Hydrophilic catalyst layer preparation process

Membrane-based Hydrophilic Catalyst Layer. Wilson and Gottesfeld [8, 21-23] suggested an ionomer-bonded hydrophilic catalyst layer prepared with the decal transfer method. The so-called decal transfer process includes two key steps (1) coating catalyst ink onto a blank substrate (e.g., PTFE film) then (2) transferring the coat onto the membrane (as shown in Figure 19.6). A typical preparation procedure is as follows ... 

Regarding the inherent problems with proton/gas transport for the hydrophobic or hydrophilic types of catalyst layers, a dual-bonded composite CL was suggested first by Zhang et al. [50, 51] in order to alleviate the drawbacks and promote the merits of the individual CL. Zhang and Shi [52, 53] also investigated such dual-bonded composite CLs by optimizing various components used. This dual-bonded CL cathode has two layers. The first is the hydrophobic layer with PTFE as a binder material, which is fabricated directly on the surface of the GDL. The second is a hydrophilic layer with Nafion as a binder material, which is fabricated on top of the hydrophobic layer surface. The typical preparation process can be summarized as follows ... 

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