Impact of Highly Stable Catalyst Support Materials on Polymer Electrolyte Membrane Fuel Cell Performance

Abstract

Durability of catalyst support materials is one of the big challenges for long‐term fuel cell operation. The performance stabilities of stabilized carbons as cathode catalyst supports for polymer electrolyte membrane fuel cells (PEMFCs) are investigated. Homemade platinum (Pt) electrocatalysts are prepared on stabilized carbons and a traditional carbon black support. Subsequently, the characterization results of homemade catalysts are compared with a commercial catalyst. The characterization tools such as the measurement of electrochemical active surface areas (ECSAs), oxygen reduction reaction (ORR) activities, durability of both the Pt and the supports, and eventually membrane electrode assembly (MEA) single cell tests are implemented herein. The stabilized carbon supported catalysts show comparable ORR activities as well as improved corrosion resistance in terms of ECSA survival rates under accelerated stress conditions compared with the conventional supported catalysts. In addition, the dependency of MEA performances on the ionomer‐to‐carbon ratio on the catalyst layers is established.

Effects of Supports BET Surface Areas on Membrane Electrode Assembly Performance at High Current Loads

“…Additionally, oxidation of the super C 65 support increased the BET surface area from 62 to 174 m 2 g −1 . The change of surface properties of the support materials was due to introduction of some surface functional groups to the carbon support that was previously confirmed via Böhm titration [17]. Nevertheless, the BET surface areas, electronic conductivity, and hydrophilicity of oxidized super C65 were still lower than the traditional Vulcan XC72 (CB) material as shown in Table 1.…”

“…In fuel cells, uniformly dispersed Pt nanoparticles on support materials are highly desired in order to increase the ORR kinetics as well as Pt utilization. Homogeneous Ptparticle distribution of the homemade catalysts by comparison of X-ray Powder Diffraction (XRD) data and Transmission Electron Microscope (TEM) measurements was already shown elsewhere [45].…”

“…Unfortunately, most of the reported highly ORR active stable catalysts were either not transferable to membrane electrode assembly (MEA) or did not meet the expectation in real-time fuel cell operation. In our previous work, CB materials prepared by a silica template process showed promising properties as support materials in terms of both stabilities and activities for fuel cell applications [17]. However, the preparation of a highly Pt-nanoparticle-loaded catalyst is still challenging due to the low-BET surface areas of those support materials.…”

Impact of Membrane Types and Catalyst Layers Composition on Performance of Polymer Electrolyte Membrane Fuel Cells

“…Thus, optimization of the ionomer film in each CL is needed to achieve maximum MEA performance. The optimum ionomer content is depending on the Brunauer, Emmett, and Teller (BET) surface areas of the support materials . Unfortunately, there are no experimental techniques available, except the performance characterization of MEA in a full cell to determine the optimum amount of ionomer needed for each CL.…”

Effects of Endplate Assembly on Cold Start Performance of Proton Exchange Membrane Fuel Cell Stacks

“…The focus has been placed on the visualization of ice formation, [11][12][13] optimization of loading strategy, [14] and analysis of starting-up conditions, [15][16][17] flow-field design, [18,19] and tailoring of fuel cell materials. [20][21][22][23][24][25] Cold start models have also been developed for single cells and stacks to gain a better understanding of the start-up process. [26][27][28] A PEMFC stack has two endplate assemblies (EAs) to stabilize the multilayered structure and distribute the preload evenly on each cell.…”