Low Temperature Sintering and Enhanced Piezoelectricity of Lead-Free (Na0.52K0.4425Li0.0375)(Nb0.86Ta0.06Sb0.08)O3 Ceramics Prepared from Nano-Powders



(Na0.52K0.4425Li0.0375)(Nb0.86Ta0.06Sb0.08)O3 powders were synthesized via sol–gel and solid-state reaction methods as a raw material for the preparation of the ceramics. Dependence of piezoelectric properties and microstructure on sintering temperatures was investigated in this study. Sol–gel-derived nano-powders could be densified at a lower temperature of 940°C and exhibited excellent electrical properties after sintering at 1020°C (d33 = 424 pC/N, d33* = 780 pm/V, kp = 52.1%, and Tc = 265°C). The enhanced electric properties were most likely due to the coexistence of orthorhombic and tetragonal phase in the samples at room temperature, homogenous microstructure with fine grain and high density.