High-performance nanostructured membrane electrode assemblies for fuel cells made by layer-by-layer assembly of carbon nanocolloids

Utilization of carbon nanotube and nanofiber composites made by layer-by-layer (LBL) following a technology used previously for making ultrastrong materials for proton exchange membrane (PEM) fuel cells is discussed. LBL has been used successfully to prepare substructures for PEM fuel cells as a tool for balancing different conflicting requirements. The triple phase boundary (TPB) regions for the catalyst layer must have a balance between the ionic and electronic conducting mediums that influences the hydrophilic and hydrophobic properties of the nanocomposites. Three essential properties required by a fuel cell electrode includes electrical conductivity, proton conductivity, and efficiency of the catalytic reaction of the platinum (Pt) particles. The promising values of peak power density and Pt utilization are attributed to the balancing of the diverse requirements of the membrane electrode assembly (MEA) and are obtained because of the intrinsically favorable properties of LBL films.