Alternative architectures and materials for PEMFC gas diffusion layers: a review and outlook

This paper reviews some of these new innovations in both the macroporous substrate and the microporous layer (MPL). A diverse range of macroporous substrates and designs is shown, encompassing various carbon-based and metal-based materials and innovative fabrication methodologies. A critical assessment of innovative MPL materials and designs for performance improvements is presented, taking into account pore size distribution and microstructure. An analysis of the effect of wettability and hydrophobic agents in the substrate and MPL is performed. One of the notable findings is that, among other key findings, significant performance enhancement is realised through employing graduated porosity and/or wettability GDLs. Finally, recommendations for future work into GDL materials and designs are made, with the aim of ultimately improving the overall cell efficiency.