Three sandglass-type molybdophosphates obtained via a new route: Synthesis and characterization of X7[PMo8O30] (X=Na+, K+, NH4+)

✍ Scribed by Yan-Chun Bai; Li-Ping Liu; Xing-Juan Yan; Wei Chu; Ying-Ying Zhu; Yu-Ting Song; Ru-Dan Huang

• Book ID: 104030257
• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 759 KB
• Volume: 182
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1016/j.jssc.2008.09.025

✦ Synopsis

Three new polyoxometalates X 7 [PMo 8 O 30 ] (X ¼ Na + , 1; K + , 2; NH 4 + , 3) have been synthesized with the classical Keggin and/or Dawson heteropolymolybdophosphates and PCl 5 in acetonitrile-water solutions via hydrothermal treatment. The three compounds were characterized by different analyses including IR, 31 P NMR spectroscopy, elemental analysis, electrochemistry, thermogravimetric analysis (TGA) and powder X-ray diffraction (XRD). Single crystal X-ray analyses were carried out on Na 7 [PMo 8 O 30 ] (1) and (NH 4 ) 7 [PMo 8 O 30 ] (3). Compound 1 and 3 crystallize in the orthorhombic system. The structure of compound 2 was confirmed by the IR spectra and powder XRD. All the three compounds contain the same octamolybdophosphate polyoxoanion [PMo 8 O 30 ] 7À , which consists of two Mo 4 O 15 moieties linked by one central PO 4 tetrahedron, leading to a remarkable sandglass-like structure.