Gas diffusion layer with PTFE gradients for effective water management in PEM fuel cells

Abstract

Experimental procedures to establish in-plane and through plane polytetrafluroethylene (PTFE) gradient in Gas Diffusion Layer (GDL) used in proton exchange membrane fuel cells (PEMFC) are presented in this work. In-plane PTFE gradients were obtained by exploiting capillary wicking of PTFE suspension. The through plane PTFE gradients were obtained by changing the drying temperature employed in PTFE loading procedure. The samples were characterized for fluorine distribution using energy dispersive spectrum (EDS) to gauge the PTFE distribution and change in hydrophobicity after PTFE treatment. The results indicate that manipulation of PTFE gradients are expected to result in effective water management in PEMFC.