Two‐step Synthesis of Platelike Potassium Sodium Niobate Template Particles by Hydrothermal Method

Abstract

Two‐step hydrothermal synthesis of platelike potassium sodium niobate ( K , Na ) NbO 3 ( KNN ) template particles was investigated. Platelike K 4 Na 4 Nb 6 O 19 ·9 H 2 O ( KNN ‐hydrate) particles were synthesized in 4 mol/L aqueous alkali at 150°C by the sodium dodecyl benzene sulfonate ( SDBS ) surfactant‐assisted hydrothermal method, which were used as crystal nucleus in the second step of hydrothermal synthesis. The two‐step synthesized KNN ‐hydrate particles with 0.6 μm thickness and 7 μm width were prepared at 80°C after 10 h of the second step. After calcination of the KNN ‐hydrate particle at 600°C, platelike KNN particles were obtained, which were used as templates for textured ceramics. Particles obtained by the two‐step synthesis showed regular morphology and uniform distribution, with a marked improvement in grain size.