Silver niobate based lead-free ceramics with high energy storage density

Electrical field dependence of permittivity in (1 − x)AN-xBZN ceramics. Arrow directions down, up and down then up are related to domain switching, field induced transition and domain switching plus field induced transitions, respectively.</p

Status and Perspectives of Multiferroic Magnetoelectric Composite Materials and Applications

Multiferroic magnetoelectric (ME) composites are attractive materials for various electrically and magnetically cross-coupled devices. Many studies have been conducted on fundamental understanding, fabrication processes, and applications of ME composite material systems in the last four decades which has brought the technology closer to realization in practical devices. In this article, we present a review of ME composite materials and some notable potential applications based upon their properties. A brief summary is presented on the parameters that influence the performance of ME composites, their coupling structures, fabrications processes, characterization techniques, and perspectives on direct (magnetic to electric) and converse (electric to magnetic) ME devices. Overall, the research on ME composite systems has brought us closer to their deployment

Exceeding milli-watt powering magneto-mechano-electric generator for standalone-powered electronics

In contrast to typical magnetic energy generators that use electromagnetic induction, which are bulky and have low generation efficiency under small magnetic fields at low frequency, magneto-mechano-electric (MME) generators utilizing the magnetoelectric (ME) coupling effect and magnetic interactions are considered promising candidates. MME generators will serve as a ubiquitous autonomous energy source converting stray magnetic noise to useful electric energy for applications in wireless sensor networks (WSN) for the Internet of Things (IoT) and low-power-consuming electronics. The key component in a MME generator is the ME composite consisting of piezoelectric and magnetostrictive materials, which elastically couples the electric and magnetic behaviour of the respective constituent. Here, we report a MME generator consisting of a crystallographically oriented Pb(Mg1/3Nb2/3)O-3-Pb(Zr,Ti)O-3 piezoelectric single crystal macro-fibre composite and a highly textured magnetostrictive Fe-Ga alloy, which exhibits an exceptionally high rectified DC output power density of 3.22 mW cm(-3). The large energy generation in this structure is ascribed to the coupling between the strong anisotropic properties of the piezoelectric single crystal fibres and textured Fe-Ga magnetostrictive alloy. A smart watch with IoT sensors was driven by the MME generator under a 700 mu T magnetic field

Enhanced off-resonance magnetoelectric response in laser annealed PZT thick film grown on magnetostrictive amorphous metal substrate

A highly dense, 4 mu m-thick Pb(Zr, Ti)O-3 (PZT) film is deposited on amorphous magnetostrictive Metglas foil (FeBSi) by granule spray in vacuum process at room temperature, followed by its localized annealing with a continuous-wave 560 nm ytterbium fiber laser radiation. This longer-wavelength laser radiation is able to anneal the whole of thick PZT film layer without any deteriorative effects, such as chemical reaction and/or atomic diffusion, at the interface and crystallization of amorphous Metglas substrate. Greatly enhanced dielectric and ferroelectric properties of the annealed PZT are attributed to its better crystallinity and grain growth induced by laser irradiation. As a result, a colossal off-resonance magnetoelectric (ME) voltage coefficient that is two orders of magnitude larger than previously reported output from PZT/Metglas film-composites is achieved. The present work addresses the problems involved in the fabrication of PZT/Metglas film-composites and opens up emerging possibilities in employing piezoelectric materials with low thermal budget substrates (suitable for integrated electronics) and designing laminate composites for ME based devices. (C) 2015 AIP Publishing LLC.11Nsciescopu

A flexible, high-performance magnetoelectric heterostructure of (001) oriented Pb(Zr0.52Ti0.48)O3 film grown on Ni foil

In this study, a flexible magnetoelectric (ME) heterostructure of PZT/Ni was fabricated by depositing a (001) oriented Pb(Zr0.52Ti0.48)O3 (PZT) film on a thin, flexible Ni foil buffered with LaNiO3/HfO2. Excellent ferroelectric properties and large ME voltage coefficient of 3.2 V/cm⋅Oe were realized from the PZT/Ni heterostructure. The PZT/Ni composite’s high performance was attributed to strong texturing of the PZT film, coupled with the compressive stress in the piezoelectric film. Besides, reduced substrate clamping in the PZT film due to the film on the foil structure and strong interfacial bonding in the PZT/LaNiO3/HfO2/Ni heterostructure could also have contributed to the high ME performance of PZT/Ni

Growth of self-textured barium hexaferrite ceramics by normal sintering process and their anisotropic magnetic properties

In this report a simple and low-cost technique for growing highly textured barium hexaferrite ceramics without the need for flux or seed crystals to achieve grain orientation is demonstrated. Plate-like shaped barium hexaferrite particles were synthesized using a solid-state reaction process and then aligned under a weak magnetic field, followed by uniaxial compaction. The aligned hexaferrite particles appear to serve as seeds, forming textured grains during sintering. The development of texture was verified by X-ray diffraction (XRD), electron backscatter diffraction (EBSD), and vibration sample magnetometer (VSM) measurements. The prepared high-quality hexaferrite ceramics exhibited good anisotropic magnetic properties, comparable to those of single crystal counterparts. A mechanism for the formation of the self-textured grain growth of the barium hexaferrite ceramics, which involves grain boundary and lattice diffusion and interface reaction processes, is proposed. (C) 2017 Elsevier Ltd. All rights reserved.113Nsciescopu