Encapsulation of two Potassium Cations in Preyssler-type Phosphotungstates: Preparation, Structural Characterization, Thermal Stability, Activity as an Acid Catalyst, and HAADF-STEM images
Encapsulation of two Potassium Cations in Preyssler-type Phosphotungstates: Preparation, Structural Characterization, Thermal Stability, Activity as an Acid Catalyst, and HAADF-STEM images
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Preyssler 型磷钨酸盐中两种钾阳离子的封装：制备、结构表征、热稳定性、酸催化剂活性和 HAADF-STEM 图像
DOI：
10.1021/acs.inorgchem.6b02116
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发表时间：
2016
期刊：
影响因子：
4.6
通讯作者：
Masahiro Sadakane
中科院分区：
文献类型：
--
作者：
Akio Hayashi;Hiromi Ota;Xavier Lopez;Norihito Hiyoshi;Nao Tsunoji;Tsuneji Sano;Masahiro Sadakane
在过量钾离子存在的情况下，通过在醋酸盐缓冲液中加热包覆有Bi3+的Preyssler型磷钨酸盐[P5W30O110Bi(H2O)]12-，制备了包裹有二钾离子(K+)的Preyssler型磷钨酸盐[P5W30O110K2]13-。通过单晶X-射线结构分析、31P和183W核磁共振、傅立叶变换红外光谱、循环伏安、高分辨电喷雾电离质谱仪和元素分析，表征了分离的钾盐K13[P5W30O110K2](1a)和酸形式H13[P5W30O110K2](1b)，这是第一个具有两个阳离子的Preyssler型磷钨酸盐分子中含有两个阳离子的例子。两种钾阳离子的引入提高了钾盐的热稳定性，酸性形式对乙酸乙酯的水合反应具有催化活性。用高分辨率高角环形暗场扫描电子显微镜(HAADF-STEM)观察了Preyssler类分子的堆积。
Dipotassium cation (K+)-encapsulated Preyssler-type phosphotungstate, [P5W30O110K2]13-, was prepared by heating monobismuth (Bi3+)-encapsulated Preyssler-type phosphotungstate, [P5W30O110Bi(H2O)]12-, in acetate buffer in the presence of an excess amount of potassium cations. Characterization of the isolated potassium salt, K13[P5W30O110K2] (1a), and its acid form, H13[P5W30O110K2] (1b), by single crystal X-ray structure analysis,31P and183W nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR) spectroscopy, cyclic voltammetry (CV), high-resolution electrospray ionization mass spectroscopy (HR-ESI-MS), and elemental analysis revealed that two potassium cations are encapsulated in the Preyssler-type phosphotungstate molecule with formalD5hsymmetry, which is the first example of a Preyssler-type compound with two encapsulated cations. Incorporation of two potassium cations enhances the thermal stability of the potassium salt, and the acid form shows catalytic activity for hydration of ethyl acetate. Packing of the Preyssler-type molecules was observed by high-resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM).