The current collector defines how electrons enter and leave a membrane-electrode assembly, and at electrolyzer or fuel-cell potentials it sits in the harshest environment in the stack — wet, hot, and either strongly oxidizing or aggressively reducing. This collection groups the substrates we stock specifically for PEM, AEM, alkaline, and high-temperature electrolysis and fuel-cell research: porous gas-diffusion media, corrosion-resistant metal foils, woven meshes, sintered felts, and open-cell metal foams.
Gas-diffusion layers
For PEM fuel cells and PEM water electrolyzers, hydrophobic carbon papers with an integrated microporous layer (MPL) and PTFE coating bridge the bipolar plate and the catalyst layer. The MPL/PTFE structure manages liquid-water removal so the cathode does not flood at high current density, while the through-plane carbon backbone keeps contact resistance low. We carry GDL carbon papers in several thicknesses for both cathode and anode side studies.
Corrosion-resistant metal substrates
Above the carbon stability window — PEM electrolyzer anodes, accelerated stress tests, or any acidic environment beyond ~1.6 V vs RHE — carbon papers degrade and metal collectors take over. Tantalum foil offers exceptional stability in hot acidic media; titanium foam and titanium-based porous transport layers are the workhorses for OER-side PEM water electrolysis; nickel felt is the standard alkaline-side current collector for alkaline electrolyzers and AEM cells; and silver mesh is used for SOFC cathode-side collection in the intermediate-temperature window where it stays conductive in oxygen-rich atmospheres.
3D porous architectures
Foams, felts, and woven meshes provide a flow-through path so reactant gas or electrolyte reaches the catalyst layer while electrons travel along a continuous metallic network. Compared to flat foils, the 3D structure raises catalyst utilization, improves bubble release at high current density, and gives a mechanically compliant interface against the membrane.
Choosing a substrate
- PEM fuel cell or PEM electrolyzer cathode — start with hydrophobic carbon paper with MPL/PTFE.
- PEM electrolyzer anode (OER side) — use titanium foam or titanium PTL; tantalum foil for the most aggressive acidic conditions.
- Alkaline or AEM electrolyzer — use nickel felt or nickel foam.
- SOFC / SOEC intermediate-temperature cathode — use silver mesh.
For the membranes and ionomers that pair with these collectors, see Electrolyzers & Fuel Cells; for battery-side current collectors (Cu, Al, carbon-coated foils), see the battery current-collector collections.
