Composite-supported Pt catalyst and electrosprayed cathode catalyst layer for polymer electrolyte membrane fuel cell

Abstract

Summary A major limitation of the conventional polymer electrolyte membrane fuel cell (PEMFC) catalysts is the fast oxidative degradation of their carbon black supports. Complete replacement of carbon black is difficult because of its low‐cost and high electrical conductivity. Reported here are the development and optimization of composite‐supported Pt catalysts and the electrosprayed cathode catalyst layer with these catalysts for PEMFC. These catalysts are supported by a composite of carbon black (Vulcan XC‐72R) and the electrochemically much more stable carbon‐embedded niobium‐doped titanium dioxide nanofibers (C/Nb0.1Ti0.9O2). Four different catalyst supports with 20 wt.% Pt were prepared by air spraying and electrospraying to compare their activity and stability. Vulcan XC‐72R and C/Nb0.1Ti0.9O2 were tested as pristine support materials for comparison as well as 1:3 and 3:1 mixtures by weight of the two pristine support materials (composite supports). The amount of Nafion in the catalyst ink was optimized for each catalyst layer by a volumetric method. An increase in carbon black content of the support layer from 0% to 100% increases the performance of these catalysts in H2/air PEMFCs but also increases the loss of oxygen reduction reaction mass activity. The best balance between PEMFC performance and durability was obtained for the Pt catalyst with 25% carbon black in the support layer, while the highest initial oxygen reduction reaction mass activity was obtained for the catalyst with 75% carbon black content. Copyright © 2017 John Wiley & Sons, Ltd.

Full Parametric Study of the Influence of Ionomer Content, Catalyst Loading and Catalyst Type on Oxygen and Ion Transport in PEM Fuel Cell Catalyst Layers

“…Efforts to increase the stability and durability of the catalyst layer are hence ongoing with one such effort focusing on the differences in structure between conventional and non-conventional catalyst layers [1]. Examples of non-conventional catalyst layers are dispersed catalyst layers, either on the membrane or the gas diffusion layer, ultrathin catalyst layers and nano-structured thin film (NSTF) catalyst layers [2][3][4][5][6]. Although much work is found on non-conventional catalyst layers, conventional layers are still at the forefront of research due to other challenges facing their non-conventional counterparts [1] and hence, the discussion within this manuscript is focused on conventional catalyst layers.…”

Electrospray Deposition: A Breakthrough Technique for Proton Exchange Membrane Fuel Cell Catalyst Layer Fabrication

“…The inclusion of new materials in catalytic ink formulations is also being explored by some research groups. Electrospray deposition of some innovative catalyst support materials has been reported, such as graphene, carbon nanotubes, Ta-doped SnO 2 , and Ni-doped TiO 2 nanofibers . The publication of the first investigation dealing with the fabrication of platinum group metal-free catalyst layers with the objective of reducing the inherent mass-transport limitations of this type of catalyst is also remarkable .…”

An interconnected-graphene enveloped titanium dioxide flower as a robust support for proton exchange membrane fuel cells

“…Among various strategies, constructing TiO 2 and carbon composites has emerged as the most effective way. The synthetic routes to composite materials can be classified into three categories: (1) a physical mixture of TiO 2 nanoparticles and carbon materials; [19][20][21][22] (2) in situ growth of TiO 2 on a carbon substrate; [23][24][25][26] and (3) composites made from pyrolysis of carbon sources and TiO 2 . [27][28][29][30] These composites have improved the electrical conductivity of TiO 2 and the electrochemical stability of carbon, demonstrating promise for application in PEMFCs.…”