Ferroelectric and piezoelectric properties of lead-free (K,Na,Li)(Nb,Ta,Sb)O3 ceramics fabricated by using a citric-acid-assisted modified sol-gel method

We fabricated lead-free (K 0.44 Na 0.52 Li 0.04 )(Nb 0.86 Ta 0.10 Sb 0.04 )O 3 (LF4) ceramics by using a citric-acid-assisted modified (CAM) sol-gel method. The CAM sol-gel method is based on a solution approach, which ensures a uniform distribution and atomic-level mixing of the reactants and the gelling agents. The optimized calcination temperature for the LF4 ceramics fabricated by using the CAM sol-gel method was about 200 °C lower than that for ceramics fabricated using the solid-state reaction method. The LF4 ceramics had better ferroelectric and piezoelectric properties than those produced using the solid-state reaction method.