Domain-engineered relaxor-ferroelectric single crystals with compositions near the morphotropic phase boundary are considered as a key component for modern high-performance piezo-active composites. The advantages of using the relaxor-ferroelectric single crystals of solid solutions of (1 − x)PbIJMg 1/3 Nb 2/3 )O 3 − xPbTiO 3 and (1 − y)Pb(Zn 1/3 Nb 2/3 )O 3 − yPbTiO 3 in piezo-active composites of 2-2 and 1-3 configurations are discussed by taking into account the complex relationships between the outstanding properties of the components and the effective parameters of the composite structure as a whole. Examples of their high piezoelectric activity, strong electromechanical coupling, large piezoelectric anisotropy, and large hydrostatic parameters of the composites demonstrate how the relaxor-ferroelectric single-crystal component improves the effective parameters and promotes the formation of non-monotonic volume-fraction dependences of particular effective parameters that are of interest for a variety of piezotechnical applications, such as transducers, sensors, hydrophones, and energy-harvesting devices. CrystEngCommThis journal is

No abstract

The paper is devoted to the analysis of high-performance piezo-composites based on lead-free ferroelectric single crystals. The composite consists of parallelepiped-shaped single-crystal rods which are surrounded by a laminar polymer matrix, and the composite as a whole is described by 1-2-2 connectivity. Such a composite structure promotes high piezoelectric sensitivity and hydrostatic response. Of particular interest are piezoelectric coefficients g Mn single crystals. The role of elastic properties of the laminar matrix in achieving large hydrostatic parameters and piezoelectric anisotropy of these composites is emphasised. Their effective parameters are compared to those of composites based on the lead-containing relaxor-ferroelectric single crystals and to specific parameters of poled textured ceramics. Advantages of the studied composites over the relaxor-ferroelectric-based composites and textured ceramics open up new possibilities to apply the 1-3-type lead-free composites as active elements of piezoelectric sensors, hydrophones, energyharvesting, and transducer devices.

No abstract