Intercalation zirconium phosphate

Figure 5. (a) Emission spectra (A.exc = 436 nm) of Mo2(dmhp)4 (dmhp = 4,6-dimethyl-2-hydroxypyrimidine) in (o) methanol, and HCl-acidified methanol with (i) 1-, (ii) 2-, (iii) 3-, and (iv) 4-equivalents of HC1 per equivalent of metal complex, (b) Emission spectra (Xexc = 436 nm) of (v) terf-octylamine-intercalated zirconium phosphate and (vi) ethanolic preswelled zirconium phosphate treated with Mo2(dmhp>4. Traces (o) - (v) show relative emission intensities and traces (v) and (vi) are arbritrary and unrelated to each other. 

Inspired by the separation ability of cyclic selectors such as cyclodextrins and crown ethers, Malouk s group studied the synthesis of chiral cyclophanes and their intercalation by cation exchange into a lamellar solid acid, a-zirconium phosphate aiming at the preparation of separation media based on solid inorganic-organic conjugates for simple single-plate batch enantioseparations [77-80]. 

An example of the modular preparation of the cyclophane 3 from the substituted bipyridine 2 and a general tripeptide 1 is shown in Scheme 3-3. The host molecule 3 contains a pre-organized binding pocket. The overall basicity of such molecules also facilitates their intercalation within the lamellas of acidic zirconium phosphate, thus making this chemistry well suited for the desired application. 

Fig. 1.19 Intercalation of enzymes at the galleries of layered a-zirconium phosphate following a delamination-restacking mechanism.

Kaschak, D.M., Jhonson, S.A., Hooks, D.E., Kim, H.-N., Ward, M.D. and Mallouk, T.E. (1998) Chemistry on the edge A microscopic analysis of the intercalation exfoliation, edge functionalization and monolayer surface tiling reactions of alpha-zirconium phosphate. Journal of the American Chemical Society, 120, 10887-10894. 

LiNa Geng et al. realized similar experiments for the adsorption of trypsin [141] and hemoglobin [142] on y-zirconium phosphate (y-ZrP) and organo y-ZrP intercalated with butylammonium (BA) and tetrabutylammonium (TBA). Hb adsorbed in the galleries of BA-y-ZrP and TBA-y-ZrP mainly by hydrophobic... 

Figure 3. Three basic strategies for the incorporation of multiply bonded metal-metal guest species into vanadyl and zirconium phosphate host layers, (a) The direct intercalation of solvated M—— M cores into the native layered phosphate host structure, (b) Incorporation of M—— M complexes with ancillary ligands containing a Lewis basic site, (c) Coordination of M—— M cores with ligands provided from modified phosphate layers.

M. E. Nino, S. A. Giraldo, E. A. Paez-Mozo, Olefin oxidation with dioxygen catalyzed by porphyrins and phthalocyanines intercalated in /-zirconium phosphate, J. Mol. Catal. A Chem. 175 (2001) 139. 

Zirconium phosphates have been extensively investigated as intercalation hosts (531. and the catalytic properties of some pillared zirconium phosphates has been reviewed by Clearfield (541. 

A large number of inorganic layer crystals such as micas, sodium silicates, niobate, uranate, vanadate, titanate, zirconium phosphate, graphitic acids, crystalline silicic acids, vanadium oxyhydrate, calcium phosphoric acid esters, and titanium disulfide develop alkyl crystals between their rigid crystal layers by ion exchange with, for example, alkyl ammonium salts and by intercalation inorganic... 

Zirconium phosphate, besides the traditional intercalation processes, has been used to produce pillared compounds, such as those involving mixed Fe-Cr oxides [3]. Furthermore, it has been shown [4] that the protonic conductivity of a-zirconium phosphate can be enhanced by the formation of a composite with alumina or silica, an example of synergic cooperation between the oxides and phosphates which are the main classes of compounds highhghted in the book. 

The intercalation of PANI in zirconium phosphate (ZrP) was also reported by Chang et al. [69]. Different phases of zirconium phosphate, such as y-ZrP, the dihydrogen form of a-ZrP [o -ZrP(HH)], and o -ZrP(NaNa), were intercalated with aniline by either ion-exchange or adsorption, and then polymerized by oxidizing agents such as ammonium peroxydisulfate and iron (III) chloride. The resulting polyaniline nanocomposites showed measurable electrical conductivities, as listed in Table 6.3. 

Chang et al. also reported on the intercalation of aniline into zirconium phosphate sulfophenylphosphonate (ZPS), an organo derivative of a-zirconium phosphate [70]. The hydrophilic (—SO3H) groups in ZPS promote swelling of ZPS, which served as a template for aniline. The aniline-ZPS system was then oxidized with ammonium peroxydisulfate to yield a polyaniline-ZPS composite. However, there is no X-ray evidence that has been provided to support the formation of an intercalated phase. 

T. Chang, S. Ho, and K. Chao, Polyaniline intercalated into zeolites, zirconium phosphate and zirconium arsenate, J. Phys. Org. Chem., 7, 371-376 (1994). 

These layered phosphates do not swell in water. Therefore, the layers were first spread apart by intercalation of butylamine. In this condition the AI13 species was exchanged for the alkylammonium ion to form pillared products [19]. Table 12-1 gives a summary of some of the results obtained with zirconium phosphate. It is observed that the surface areas of the aluminum... 

Figure 13-4. Co2p spectra of cobalt-phen complexes intercalated in a-zirconium phosphate compared with those of Co(OH) and [Co(phen) ]Cl ...

Layered a-zirconium phosphate and its modified and intercalated phases... 

The lamellar sheet-like structure of amine-intercalated Zr(HP04)2 can be delaminated to give thin films of pellicular hydrated zirconium phosphate. These will adhere to flat surfaces and are stable to solvents and temperatures up to 300-400°C. Pellicular forms are good proton conductors and have potential applications in ion exchange and chromatography. 

Figure 5. It is likely that the intercalated alkali cations are surrounded by ethereal oxygen atoms like the cations in crown ethers, the iodine and thiocyanate anions being associated with the cations. It is interesting to note that the organic derivatives of y-zirconium phosphate synthesized in this study can form the complexes only with the alkali salts having soft base anions such as I and SCN , but not with the salts having hard base anions such as Br and N03 .

A previous paper [1] reported on the usefulness of the spectral subtraction technique in analysing the infrared spectra of clathrates formed by quinol and by Dianin s compound. Here we report on the use of the technique in analysing the infrared spectra of some intercalates of zirconium phosphate, and the Raman spectra of some clathrates of quinol. 

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