Hydrothermal synthesis of sodium potassium niobate solid solutions at 200 °C

文献情報

出版日 2010-02-20

DOI 10.1039/B923840A

インパクトファクター 10.182

著者

Gregory K. L. Goh

原文を見る

要旨

For the first time, a series of sodium potassium niobate solid solutions with compositions around the morphotropic phase boundary (MPB) are hydrothermally synthesized at 200 °C using a simple KOH and NaOH mixture with Nb2O5 as a precursor powder. Rietveld refinement of X-ray diffraction data indicated the presence of a second sodium niobate perovskite phase when the concentration of NaOH (compared to the total hydroxyl ion concentration) is above 11.7%. The presence of the second phase is attributed to the different solubilities of the intermediate potassium and sodium hexaniobate species. It is also found that heat-treating the mixed-phase powders for two hours at a temperature of 800 °C is effective in obtaining the desired single-phase solid solution with compositions near the MPB, thereby opening the way to using hydrothermal synthesis in simplifying the laborious solid-state process.

掲載誌

Green Chemistry

CiteScore: 16.1

自己引用率: 7.5%

年間論文数: 944

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