ISSN:
1434-1948
Keywords:
Layered compounds
;
Zirconium
;
Amino acids
;
Zirconium L-(+)-serinephosphates
;
Intercalation
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A layered derivative of α-zirconium phosphate containing L-(+)-serine covalently attached to the inorganic layer has been prepared by allowing Zr fluoro complexes to decompose in the presence of L-(+)-phosphoserine. On the basis of thermogravimetric weight loss and C,H,N elemental analyses, the layered compound obtained has been formulated as Zr[HOOCCH(NH2)CH2OPO3]2. The X-ray powder diffraction pattern has been indexed with a monoclinic cell (a = 5.3737 Å, b = 9.3231 Å, c = 14.510 Å, β = 96.99°, Z = 2). FT-IR absorption spectra show that the serine groups attached to the inorganic layers are present as zwitterions. Thermal decomposition commences at ca. 250 °C and occurs in two steps: the first is due to a decarboxylation reaction, with the formation of the amino derivative Zr(NH2CH2CH2OPO3)2, while the second is associated with pyrolysis of the organic moiety, leading to ZrP2O7. Despite the presence of the amino acid function in the interlayer region, the compound does not show intercalation ability towards cations or anions or polar species. However, compounds with a certain degree of microporosity and possessing ion-exchange and adsorption properties have been obtained by replacing some of the phosphoserine groups of the compound by HPO4 groups, to produce the mixed layered derivatives Zr[HOOCCH(NH2)CH2OPO3]2-x-(HPO4)x.
Type of Medium:
Electronic Resource
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