Effect of flow rate, flow direction, and silica addition on the performance of membrane and the corrosion behavior of Pt-Ru/C catalyst in PEMFC

In order to evaluate the performance of Proton Exchange Membrane Fuel Cell (PEMFC) with an active area of 25 cm2, several variables were studied (flow pattern, flow rate, degradation in the Pt-Ru/C catalyst). Polarization curves revealed that the electrochemical reaction on both sides of the fuel cell is under the effect of mass transfer and the values of the cell voltage, current density, and power density were inversely proportional with the increase of the hydrogen and oxygen flow rates for both flow patterns (counter current and cocurrent) and clear corrosion phenomenon was observed on the surface of the Pt-Ru/C catalyst before and after exposure to the hydrogen and oxygen. On the other hand and in order to increase the performance of Nafion membrane, SiO2 particles were introduced to the Nafion polymeric matrix using sol-gel method to form composites. The surface morphology of the Nafion-SiO2 composite membrane was investigated and compared with the existing commercial Nafion membrane. It was found that water uptake of the Nafion- silica composite membrane as a function of temperature is higher than that of the existing commercial Nafion membrane.