Abstract
A superior piezoelectric coefficient (d(33) = 570 +/- 10 pC N-1), the highest value reported to date in potassium-sodium niobate-based ceramics, is obtained in (1-x-y)K1-wNawNb1-zSbzO3-yBaZrO3-x-Bi0.5K 0.5HfO3 ceramics. This high d(33) value can be ascribed to the co-existence of "nano-scale strain domains" (1-2 nm) and a high density of ferroelectric domain boundaries. Therefore, ternary KNN-based ceramics demonstrate the potential for applications.