Plasma Sputtering Deposition of PEMFC Porous Carbon Platinum Electrodes

Abstract

A novel method is proposed to fabricate the active catalytic layers of proton exchange membrane fuel cells (PEMFC). A plasma sputtering technique is used to deposit a porous columnar carbon film (column diameter of 20 nm) followed by the catalyst (platinum) deposition directly on the proton‐conducting membrane. The study of Pt diffusion shows that the optimised catalysed layers correspond to low plasma pressure operation (0.5 Pa) below a platinum loading limit of about 90 μg cm–2. The initial carbon porosity is then maintained and Pt nanoparticles are present in all parts of the carbon layer. A membrane electrode assembly (MEA) is then achieved by alternate depositions of carbon and platinum onto both sides of the membrane. The results show the importance of the porous carbon structure. A significant increase in the catalyst efficiency is observed compared to a commercial fuel cell when measuring open circuit voltage.

Molecular Dynamics Simulations of Platinum Plasma Sputtering: A Comparative Case Study

“…Due to its high cost, it has been necessary to find deposition techniques suitable for lowering its quantity and at the same time retaining or increasing its catalyst activity and its selectivity. Among the various existing possibilities, plasma sputtering deposition has attracted attention due to its simplicity, scalability in the industry [2][3][4] and in the case of noble metal catalyst, its capability for controlling catalyst shape, size, and concentration profile in catalytic active layers [5][6][7][8][9][10][11]. This capability is largely dependent of the sputtering conditions as bias potential of the sputtering target or as the nature of the plasma forming elements.…”

Do not forget the electrochemical characteristics of the membrane electrode assembly when designing a Proton Exchange Membrane Fuel Cell stack

“…Such a structure is meaningful for PEMFC electrodes. Indeed, codeposition or alternate deposition of carbon and platinum can lead to multilayer C-Pt catalysts or carbon columns decorated by a gradient of Pt nanoclusters [77,78]. Moreover, the 18 structures of Gas Diffusion Electrodes (GDE) prepared either by alternate deposition or by codeposition (from a target composed of 1 wt% Pt and 99 wt% C) of platinum atoms and carbon atoms on the GDL are completely different, as SEM images of the cross section of the GDEs, given in Figures 18b and c, show clearly that the density of platinum is higher on the top of the GDE in the case of the alternate deposition, whereas its repartition seems more homogeneous in the case of co-sputtering.…”

Cold Plasma – A Promising Tool for the Development of Electrochemical Cells

“…Carbon and platinum can be also deposited by subsequent sputtering processes. First a porous columnar carbon film (column diameter of 20 nm) is deposited, and then these nanocolumns are decorated by Pt nanoclusters (Rabat & Brault, 2008).…”