Dual-bonded catalyst layer structure cathode for PEMFC

Novel electrode structure based on dual-bonded catalyst layer structure is reported to elevate proton exchange membrane fuel cell (PEMFC) cathode performance. Differing from conventional cathode with simplex PTFE or ionomer as binder material in catalyst layer (CL), dual-bonded CL combines those two types of binders, respectively, in a composite structure. In order to develop a cathode possessing the superior merits of both mass transport and proton transfer, a PTFE-rich CL and an ionomer-rich CL were fabricated on gas diffusion layer in proper order. Polarization characteristic of cathodes with dual-bonded CL, conventional PTFE-bonded CL and ionomer-bonded CL were evaluated at ambient pressure in oxygen/air. Better performance of cathode was achieved with dual-bonded, compared with conventional structures. Electric yield rate of dual-bonded cathode was about 50%, whilst that of conventional cathodes was about 40%.