Porous Oxides as a Function of Morphology

Mixed porous oxides can be divided into two main classes (similar to nanooxides) with mixed oxides synthesized simultaneously or matrix oxides (host oxides) modified by grafting of another oxide (guest oxide) using CVD, PVD, precipitation, or other methods. Clearly, the properties of the materials with the same gross composition but from different classes can be strongly different. Many of regularities found for mixed nanooxides can be true for porous oxides. However, the difference in the textural organization of these materials can play an important role, especially for 

FIGURE 2.68 (a) Relative NMR spin-eeho intensities versus temperature for cyclohexane confined within the pores of titania spherical particles (b) pore size distribution curves of the MTx samples determined by H NMR cryoporometry and BJH method (dashed fines) (c) insert with field-emission (FE) SEM image of MT400. (Adapted with permission from Ryu, S.-Y., Kim, D.S., Jeon, J.-D., and Kwak, S.-Y., Pore size distribution analysis of mesoporous TiOj spheres by H nuclear magnetic resonance (NMR) cryoporometry, J. Phys. Chem. C 114,17440-17445, 2010, Copyright 2010 American Chemical Society.) 

Nuclear Magnetic Resonance Studies of Interfacial Phenomena 

FIGURE 2.69 Ti and Ti MAS NMR spectra of anatase, brookite and rutile (chemical shift was estimated with respect to TiC4). (Adapted from Chem. Phys. Lett., 270, Labouriau, A. and Earl, W.L., Titanium solid-state NMR in anatase, brookite and rutile, 278-284, 1997, Copyright 1997, with permission from Elsevier.) 

Labouriau and Earl (1997) studied anatase, brookite, and rutile using the and MAS NMR 

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