Abstract
The alternative "clean" electricity generation has attracted attention of the academic and scientific world, targeting energy sources more efficient and less harmful to the environment.Several electrocatalysts using platinum and palladium in his compositions have been used for applications in direct alcohol fuel cells (DAFCs), but difficulties concerning the cost and quantity of the catalysts metals, low-power cell obtained, reduced efficiency in the C-C bonds breaking, and problems with the poisoning of the catalyst have limited this technology application for large-scale systems.It is proposed in this project, preparation and application of nano-structured electrocatalysts with new morphology such as core-shell bimetallic systems Pt- and Pd-based, seeking to promote the oxidation of ethanol, ethylene glycol, and glycerol, which are alternative fuels sources to methanol. It will be synthesized core-shell bimetallic systems M@Pt and M@Pd, (M = Ru, Sn or Ni) supported on high surface carbon area (Carbon Vulcan) and carbon nanotubes (CNT's), by three different methods: i) polyol employing the sequential process, ii) a sequential process of metal deposition, iii) chemical synthesis using the oxidation/reduction reactions.The physical characterization of nanocatalysts will be held through the techniques of Transmission Electron Microscopy (TEM), Energy Dispersive X-ray (EDX), X-ray Diffraction Spectroscopy (XRD), X-ray photoelectron (XPS) and High-Angle Annular Dark Field (HAADF). The electrochemical characterization will be performed using the techniques of cyclic voltammetry, chronoamperometry, chronopotentiometry, and the CO-stripping techniques, in order to estimate the electrochemically active area of the nanocatalysts. During the controlled potential electrolysis application, it will be carried out analyzes of the products formed using High Performance Liquid Chromatography (HPLC), Gas Chromatography Mass Spectrometry (GC-MS). In situ infrared reflectance technique (FTIR) will also be performed to allow us to obtain the products adsorbed at the interface. Finally, unit cells test to evaluate the electrocatalysts performance, durability and, stability will be performed.
|