Obtention of polymeric membrane fuel cells by low pressure plasma technique: Evaluation of total cell efficiency by function on the amount of platinum and the thickness of the deposited carbon support

This work aimed to obtain catalytic support over polymeric membrane building a fuel cell using low pressure plasma technique. For this, polymeric membranes were coated with carbon layer and platinum nanoparticles. The procedures were performed in separate steps in order to obtain firstly carbon layer and catalytic platinum nanoparticles. In the first step, the plasma processes were carried methane in order to obtain carbon layer over the polymeric membrane. At this stage, in order to obtain different thicknesses, were made several processes, reaching a thickness of 0.36μm to 1.4μm. The second step was to get the platinum nanoparticles on the carbon layer. For this, was used a platinum solid source and argon plasma. The study relied primarily on assessing the influence of the carbon layer on the performance of fuel cell. Compared with the commercial processes, it was observed that the results for fuel cells obtained by plasma have a better electric contact on three cell layers (catalyst - electrolyte - reagent). By electrochemical activity test was possible observe increase of reverse voltage of 0.8 volts to 1.24 volts according to increase the thickness of the carbon layer. The same behavior was also observed in the analysis of total efficiency, which was limited to 50% of maximum efficiency of commercial cell due the thickness of the carbon layer deposited during the preparation of this study, indicating a greater thickness with carbon it is possible to achieve the same efficiency of cells better than commercial. (paper)