Oxovanadium phosphate

FIGURE 12.15 Schematic representation of thd IS cooperative formation mechanism for ICMUV-2 mesostructured oxovanadium phosphates. (Reprinted from El Haskouri J., M. Roca, S. Cabrera, J. Alamo, A. Beltran-Porter, D. Beltran-Porter, M.D. Marcos, and P. Amoros. 10SH m. Mater. 11 1446-1454. With permission from American Chemical Society.)... 

The interface between organic and inorganic substructures has been manipulated in the preparation of hybrid materials which exhibit composite or even new properties, representative examples of which include zeolites [34-36], mesoporous oxides of the MCM-41 class [37] and metal phosphates with entrained organic cations [38-55] (Refs 39-55 are representative examples of the expanding family of oxovanadium-phosphate-organic cation materials). 

Zubieta J., Clusters and solid phases of the oxovanadium-phosphate and -organophosphonate systems, Comments Inorg. Chem. 16 (1994) pp. 153-183. 

VI. OXOVANADIUM PHOSPHATES AND ORGANOPHOSPHONATES WITH SECONDARY META-LIGAND SUBUNITS INTEGRATED INTO COVALENTLY LINKED V/O/M /P SCAFFOLDINGS... 

B. Influence of M -Organodiimine Subunits on Oxovanadium Phosphate Structures... 

The oxovanadium phosphate system represents an important subclass of the family of inorganic phosphates. The dramatic expansion of the chemistry of... 

VI. Oxovanadium Phosphates and Organophosphonates with Secondary Metal-Ligand Suhunits Integrated into Covalently Linked V/O/M /P Scaffoldings... 

Oxovanadium phosphate VOPO4.2H2O is used as a catalyst, or catalyst precursor. It is a layered compound in which six oxygen atoms around the vanadium form an almost regular octahedron. The weaker interlayer binding makes VOPO4.H2O and its analogs attractive as potential hosts for coordination—intercalation reactions [5—11]. 

The oxovanadium phosphates constitute a subclass of the general family of metal oxides, which display important catalytic properties and a remarkable structural diversity. The syntheses selected for this volume do no reflect a comprehensive attempt to provide the most important representatives of oxovanadium phosphates that have been described since the late 1990s. Rather, the focus is on the critical role of the organic component as a structure-directing agent and on the efficacy of the hydrothermal technique for the isolation of crystalline metastable phases. 

The two oxovanadium phosphate phases and the oxovanadium phosphite material whose syntheses are described contain alkyldiammonium cations whose presence is essential to the isolation of the products. The structures of these materials, which are represented schematically in Figs. 1-3, reveal the importance of hydrophobic/hydrophilic interactions and multipoint hydrogen bonding. 

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