Organic functional groups, mesoporous

Organo-functionalized surface modified MCM-41 type mesoporous materials having various organic functional groups... 

Figure 3.7 Grafting (postsynthetic functionalization) for organic modification of mesoporous pure silica phases with terminal organotrialkoxysilanes of the type (R 0)3SiR. R = organic functional group.

Surface modification is possible by essentially all the reactions which have been developed over the past decades for amorphous silica. Excellent compilations of the different reagents and modifications achieved for ordered mesoporous silica are given in reviews by Anwander [4] and by Sayari and Hamoudi [5]. In almost all cases, trialkoxysilanes, trichlorosilanes, or disilazanes are used, which bear the organic functional group that is to be grafted to the surface of the silica. Also, several other review papers on surface modification with organosilicon groups are available [6 - 8]. 

Fig. 7. Two primary modes of organic (functional) group distribution in mesoporous frameworks. ...

Huh, S. Wiench, J. W Trewyn, B. G. Song, S. Pruski, M. Lin, V. S. Y, Tuning of particle morphology and pore properties in mesoporous sihcas with multiple organic functional groups. Chemical Communications (18), 2364—2365, 2003. 

To modify the mesoporous materials with organic functional groups, the two major methods of co-condensation and grafting are usually used. In the co-condensation method, a silica source containing an organic functional group is mixed with a conventional silica source, such as tetraethyl orthosilicate. 

Recently, organic moiety-functionalized mesoporous materials could be introduced onto the internal pore surfaces through the direct design of organic functional groups targeted for a variety of applications such as catalysis, sensing, and separation. 

A. Walcarius and C. Delacote, Rate of Access to the Binding Sites in Organically Modified Silicates. 3. Effect of Structure and Density of Functional Groups in Mesoporous Solids Obtained by the Co-Condensation Route, Chem. Mater., 2003, 15, 4181. 

Organic Functionalized Mesoporous Materials and Site-Isolation of Functional Groups... 

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