Structural, dielectric and piezoelectric features of (Na0.52K0.44Li0.04)Nb0.87Sb0.08Ta0.05O3 ceramics

Abstract In this paper, two different processing routes were adopted for the preparation of lead-free (Na 0.52 K 0.44 Li 0.04 )Nb 0.87 Sb 0.08 Ta 0.05 O 3 ceramics and favorable results were obtained. The samples were characterized by X-ray techniques and scanning electron microscopy. Piezoelectric and dielectric data were presented. All the (Na 0.52 K 0.44 Li 0.04 )Nb 0.87 Sb 0.08 Ta 0.05 O 3 samples possessed pure perovskite phase, and not any secondary phase could be certified. Excellent piezoelectric properties of d 33  = 376pC/N, k p  = 44.1% and tan δ  = 2.4% were obtained for the composition compounded with (Na 0.52 K 0.44 Li 0.04 )NbO 3 and (Na 0.52 K 0.44 Li 0.04 )Nb 0.74 Sb 0.16 Ta 0.1 O 3 in the molar ratio 1:1. The remarkably strong piezoelectricity is probably due to the improved compositional homogeneity and enhanced densification achieved by the two-stage preparation method. The work will lead to further improvements in the properties of KNN-based piezoelectric materials.