Metallic Catalysts Supported on Amorphous Materials

Many practical catalysts consist of one or several active components, deposited on a high surface area support, whose purpose is the dispersion of the catalytically active component or components and their stabilization against sintering. In some cases, the support is passive in other cases, the support is not inert it is also part of the catalyst, combining oth functions, that is, the support and the active catalytic phases [56], 

We focus here on supported metallic catalysts, since metals are widely used as catalysts. However, the metal catalyst is often expensive. Then, it is usually applied in a finely dispersed form on a high surface area support, since in this circumstance, a large fraction of the metal atoms are exposed to the reactant molecules. 

In heterogeneous catalysis, transition metal nanoparticles are supported on different substrates and are utilized as catalysts for different reactions [57], such as hydrogenations and enantioselective synthesis of organic compounds [58], oxidations and epoxidations [59], and reduction and decomposition [57], 

The Physical Chemistry of Materials Energy and Environmental Applications 

Among the supports that have been used in the preparation of supported transition metal nanoparticles are carbon, silica, alumina, titanium dioxide, and polymeric supports [57], and the most frequently used support is alumina [56], These supports normally produce an effect on the catalytic activity of the metallic nanoparticles supported on the amorphous material [60], In Chapter 3, different methods for the preparation of metallic catalysts supported on amorphous solids were described [61-71], 

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