Aerogel synthesis methods

In this chapter, the aerogel synthesis method is detailed and recent catalytic examples, from 1999 up, will be presented and discussed. Because of their potentialities, ambigels, which do not require the use of an autoclave, are also briefly described. 

In this chapter, we focus on the importance of nanoarchitecture in determining the electrochemical properties of transition metal oxide aerogels. After a brief introduction to aerogels and their synthesis methods we give an overview of the electrochemical characterization techniques employed when dealing with nanostructures. This chapter concludes with a case study on how aerogel nanostructures have improved the electrochemical properties of vanadium pentoxide. 

It seems that new opportunities exist in aerogel synthesis, taking advantage of both the ambigel method and the direct sol-gel chemistry under supercritical conditions. It is likely that these new methods could be of a great potential interest for scientists involved in the preparation of catalytic materials. 

Although the present review is mainly focused on one-step synthesis methods, the two-steps method, which consists in preparing a xerogel or aerogel support which will be next loaded with one or several metal(s) processor(s), is briefly presented below. 

An alternate approach to chalcogenide aerogel synthesis is to start with discrete nanoparticles of metal chalcogenides and condense them together to form a gel network. A method for doing just that was reported in 1997 by Gacoin and coworkers [21-25]. 

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