Characterization of (K0.5Na0.5)NbO3 powders and ceramics prepared by a novel hybrid method of sol–gel and ultrasonic atomization

Abstract (K 0.5 Na 0.5 )NbO 3 powders and ceramics were prepared by a novel hybrid method of sol–gel and ultrasonic atomization, in which Nb 2 O 5 was used as the niobium source to replace those expensive soluble niobium salts. X-ray diffraction and thermal analysis were performed to investigate the synthesis process and phase transformation behavior of (K 0.5 Na 0.5 )NbO 3 powders. The results showed that (K 0.5 Na 0.5 )NbO 3 powders with a reasonably fine particle size and single-phase perovskite structure were formed at a temperature as low as 650 °C. Dense (K 0.5 Na 0.5 )NbO 3 ceramics with a relative density of 93% were obtained using the refined powders. The (K 0.5 Na 0.5 )NbO 3 ceramics prepared by the novel hybrid method exhibited relatively good properties ( d 33  = 90 pC/N, k p  = 0.32, P r  = 20.6 μC/cm 2 , T c  = 405 °C, e r  = 712), suggesting that this novel hybrid method might be a promising method for the powders and ceramics preparation.