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- Carbon nanotube supported catalyst is a novel supported catalyst, using carbon nanotubes as the support instead of the conventional alumina or silicon support. The exceptional physical properties of carbon nanotubes (CNTs) such as large specific surface areas, excellent electron conductivity incorporated with the good chemical inertness, and relatively high oxidation stability makes it a promising support material for heterogeneous catalysis. The catalyst is a substance, usually used in small amounts relative to the reactants, that increases the rate of a chemical reaction without itself undergoing any permanent chemical change. One or more kinds of catalysts can be loaded on another material with a high surface area, which serves as the support, to form a supported catalyst as a whole system. In a supported catalyst system, the significance of using the support are to increase the dispersion of the active phases, to have a better control of the porous structure, to improve mechanical strength, to prevent sintering and to assist catalysis. There is a wide spectrum of supports ranging from conventional and most commonly alumina to novel various kinds of activated carbon. Synthesis methods and functions vary greatly due to different kinds of support and catalytic materials. The challenge in making a supported nanoparticulate catalyst is to avoid agglomeration. This can be achieved by using a poly-functional anchoring agent, and drying under a relatively low temperature. Relative research are deposition of palladium and platinum particles on activated carbon, using a poly-acrylate anchor. To unveil more molecular details of the extensive interactions between precursors and supports in an aqueous environment, studies of adsorption and precipitation chemistry must be taken into account. Progress is being made in the use of chemical vapor deposition for the synthesis of supported catalysts. Combinatorial techniques have seen their contributions to solid catalyst synthesis. (en)
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