Study of variations of physico-chemical properties of Nd-Pt/C and Pt-Nd-Sn/C for the ethanol electro-oxidation.

Abstract

In general, in order to develop efficient catalysts for ethanol oxidation reaction in direct ethanol fuel cells (DEFC) is necessary to understand the influence of physical and chemical properties of materials in catalytic activity, elucidate the reaction mechanism and evaluate the unit cell performance. Therefore, this research project involves the preparation of carbon-supported catalysts based on Pt, Nd and/or Sn by polyol and formic acid reduction methods. After syntheses, these catalysts will be coated with a protective layer of MgO and annealed in high temperatures with different atmospheres: inert and reductive. MgO - protector agent - is used in thermal treatment in order to change the alloy/oxide composition de Pt-Sn and/or Nd with no significant changes in the particles size. In addition, by using different temperatures in the thermal treatment process, it is possible to control the crystallinity of the catalysts, which will allow a better understanding of the relation between the alloy/oxide composition of the material and their catalytic activity in ethanol oxidation. The catalysts will be characterize physically by DRX, EDX, TEM, XPS and XAS, electrochemically by voltammetry and chronoamperometry. The performance of materials will be in the unit cell and evaluation of products and intermediaries of the ethanol oxidation reaction by HPLC and/or FTIRAS. Finally, we intend to correlate physical and chemical properties of the catalysts with their efficiency in ethanol oxidation reactions.