1 Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, SDU2 Department of Physics, Chemistry and Pharmacy, Faculty of Science, SDU3 NanoMaterials Group, Department of Applied Physics, Aalto University4 IRD Fuel Cells5 VTT Technical Research Centre of Finland, Tampere, Finland6 CIDETEC-IK4-Centre for Electrochemical Technologies, Paseo Miramón 196, E-20009 Donostia-San Sebastián, Spain7 Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, SDU
Durability issues have recently been given much attention in Proton Exchange Membrane Fuel Cell (PEMFC) research. It gives fundamental definition for cell life time, capital cost, system stability and technique reliability. Loss of catalyst surface area due to corrosion of supporting material (normally carbon black) is one of the essential degradation mechanisms during cell operation. In this work, durability of Carbon Nanofibers (CNF) & Carbon Nanotubes (CNT) as alternative platinum catalyst supports for Proton Exchange Membrane Fuel Cells (PEMFCs) was assessed. Platinized CNF and CNT using a standard polyol method were prepared and fabricated as cathodes of Membrane Electrode Assemblies (MEA) for PEMFC. Both the catalysts as such and the MEAs made out of them were evaluated regarding to thermal and electrochemical stability using traditional carbon black (Vulcan XC72) as a reference. Thermal gravimetric analysis (TGA), cyclic voltammetry (CV), polarization curve and impedance spectroscopy were applied on the samples under accelerated stress conditions. The carbon nano-materials demonstrated better stability as support for nano-sized platinum catalyst under PEMFC related operating conditions. Due to different morphology of the nano carbons compared to Vulcan XC 72 the electrode structures may still need optimization to improve overall cell performance.