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[Display omitted] • Displacements and impedance of a cantilevered bidomain LiNbO 3 crystal can be described by a 1D model of an ideal bimorph. • Solving the inverse problem of fitting the experimental points allows one to obtain the material's constants. • The predictability of the behavior of LiNbO 3 bimorphs is a unique property for precise lead-free actuators. The study demonstrates that the dynamic characteristics of piezoelectric bimorph actuators based on bidomain lithium niobate (BLN) single crystals are accurately described by an analytical one-dimensional (1D) model of an ideal bimorph. Our observations show that displacements and an electric impedance of the BLN-based bimorphs can be predicted without use of any sophisticated lumped circuit models, equations with handpicked "effective" values of material's constants or finite element method. The experimental data were measured by means of laser interferometry and impedance spectroscopy and then fitted with the equations predicted by the 1D model. Solving the inverse problem for the experimental points we calculated the transverse piezoelectric coefficient, longitudinal mechanical compliance, dielectric permittivity, and piezoelectric coupling coefficient of the material. The obtained values of the material constants of the lithium niobate y + 128°-cut crystal are d 23 = 25 pC/N, s 33 E = 7.58 TPa−1, ε 22 T = 52.7 ε 0 , and k 23 2 = 0.18, which are in excellent agreement with the literature data. [ABSTRACT FROM AUTHOR]

With the recent thriving of low-power electronic microdevices and sensors, the development of components capable of scavenging environmental energy has become imperative. In this article, we studied bidomain congruent LiNbO3 (LN) single crystals combined with magnetic materials for dual, mechanical, and magnetic energy harvesting applications. A simple magneto-mechano-electric composite cantilever, with a trilayered long-bar bidomain LN/spring-steel/metglas structure and a large tip proof permanent magnet, was fabricated. Its vibration and magnetic energy harvesting capabilities were tested while trying to optimize its resonant characteristics, load impedance, and tip proof mass. The vibration measurements yielded a peak open-circuit voltage of 2.42 kV/g, a short-circuit current of $60.1~\mu \text{A}$ /g, and an average power of up to 35.6 mW/g2, corresponding to a power density of 6.9 mW/(cm $^{{3}}\cdot \text {g}^{{2}}$), at a low resonance frequency of 29.22 Hz and with an optimal load of 40 $\text{M}\Omega $. The magnetic response revealed a resonant peak open-circuit voltage of 90.9 V/Oe and an average power of up to $49.9~\mu \text{W}$ /Oe2, corresponding to a relatively large magnetoelectric coefficient of 1.82 kV/(cm $\cdot $ Oe) and a power density of $9.7~\mu \text{W}$ /(cm $^{{3}}\cdot \text {Oe}^{{2}}$). We thus developed a system that is, in principle, able to scavenge electrical power simultaneously from low-level ambient mechanical and magnetic sources to feed low-power electronic devices. [ABSTRACT FROM AUTHOR]

The paper describes the magnetoelectric (ME) effect in a gradient laminate structure consisting of a LiNbO3/Ni/metglas multilayer based on a bidomain lithium niobate single crystal with a Y + 128° cut. The main purpose of the work is to obtain a self‐biased structure. A theoretical and experimental study is conducted to determine the optimal thickness of the Ni film for creating such a structure. The application of self‐biased structures based on gradient bidomain crystals in ME devices can significantly reduce their weight and dimensions as well as improve their electrical characteristics. [ABSTRACT FROM AUTHOR]

Low-frequency vibration energy harvesting is becoming increasingly important for environmentally friendly and biomedical applications in order to power various wearable and implanted devices. In this paper, we propose the use of piezoelectric congruent LiNbO3 (LN) single crystals, with an engineered bidomain structure, as an alternative to the widely employed lead-based PZT. We thus compared experimentally the pure vibration energy scavenging performance of square-shaped bidomain and single-domain Y+128°-cut LN crystals and a conventional bimorph soft PZT ceramic bonded to long spring-steel cantilevers as a function of the frequency, load resistance, and tip proof mass. At a low bending resonance frequency of ca. 32.2 Hz, the bidomain LN yielded an open-circuit voltage of 1.54 kV/g, almost one order of magnitude larger than that observed in PZT. The maximum extractable average power was found to be of 9.2 mW/g2 in the bidomain LN, 6.2 mW/g2 in the single-domain LN, and 1.8 mW/g2 in the PZT piezo-elastic cantilevers. With five times higher output power density of up to 11.0 mW/(cm $^{3}\cdot \text {g}^{2}$) under resonance conditions, bidomain LN was thus shown to be a reliable lead-free and high-temperature alternative to PZT, thanks to its considerably larger quality factor and electromechanical conversion efficiency. [ABSTRACT FROM AUTHOR]