Excellent piezo-/pyro-/ferroelectric performance of Na0.47K0.47Li0.06NbO3 lead-free ceramic near polymorphic phase transition

An excellent piezoelectric charge coefficient (d33 = 450 pCN−1) was obtained in lead-free Na0.47K0.47Li0.06NbO3 ceramic by optimized sintering temperature with uniform and dense grains. It showed orthorhombic to tetragonal polymorphic phase transition at 24 oC and a high Curie temperature (470 oC). It also exhibited good, fatigue-free ferroelectric properties and a high pyroelectric coefficient (1106.1 μCm−2 oC−1). Thus, K0.5Na0.5NbO3-based ceramics with uniform grains are good candidates of piezo-/ferroelectric applications.