Abstract
For many BNT-based ceramics, an attempt to increase the piezoelectric properties usually results in a decrease in depolarization temperature (T (d)). This trend limits the applications of the materials. Many previous experiments have used different methods to enhance the piezoelectric properties and improve the T (d) characteristic. In this study, we demonstrated a simple technique (thermal annealing) to enhance the piezoelectric properties with a very slight decrease in T (d) by ∼2 °C for a modified BNKT ceramic (BNKT doped with ZnO). Other phase transition characteristic temperatures of the studied ceramics were also slightly changed. The optimum dielectric (ε (r) = 651, tan δ = 0.0503, T (F-R) = 167.38 °C, T (m) = 305.41 °C, ε (max) = 5551, T (B) = 367.15 °C, T (d) = 155.98 °C, and γ = 1.43), ferroelectric (P (max) = 41.28 μC cm(-2), P (r) = 35.85 μC cm(-2), E (c) = 42.60 kV cm(-1) and R (sq) = 1.42), piezoelectric (d (33) = 198 pC N(-1), k (p) = 0.598, and g (33) = 34.35 × 10(-3) Vm N(-1)), and energy harvesting (FoM = 6.80 pm(2) N(-1)) were obtained for the 8 h annealed ceramic. Furthermore, higher energy harvesting properties (which were 32% higher than that of the unannealed ceramic) were obtained after employing this technique.