Tailoring cathode structure of catalyst coated membranes for performance enhancement in direct methanol fuel cells

Abstract

In this study, we demonstrate how the formulation of colloidal catalyst ink and fabrication conditions affect the cathode microstructure of catalyst coated membranes (CCMs) prepared via decal technique. The CCMs based on conventional and high concentration cathode inks are compared in a direct methanol fuel cell (DMFC). It is found that the cathode catalyst layer made with a high concentration ink possesses superior porosity, leading to an improved DMFC performance. The temperature of roll-press used for preparing CCM is varied ranging from 170 to 210 degrees C in order to determine the optimal fabrication conditions for high concentration ink-based cathode. The CCM hot-pressed at 200 degrees C (advanced CCM) retains a significantly higher pore volume and outperforms' the conventional CCM by delivering an excellent DMFC performance with a maximum power density of 155 mW cm(-2), which is 20% higher than that of the conventional CCM. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.