Comparison of effective parameters of lead-free 1–3-type composites based on ferroelectric single crystals

Abstract

The article reports results of the comparative study on the performance of lead-free 1–3-type composites based on domain-engineered lead-free ferroelectric single crystals. Of interest are the 1–3–0 ferroelectric single crystal/porous polymer and 1–0–3 ferroelectric single crystal/piezoelectric single crystal/polymer composites with heterogeneous matrices. In the 1–3–0 composite this matrix is a polymer medium with the system of spheroidal air pores. In the 1–0–3 composite the polymer matrix contains a system of spheroidal piezoelectric single crystal inclusions, and the arrangement of these inclusions is similar to that of the pores in the matrix of the related 1–3–0 composite. Volume-fraction and aspect-ratio dependences of the piezoelectric properties, squared figure of merit and electromechanical coupling factors of the 1–3-type composites are analysed, and comparison of the effective parameters of the composites is made. The role of the composite microgeometry in forming the piezoelectric anisotropy and squared figures of merit is discussed. Due to large electromechanical coupling factors, squared figures of merit and anisotropy factors, the studied lead-free 1–3-type composites are of interest as advanced materials suitable for piezoelectric transducer, sensor and energy-harvesting applications.