Electrical properties of Li doped sodium potassium niobate thick films prepared by a tape casting process

Highlights: → Li doped KNN thick films were prepared by a tape casting process. → The coercive fields decreased with the addition of Li ions. → The thick film with 6 mol% Li exhibited an optimized value of d33 which was 92 pm/V. - Abstract: Lithium doped K0.5Na0.5NbO3 (abbreviated as KNN-xL, with x = 0.02, 0.04, 0.06, 0.08) thick films with a thickness of about 20 μm were prepared by a tape casting process. The presence of Li ions promoted the microstructure of these thick films. Coercive fields (Ec) of the thick films decreased with the addition of Li ions. Two phase transition temperatures, corresponding to TO-T and TC, were observed in the KNN-xL thick films. The sample with x = 0.06 exhibited an optimized value of d33 (91.6 pm/V), which was attributed to the formation of a morphotropic phase boundary.