] considerable effort has been devoted to manipulating the polarization switching in ferroelectric thin films, for example, 3–5 nm thick PbZr 0.2 Ti 0.8 O 3 (001) film, 1.6–45 nm thick BaTiO 3 (001) film, 50 nm thick PbZr 0.1 Ti 0.9 O 3 (001) film, and 10 nm thick PbZr 0.48 Ti 0.52 O 3 (001) film, and flexoelectric effect is proposed to explain the mechanical manipulation of the domain and domain wall structures.…”

Liquid‐phase preparation of BaTiO3nanoparticles

“…When the temperature is <120°C, the other crystal phases (the rhombohedral phase, the orthogonal phase and the tetragonal phase) have spontaneous polarisation, which is characterised by ferroelectricity [9,10]. Therefore, the paraelectricity and the ferroelectricity [11][12][13][14] of BT ceramics are closely related to the phase transition.…”