Low Temperature Sintering and Enhanced Piezoelectricity of Lead‐Free ( Na 0.52 K 0.4425 Li 0.0375 )( Nb 0.86 Ta 0.06 Sb 0.08 ) O 3 Ceramics Prepared from Nano‐Powders

( Na 0.52 K 0.4425 Li 0.0375 )( Nb 0.86 Ta 0.06 Sb 0.08 ) O 3 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 ( d 33 = 424 pC/N, d 33 * = 780 pm/V, k p = 52.1%, and T c = 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.