Horizontally assembled trapezoidal piezoelectric cantilevers driven by magnetic coupling were fabricated for rotational energy harvester applications. A dodecagonal rigid frame with an attached array of six trapezoidal cantilevers served as a stator for electrical power generation. A rotor disk with six permanent magnets (PMs) interacted magnetically with the counterpart cantilever’s tip-mass PMs of the stator by rotational motion. Each trapezoidal piezoelectric cantilever beam was designed to operate in a transverse mode that utilizes a planar Ag/Pd electrode printed onto lead zirconate titanate (PZT) piezoelectric thick film. The optimized distance between a pair of PMs of the rotor and the stator was evaluated as approximately 10 mm along the same vertical direction to make the piezoelectric cantilever beam most deflectable without the occurrence of cracks. The theoretically calculated resistance torque was maximized at 46 mN·m for the optimized trapezoidal piezoelectric cantilever. The proposed energy harvester was also demonstrated for wind energy harvester applications. Its harvested output power reached a maximum of approximately 22 mW at a wind speed of 10 m/s under a resistive load of 30 kΩ. The output performance of the proposed energy harvester makes it possible to power numerous low-power applications such as smart sensor systems.

The dielectric properties of the amorphous BaSm 2 Ti 4 O 12 (BSmT) film with various thicknesses were investigated to evaluate its potential use as a metal-insulator-metal (MIM) capacitor. An amorphous 35-nm-thick BSmT film grown at 300 degC exhibited a high capacitance density of 9.9 fF/mum 2 at 100 kHz and a low leakage current density of 1.790 nA/cm 2 at 1 V. The quadratic and linear voltage coefficients of capacitance of the film were 599 ppm/V 2 and -81 ppm/V at 100 kHz, respectively. The temperature coefficient of capacitance of the film was also low about 236 ppm/degC at 100 kHz. These results confirmed the suitability of the amorphous BSmT film as a high-performance MIM capacitor

A novel 0.36BiScO₃-0.64PbTiO₃ (0.36BS-0.64PT) textured ceramic was developed using plate-like BaTiO₃ (BT) templates for high temperature piezoelectric device applications. Sintering temperature and amount of BT template played important roles in improving the density, crystal orientation, and ferroelectric and piezoelectric properties of the BT-templated 0.36BS-0.64PT thick films. When sintered at 1000°C, highly dense BS-PT textured films were obtained without formation of a secondary phase. The increased amount of BT template facilitated the degree of texture but deteriorated the relative density of BS-PT thick film. In particular, enhanced ferroelectric and piezoelectric properties were obtained for 1 vol% BT-templated 0.36BS-0.64PT thick film sintered at 1000°C; this film exhibited the very large P_r (44.2 μC/cm² at 4 kV/mm), d₃₃ (444 pC/N), k_p (57.4%), and g₃₃ (36 × 10⁻³Vm/N) values. In addition, considering the inverse relation between T_C and strain, the electrostrain of d₃₃* (622 pm/V at 4 kV/mm) was excellent, showing potential for piezoelectric actuator applications.

0.72Pb(Zr_0.47Ti_0.53)O₃-0.28Pb[(Zn_0.45Ni_0.55)_1/3Nb_2/3]O₃ (0.72PZT-0.28PZNN) thick films were prepared by using a tape casting method to develop new materials with high energy-density applicable to energy-harvesting devices. The piezoelectric strain constant (d ₃₃), dielectric constant (ɛ ₃₃ ^T /ɛ ₀), piezoelectric voltage constant (g ₃₃) and transduction coefficient (d ₃₃·g ₃₃) of the films were affected by the sintering temperature. These results could be attributed to the crystal structure, microstructures and secondary phases. However, the dielectric loss (tanδ) of the films was not changed remarkably with increasing sintering temperature. Typically, a d ₃₃ of 452 pC/N, ɛ ₃₃ ^T /ɛ ₀ of 1444, d ₃₃·g ₃₃ of 20,340 × 10⁻¹⁵ m²/N and tanδ of 0.15% were obtained for the films sintered at 1050 °C for 1 h. The power generation performance of the piezoelectric unimorph cantilever was assessed to demonstrate the feasibility of the 0.72PZT-0.28PZNN piezoelectric thick film. Also, theoretical models were employed to predict the resonance frequency of the unimorph cantilever generator, and the predicted values were compared with experimental data.