High energy-density 0.72Pb(Zr_0.47Ti_0.53)O₃-0.28Pb[(Zn_0.45Ni_0.55)_1/3Nb_2/3]O₃ thick films fabricated by tape casting for energy-harvesting-device 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 (e{open} ₃₃ ^T /e{open} 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, e{open} ₃₃ ^T /e{open} 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.