Eletrocatalisadores suportados em quitosana para a reação de eletro-oxidação de metanol

Abstract

Most of the world's energy needs are currently met by burning fossil fuels in low-efficiency thermal processes. Based on these aspects, a promising alternative for energy production is fuel cells. Direct Methanol Fuel Cells (DMFC) are considered as an alternative and promising energy source for use in mobile and stationary systems. The present work used methanol as fuel, evaluating the electro-oxidation of alcohol using PtRu/Q, Pt/Q, PtRu/C and Pt/C electrocatalysts. Therefore, the catalysts were prepared via MAF (Formic Acid Method). The electrochemical behavior of the electrocatalysts was verified using cyclic voltammetry (VC) and chronoamperometry (CA) techniques in an acidic medium. The tests were carried out in four stages: VC of the working electrode (Au), VC of the electrocatalysts, VC of the methanol electro-oxidation and CA of the methanol oxidation at a fixed potential for 1800 seconds. Against the results, among the PtRu/Q, Pt/Q, PtRu/C and Pt/C catalysts, the Pt/Q and Pt/C catalyst was the one that showed the best performance in catalytic activity in an acidic medium in the absence and presence of alcohol. In the stability test carried out using the chronoamperometry technique with a time of 1800 s, it was found that the Pt/Q metallic catalyst obtained the highest current value at the end of the test, 0.28 µA.cm-2.