ABSTRACT
For a variety of reasons, silica and alumina structures are important frameworks for the subject of heterogeneous catalysis. Aluminas, and perhaps to a lesser extent silicas, are employed directly as cracking catalysts or as substrates for assorted catalytic systems. From the point of view of catalysis, structures at both the surface and in the interior (bulk properties) are important. This chapter focuses on surfaces. Because of nuclear magnetic resonance's (NMR) sensitivity to local structure and its forgiveness of long-range disorder, solid-state NMR is one of the methods of choice for studying the structures of these materials. The chapter emphasizes the surface characterization of silica and alumina systems and silica aluminas by NMR methods. Technical aspects highly relevant to surface characterization are explicitly discussed. The chapter is also concerned with dynamics at the surface.
