Local electromethanical properties of the CaCu 3Ti 4O 12 ceramics

• Autor(a) principal: Tararam, Ronald [UNESP]
• Data de Publicação: 2010
• Outros Autores: Bdikin, Igor, Varela, José Arana [UNESP], Bueno, Paulo Roberto [UNESP], Gracio, José, Kholkin, Andrei
• Tipo de documento: Artigo de conferência
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1557/PROC-1255-M03-19; http://hdl.handle.net/11449/72072
• topic: Electrical bias; Flexoelectric effects; Grain orientation; In-plane; Induced polarization; Out-of-plane; Piezoelectric signals; Piezoelectric vibration; Polished surfaces; Room temperature; Strain gradients; Ceramic materials; Perovskite; Probes; Scanning probe microscopy; Piezoelectricity

Scanning probe microscopy (SPM) was used to probe piezoelectric vibrations and local conductivity in CaCu 3Ti 4O 12 (CCTO) ceramics at room temperature. Piezoelectric contrast was observed on the polished surfaces of CCTO in both vertical (out-of-plane) and lateral (in-plane) modes and depended on the grain orientation varying in sign and amplitude. The piezoelectric contrast is shown to be controlled by the electrical bias (local poling) and displayed a ferroelectric-like reversible hysteresis accompanied with a change of the phase of piezoelectric signal. Flexoelectric effect (strain-gradient-induced polarization) due to surface relaxation was invoked to explain the observed contrast inside the grains. © 2010 Materials Research Society.