title: Understanding the peculiarities of the piezoelectric effect in macro-porous BaTiO3.
abstract: This work demonstrates the potential of porous BaTiO3for piezoelectric sensor and energy-harvesting applications by manufacture of materials, detailed characterisation and application of new models. Ferroelectric macro-porous BaTiO3ceramics for piezoelectric applications are manufactured for a range of relative densities,α= 0.30-0.95, using the burned out polymer spheres method. The piezoelectric activity and relevant parameters for specific applications are interpreted by developing two models: a model of a 3-0 composite and a 'composite in composite' model. The appropriate ranges of relative density for the application of these models to accurately predict piezoelectric properties are examined. The two models are extended to take into account the effect of 90° domain-wall mobility within ceramic grains on the piezoelectric coefficients [Formula: see text]. It is shown that porous ferroelectrics provide a novel route to form materials with large piezoelectric anisotropy [Formula: see text] at 0.20 ≤α≤ 0.45 and achieve a high squared figure of merit [Formula: see text] [Formula: see text]. The modelling approach allows a detailed analysis of the relationships between the properties of the monolithic and porous materials for the design of porous structures with optimum properties.
authors.affiliation: Department of Mechanical Engineering, Materials and Structures Centre, University of Bath , Bath , UK.
authors.forename: James I
authors.initials: JI
authors.lastname: Roscow
authors.affiliation: Department of Physics, Southern Federal University , Rostov-on-Don , Russia.
authors.forename: Vitaly Yu
authors.initials: VY
authors.lastname: Topolov
authors.affiliation: Department of Mechanical Engineering, Materials and Structures Centre, University of Bath , Bath , UK.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Bowen
authors.affiliation: Department of Electrical and Electronic Engineering, University of Bath , Bath , UK.
authors.forename: John
authors.initials: J
authors.lastname: Taylor
authors.affiliation: Institute of High Technologies and Piezotechnics, Southern Federal University , Rostov-on-Don , Russia.
authors.forename: Anatoly E
authors.initials: AE
authors.lastname: Panich
keywords: 102 Porous / Nanoporous / Nanostructured materials; 107 Glass and ceramic materials; 202 Dielectrics / Piezoelectrics / Insulators; 50 Energy Materials; Piezoelectric; ferroelectric; microstructure; modelling; porous