Improvement in synthesis of (K_0.5Na_0.5)NbO₃ powders by Ge⁴⁺ acceptor doping

Abstract

In this paper, the effects of doping with GeO₂ on the synthesis temperature, phase structure and morphology of (K_0.5Na_0.5)NbO₃ (KNN) ceramic powders were studied using XRD and SEM. The results show that KNN powders with good crystallinity and compositional homogeneity can be obtained after calcination at up to 900°C for 2 h. Introducing 0.5 mol.% GeO₂ into the starting mixture improved the synthesis of the KNN powders and allowed the calcination temperature to be decreased to 800°C, which can be ascribed to the formation of the liquid phase during the synthesis.

Keywords

lead-free piezoelectrics / potassium sodium niobate / synthesis / acceptor doping

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