In this research article, the effects of Al2O3 nanoparticles (0-1.0 mol%) on the phase formation, microstructure, dielectric, ferroelectric, piezoelectric, electric field-induced strain and energy harvesting properties of the 0.94(Bi0.5Na0.5)TiO3-0.06BaTiO3 (BNT-6BT) ceramic were investigated. All ceramics have been synthesized by a conventional mixed oxide method. The XRD and Raman spectra showed coexisting rhombohedral and tetragonal phases throughout the entire compositional range. An increase of the grain size, T F-R, T m, ε max and δ A values was noticeable when Al2O3 was added. Depolarization temperature (T d), which was determined by the thermally stimulated depolarization current (TSDC), tended to increase with Al2O3 content. The good ferroelectric properties (P r = 32.64 μC cm-2, E c = 30.59 kV cm-1) and large low-field d 33 (205 pC N-1) values were observed for the 0.1 mol% Al2O3 ceramic. The small Al2O3 additive improved the electric field-induced strain (S max and ). The 1.0 mol% Al2O3 ceramic had a large piezoelectric voltage coefficient (g 33 = 32.6 × 10-3 Vm N-1) and good dielectric properties (ε r,max = 6542, T d = 93 °C, T F-R = 108 °C, T m = 324 °C and δ A = 164 K). The highest off-resonance figure of merit (FoM) for energy harvesting of 6.36 pm2 N-1 was also observed for the 1.0 mol% Al2O3 ceramic, which is suggesting that this ceramic has potential to be one of the promising lead-free piezoelectric candidates for further use in energy harvesting applications.
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