Composite Catalysts

A thin layer of the catalytically active metal phase is present on the support surface of composites, which are catalysts. The pattern of metal distribution seen on these supports resembles an egg-shell-like shape. For reactions that have difficulty transferring mass or heat, this distribution is ideal. Gold, platinum, and osmium were among the metals that were deposited atop silver sulphide nanocrystals to create the nanocomposite (pictured). It is feasible to adjust the catalytic characteristics of the finished composite by successively depositing different metals onto the nanocrystal surface. methanol fuel cell, an electrochemical device that breaks down methanol to create energy, and the catalytic efficacy of its platinum-containing nanocomposites. Methanol is catalytically transformed into carbon dioxide at the anode side of the fuel cell by a process known as the methanol oxidation reaction (MOR), which also liberates hydrogen and electrons. Before recombining with the hydrogen and oxygen in an oxygen reduction process (ORR) at the cathode, the electrons travel through an electrical circuit, creating water as a byproduct. The increased surface area of the platinum deposits on the nanocrystals, which gives the MOR a bigger electrochemically active surface, as well as the improved electronic characteristics of the nanocomposite itself, are responsible for the extraordinary catalytic performance of the anodes. This keeps the catalyst from becoming "poisoned" by carbon monoxide, an intermediate in the MOR, clinging to the platinum.