Hydrothermal synthesis and characterization of KZr_2(AsO_4)_3

摘要

Since the discovery of the ionic conductivity of the so-called NASICON phases (Na super ionic conductor, NaZr_2Si_2PO_(12)), NASICON and its structurally related compounds have been extensively studied [1]. These compounds have also been found to exhibit low thermal expansion and are envisaged as materials for nuclear waste storage and in thermal shock resistance applications [2]. KZr_2 (AsO_4)_3 is the parent phase of this large family. The flexibility of these structures allows chemical substitution and gives rise to a large number of isostructural phases. These compounds are usually synthesized by solid state reactions. It is, however, difficulty to obtain pure phases and single crystals. Hydrothermal methods find increasing applications in materials science. They are technically important, both as a method of crystal growth and for the synthesis of pure materials with useful properties [3]. KZr_3(AsO_4)_3 has been synthesized in three steps [4], which decreased the productivity rate and influenced the phase purity. In this letter we report a novel simple method, hydrothermal crystallization, for the synthesis of KZr_2(AsO_4)_3 with high yield.