Improvement of electrical and energy harvesting properties of new lead-free BST modified 0.995BNKT–0.005LN ceramics. Issue 1 (2nd January 2023) - Wannasut, Pimpilai
ABSTRACT: New lead-free (1- y )[0.995Bi0.5 (Na0.80 K0.20 )0.5 TiO3 -0.005LiNbO3 ]- y [(Ba0.7 Sr0.3 )TiO3 ] or (1- y )[0.995BNKT-0.005LN]- y [BST] (where y = 0, 0.01, 0.02, 0.03, 0.04 and 0.05 mol fraction) ceramics were fabricated by a conventional sintering method with two calcination steps. All ceramics sintered at 1125°C for 2 hours showed an optimum relative density of ~98% and a linear shrinkage of ~18%. X-ray diffraction patterns indicated that all ceramics possessed a pure perovskite phase with coexisting rhombohedral and tetragonal structures. Electrical and energy harvesting properties of 0.995BNKT–0.005LN ceramics were improved with 0.03 mol fraction BST addition ( d 33 = 287 pC/N, d *33 = 440 pm/V, g33 = 13.40 × 10 −3 V/mN and FoM = 3.85 pm 2 /N). From the observed results, the 0.97[0.995BNKT-0.005LN]-0.03[BST] ceramic is a promising candidate for lead-free piezoelelectric sensor-actuator and energy harvester.