Desenvolvimento de eletrocatalisadores a base de PtSn/C para utilização como eletrodo anódico em células a combustível de etanol direto

Abstract

The increase of energy demand has become a global issue, since the energy production is primarily based on the consumption of non-renewable fuels, causing several environmental damages. In this sense, fuel cells are considered great candidates to supply part of the world energy demand, since they produce electricity more environmentally friendly and efficient way, with practically no emission of toxic substances or pollutants. For the improvement of these devices, it is essential to study anodic electrocatalysts, which are responsible to the oxidation of the fuel, generating protons and electrons. In this work, electrocatalysts base on PtSn/C were synthesized in different Pt:Sn atomic ratio, by using borohydride reduction method, which enables the production of electrocatalysts with a narrow crystallite size distribution. The characterization of the resulting materials was carried out by X-ray diffraction (XRD). The electrochemical behavior of the electrocatalyst was evaluated by cyclic voltammetry in acidic solution and the electrocatalytic activity in front ethanol oxidation was studied by linear scan and chronoamperometry in acidic ethanol solution. The results show the effectiveness of the method used for the production of electrocatalysts active in front of ethanol oxidation reaction, since they generated significantly higher current density and lower onset oxidation potential as compared to commercial electrocatalysts, currently used.