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Conventionally, effective mechanical vibration energy harvesting is based on (Pb,Zr)TiO3 (PZT) ceramics, poly(vinylidene fluoride) (PVDF) polymers or PVDF/PZT or other piezoelectric composite materials, and their working temperature is normally limited to room temperature (R-T) or below 150 °C. Here, bismuth scandium lead titanate (BiScO3-PbTiO3, abbreviated as BSPT) ceramic is reported which has a high Curie temperature point around 450 °C and its application for high-temperature (H-T) vibration energy harvesting. Experimental results show that it exhibits an excellent H-T piezoelectricity, converting mechanical vibration energy into electric power effectively in a wide temperature range from R-T till 250 °C. This research shows the BSPT piezoelectric energy harvester having the potential application for self-power source of wireless sensor network system in high temperature circumstance.

The perovskite solid solution system of (1−x−y)(Na0.5K0.5)NbO3–xBaZrO3–y(Bi0.5Li0.5)TiO3 (BZ/BLT/NKN) is a new family of lead-free piezoelectric material. Compositions near the morphotropic phase boundary (MPB) (x = 0.06, y = 0.02) have been reported to have good piezoelectric coefficients with the moderate Curie temperature. In this work, the full set of material constants for the MPB composition of BZ/BLT/NKN solid solution was characterized using the resonance method. e 33 T , tanδ, d31, d33, d15, Qm and TC are 2496, 0.025, −159 pC/N, 321 pC/N, 602 pC/N, 44 and 256 °C, respectively. The piezoelectric properties are not only superior to those of other (Na,K)NbO3-based ceramics at room temperature, but also relatively stable against temperature up to 200 °C. These results show that BZ/BLT/NKN solid solution is a promising candidate for practical piezoelectric applications in actuating and sensing fields.

Micro/nanomaterials and devices have attracted great interest in recent years because of their extensive application prospects in almost all kinds of fields. However, the manipulations of the material at the micro/nanoscale, such as the separation or transfer of a micro/nano-object in the process of assembling micro/nanodevices, are quite difficult. In this paper, we present a micromachined micro-gripper made of photoresist material (SU-8) and driven by piezoelectric Pb(Mg,Nb)O3–PbTiO3 single crystal pieces. In order to keep two grasping jaws of the micro-gripper operating in the same plane at the micro/nanometer scale, a fine circular flexure hinge was fabricated for elastically connecting them together. After introducing the interface effect, the relationship between the opening stroke of two jaws and the applied voltage was developed and then confirmed by finite element simulation. The micro-gripper was finally installed on a six degree of freedom stage for performing a pick-up, release, and transfer manipulation of a 2 μm ZnO micro-fiber. The presented piezoelectric micro-gripper shows a great potential for the precise manipulation of a single piece of micro/nanomaterial for micro/nanodevices’ assembling.

Bulk-magnetoelectric (ME) composites consisting of various piezoelectric and piezomagnetic materials with (3-0), (3-1), (2-2), and (2-1) connectivity are proposed in a bid to realize strong ME coupling for next-generation electronic-device applications. Here, 1D (1-1) connectivity ME composites consisting of a [011]-oriented Pb(Mg,Nb)O3-PbTiO3 (PMN-PT) single-crystal fiber laminated with laser-treated amorphous FeBSi alloy (Metglas) and operating in L-T mode (longitudinally magnetized and transversely poled) are reported, which exhibit an enhanced resonant ME coupling coefficient of ≈7000 V cm−1 Oe−1, which is nearly seven times higher than the best result published previously, and also a superhigh magnetic sensitivity of 1.35 × 10−13 T (directly detected) at resonance at room temperature, representing a significant advance in bulk magnetoelectric materials. The theoretical analyses based on magnetic-circuit and equivalent-circuit methods show that the enhancement in ME coupling can be attributed to the reduction in resonance loss of laser-treated Metglas alloy due to nanocrystallization and the strong magnetic-flux-concentration effect in (1-1) configuration composites.

(1-x)BiScO3–xPbTiO3 (BS–PT) high temperature piezoelectric ceramics were prepared by traditional solid-state reaction method. Combining X-ray diffraction (XRD) results with piezoelectric results, it was found that the morphotropic phase boundary (MPB) is near x = 0.633. The whole set of material constants, such as elastic (sij, cij), piezoelectric (dij, eij, gij, hij), dielectric (eij, βij), and electromechanical coupling coefficients (kij) for MPB composition were obtained by the resonance method from room temperature to 450 oC. The values of d33, −d31, d15, g33, and Qm for MPB composition at room temperature were 441 pC/N, 117 pC/N, 620 pC/N, 47.3 × 10−3 Vm/N, and 28, respectively. Temperature-dependent free dielectric e ij T , elastic s ij T , and electromechanical coupling coefficients kij for MPB composition were extremely stable from room temperature up to 350 oC. The systematical characterization of dielectric, piezoelectric, and elastic coefficients in the wide temperature range (from room temperature to 450 oC) may promote the design and application of high temperature piezoelectric sensors and actuators based on BS–PT ceramics.

The non-magnetostrictive magnetoelectric (ME) effect was realized in a simple ferromagnetic–elastic–piezoelectric (FEP) composite. The FEP composite comprised two piezoceramic Pb(Zr,Ti)O3 (PZT) plates and NdFeB magnets elastically coupled by a cantilever beam made of phosphor copper-sheet. The effects of the beam length on the ME coefficient and the linear relationship between the ME voltage output and the applied magnetic field at the resonant frequency were experimentally investigated. A notably superior ME coefficient of 3800 V/cm Oe at extremely low resonant frequency of 5.524 Hz was obtained for the FEP composite with the phosphor copper-sheet beam length of 8 cm. Such a composite structure shows the possibility to obtain a magnetic sensor element with ultrahigh sensitivity in low frequency range. The results are of great importance for the basic understanding of the new way to realize giant ME effect and the optimal design of such a composite structure with high ME coefficient.

A magnetoelectric (ME) flux gate sensor (MEFGS) consisting of piezoelectric PMN-PT single crystals and ferromagnetic amorphous alloy ribbon in a self-differential configuration is featured with the ability of weak magnetic anomaly detection. Here, we further investigated its ME coupling and magnetic field detection performance in vibration noise circumstance, including constant frequency, impact, and random vibration noise. Experimental results show that the ME coupling coefficient of MEFGS is as high as 5700 V/cm*Oe at resonant frequency, which is several orders magnitude higher than previously reported differential ME sensors. It was also found that under constant and impact vibration noise circumstance, the noise reduction and attenuation factor of MEFGS are over 17 and 85.7%, respectively. This work is important for practical application of MEFGS in real environment.

In this work, a wave-shaped piezoelectric composite (WSPC) made of fine β-phase vinylidene fluoride trifluoroethylene copolymer (P(VDF-TrFE)) polymer and high-elastic FeSiB amorphous alloy (metglas) ribbon has been successfully fabricated for wearable device applications. X-ray diffraction and the Fourier Transform Infrared Spectrum studies reveal P(VDF-TrFE) exhibiting the fine β-phase. Both theoretical analysis and experimental results show that unique wave-shaped structure enhances the electromechanical coupling significantly, because of the combination piezoelectric effects of d33 and d31 modes in P(VDF-TrFE) polymer, as well as the enhanced effective piezoelectric coefficient caused by the pre-stretch in P(VDF-TrFE) film. Two application examples of WSPC, (i) mechanical force sensor or energy harvester, and (ii) the medical blood-pressure pulse sensor, have been investigated, which show that the WSPC is a promising candidate for future wearable device applications.

In this study, we investigate the converse magnetoelectric (CME) effect in a laminated composite consisting of Metglas ribbons and Pb(Zr,Ti)O3 (PZT) plate with screen-printed interdigitated electrodes and operating in longitudinal magnetization and longitudinal polarization (L-L) mode. Large CME coefficients of 0.134 G·cm/V at frequency of 1 kHz and 2.75 G·cm/V at resonance frequency of 43.5 kHz under a small bias magnetic field of 7 Oe are achieved. The large CME effect can be attributed to the L-L mode and low mechanical loss of the Metglas/PZT laminated composite.

We report a piezoelectric pseudo-bimorph actuator, which is made of only one single plate with interdigitated electrodes on both sides and polarized alternately in longitudinal direction. Like a bimorph actuator, it can also produce a large bending actuation based on anti-symmetrically longitudinal piezoelectric d33 strain effect under an applied electric field. The presented pseudo-bimorph actuator shows much better temperature stability than conventional piezoelectric bimorph actuators from room temperature to the depolarization temperature of the material due to lacking of interface strain loss.

The current paper reports a digital piezoelectric bimorph actuator having segmented electrodes and producing 2 to the nth power digital bending actuation in on/off switch mode and under a fix applied voltage. Correspondingly, a simple model for predicting digital actuation under applied coding voltage is also presented. Experimental results have confirmed that the proposed actuator can produce a linear digital displacement without a hysteresis loop. The proposed method is significant for open-loop high precise actuation.

Hard piezoelectric ceramics of manganese (Mn)-modified 0.36BiScO3–0.64PbTiO3 (0.36BS–0.64PTM) with a high Curie temperature were prepared using the traditional solid-state reaction method. The effects of different concentrations of Mn on the structure, dielectric and piezoelectric properties of the 0.36BS–0.64PTM ceramics were investigated. X-ray diffraction results indicated that the 0.36BS–0.64PTM ceramics showed a single perovskite structure with tetragonal symmetry and the c/a ratio decreased slightly with increasing Mn content. The grain sizes of the 0.36BS–0.64PTM ceramics were enlarged by Mn addition, and their distributions were uniform. The dielectric loss tan δ decreased clearly with the increase in Mn content, and the mechanical quality factor Q m and vibration velocity v 0 were improved significantly at the same time. The Curie temperature T c, the planar electromechanical coupling factor k p, dielectric loss tan δ, mechanical quality factor Q m and vibration velocity v 0 of the 0.36BS–0.64PTM ceramics with 3 mol% Mn were about 431 °C, 0.57, 0.007, 134 and 1.05 m s−1, respectively. The maximum vibration velocity v 0 of the 0.36BS–0.64PTM ceramics is much superior to those of PZT (0.4 m s−1) ceramics and PZT–PZM (0.72 m s−1). These results indicated that the 0.36BS–0.64PTM ceramics are promising candidates for high-temperature and high-power piezoelectric applications.

Colossal low-frequency resonant magnetomechanical (MM) and magnetoelectric (ME) coupling effects have been found in a three-phase composite made of Pb(Zr,Ti)O3 ceramic fibers/phosphor copper-sheet unimorph and NdFeB magnets. The experimental results revealed that the ferromagnetic/elastic/piezoelectric three-phase composite with a cantilever beam structure could show huge bending MM coefficient of ∼145.9 × 10−3/Oe (unit in bending radian per Oe) and ME voltage coefficient of ∼16 000 V/cm·Oe at the first-order bending resonance frequency of ∼5 Hz. The achieved results related to ME effect are at least one order of magnitude higher over those of other ME materials and devices reported ever. The extremely strong MM and ME couplings in the three-phase composite are due to strong magnetic force moment effect induced by the interaction between NdFeB magnets and the applied magnetic field, and further resonant enhancement via the strain-mediated phosphor copper-sheet with a relatively high mechanical quality factor.