Abstract
Recent advances in phase transition transduction enabled the design of a non-resonant broadband mechanical energy harvester that is capable of delivering an energy density per cycle up to two orders of magnitude larger than resonant cantilever piezoelectric type generators. This was achieved in a [011] oriented and poled domain engineered relaxor ferroelectric single crystal, mechanically biased to a state just below the ferroelectric rhombohedral (FR)-ferroelectric orthorhombic (FO) phase transformation. Therefore, a small variation in an input parameter, e.g., electrical, mechanical, or thermal will generate a large output due to the significant polarization change associated with the transition. This idea was extended in the present work to design a non-resonant, multi-domain magnetoelectric composite hybrid harvester comprised of highly magnetostrictive alloy, [Fe81.4Ga18.6 (Galfenol) or TbxDy1-xFe2 (Terfenol-D)], and lead indium niobate–lead magnesium niobate–lead titanate (PIN-PMN-PT) domain engineered relaxor ferroelectric single crystal. A small magnetic field applied to the coupled device causes the magnetostrictive element to expand, and the resulting stress forces the phase change in the relaxor ferroelectric single crystal. We have demonstrated high energy conversion in this magnetoelectric device by triggering the FR-FO transition in the single crystal by a small ac magnetic field in a broad frequency range that is important for multi-domain hybrid energy harvesting devices.
Highlights
The need for a sustainable power source for micro devices, autonomous underwater vehicles, drones, robotics, and remote sensor networks has placed an increasing emphasis on ambient energy harvesting devices that exhibit high converted energy density per cycle with improved efficiency [1,2,3,4,5,6]
We investigated three regimes corresponding to different pre-stress conditions: (i) when the crystal is pre-stressed below the ferroelectric rhombohedral (FR) -ferroelectric orthorhombic (FO) transition; (ii) close to the transition for the stress-induced FR -FO nonlinear phase transformation (PT) region; and (iii) above critical stress sufficient to bring the crystal to FO phase
It is of relevance to point out that the same peak voltage was maintained as the magnetic field relevance to point out that the same peak voltage was maintained as the magnetic field was repeatedly was repeatedly cycled. We demonstrated that this FR-FO phase transformation can cycled
Summary
The need for a sustainable power source for micro devices, autonomous underwater vehicles, drones, robotics, and remote sensor networks has placed an increasing emphasis on ambient energy harvesting devices that exhibit high converted energy density per cycle with improved efficiency [1,2,3,4,5,6]. The device is capable of low frequency energy conversion in the Hertz region and is not frequency-limited up to several kHz by the piezoelectric crystal-load impedance [8] This device is capable of converting variations in environmental temperature to a usable electrical output [9] and can be considered a dual-domain harvester. It operates on a phase transition transduction principle in relaxor ferroelectric crystals that was first reported by Finkel, Benjamin, and Amin [10] and was later utilized in a miniaturized class IV (flex-tensional) acoustic source [11]. Driven strain in this harvester generates sufficient critical stress to induce this phase transformation in mechanically biased single crystal with demonstrated high electromechanical energy conversion in broad range of frequencies [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
