Grain-size-dependence of flexoelectric response in giant dielectric CaCu3Ti4O12
Year: 2026
Type: other
Abstract: Grain structure plays a crucial role in the dielectric response of CaCu3Ti4O12 (CCTO) ceramics, attributed to the internal barrier layer capacitor (IBLC) mechanism. Despite the close relation between flexoelectricity and dielectricity, how grain structure affects CCTO flexoelectric response remains unexplored. Here, CCTO ceramics with different grain sizes of 0.8-15 mm were prepared by controlling sintering temperatures. It shows that increased grain size tends to enhance both dielectric and flexoelectric responses, with the dielectric constant varying from ~1300 to ~16700 and the apparent flexoelectric coefficient m12 varying from 6.82 μC/m to 11.73 μC/m, respectively. This indicates that the flexoelectric and dielectric responses in CCTO ceramics are homologous in origin. Impedance measurements further reveal that the Schottky barrier height decreases with increasing grain size, which contributes to the nonlinear evolution of responses. Our study extends understanding of the grain size effect in flexoelectric ceramics and offers guidance for flexoelectric enhancement via grain size modulation.
Source: AIP Publishing
Authors: Weijin Chen, Yuyu Liu, Junyu Tao
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7225629048