Zirconium phosphonate

Kumar, C.V. and Chaudhari A. (2001) Efficient renaturation of immobilized met-hemoglobin at the galleries of alpha-zirconium phosphonate. Chemistry of Materials, 13, 238-240. 

Fig. 42.10 Ligands anchored to zirconium phosphonate-layered structures or titanium dioxide particles.

Layered metal IV phosphonates are widely used, particularly zirconium phosphonates, because their synthesis is versatile and their structural arrangement may be tailored to applications. Zirconium phosphonates are usually prepared by heating an aqueous solution of a metal IV salt (e.g., ZrOCl2) with a phosphonic acid at 60-80 °C synthesis in the presence of HP permits one to increase significantly the crystallinity of the final products. 

Molecular Design of Two-Dimensional Zirconium Phosphonate Catalysts... 

Preparation and characterization of two-dimensional zirconium phosphonate derivatives in either crystalline or amorphous forms have been investigated. Two composite zirconium phosphonates in single crystal phase have also been investigated and characterized by XRD, i c-, and 3ip-MASNMR. The catalytic performance over zirconium phosphonates are evaluated by hydrolysis of ethylacetate in aqueous solution. When the composite zirconium phosphonate is composed with an acidic function and with a hydrophobic function in single crystal phase, the catalytic activity in aqueous medium showed higher activity than that of single acidic zirconium phosphonate. The composite materials become accessible to any reactant molecule and improve hydnq>hobicity. 

This work is aimed at establishing a preparation procedure for zirconium phosphonates not only in the single component phosphonate but also in the composite zirconium phosphonates in single crystal phase, and to establish a procedure to characterize these compounds. 

Zirconium phosphonates are solid materials typically synthesized in amorphous forms under aqueous conditions by the reaction of a soluble salt of a tetravalent metal and a phosphonic acid or an organophosphoric acid ... 

TABLE 1 Physico-Chemical Properties of Various Crystalline Zirconium Phosphonates... 

The acidic function of single zirconium phosphonate showed rather poor catalytic activities for hydrolysis of ethylacetate in aqueous solutions. In addition, over Zr(03PCH2S03H)2 catalyst, the reaction proceeds as a homogeneous reaction, even though the catalytic activity is higher than other acidic zirconium phosphonates. The objective of this study is to explore the role of a second phosphonate function in single crystal phase on the catalytic performance of acidic function and hydrophobic function of zirconium phosphonates and to learn how to exploit this second function to achieve a catalytic advantage in certain applications. 

Formation of SA monolayers of phospholipids [217,242] and surface-active viologens [244, 245] on gold substrates, those of long-chain zirconium-phosphonates on silicon substrates [243], and those of alkanethiols on gallium arsenide substrates [246] have also been reported. 

Layered zirconium phosphate and zirconium phosphonates Size-quantized ZnSe, PbS, CdS, and CdSe grown in the interlamellar region of layered zirconium hosts... 

Amide and ester derivatives of zirconium phosphonate have been prepared via amine and alcohol intercalation and subsequent condensation reactions [28], X-ray diffraction patterns and spectroscopic measurements show that the inter-... 

More recently, crown ether pillared and functionalized a-zirconium phosphonates have been synthesized [34], Incorporation of crown ethers was achieved by first converting them to their respective phosphonic acids. X-ray diffraction studies showed that the interlamellar spacing was about 15 A when a biphospho-nic acid was used. Both a- and y-type zirconium phosphonates could be synthesized using this methodology. Preliminary results showed that these layered materials have good selectivity toward binding transition metal ions and that the interlamellar fluoride ions could be replaced by anion exchange. 

Bellezza F, Cipiciani A, Costantino U, Nicolis S (2004) Catalytic activity of myoglobin immobilized on zirconium phosphonates. Langmuir 20 5019-5025... 

Zhang B. and Clearfield A., Crown ether pillared and functionalized layered zirconium phosphonates a new strategy to synthesize novel ion selective materials, J. Am. Chem. Soc. 119(1997) pp. 2751-2752. 

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