A novel hydrophilic‐modified gas diffusion layer for proton exchange membrane fuel cells operating in low humidification

A novel hydrophilic-modified gas diffusion layer (GDL) through inserting the polyacrylonitrile (PAN) into the microporous layer is fabricated to elevate the performance of the proton exchange membrane fuel cells (PEMFCs) under low humidfication. The single fuel cell test confirms that the membrane electrode assembly with 3 wt% addition of PAN in the cathode GDL exhibits a maximum power density of 0.616 W cm−2, which is 30% higher than that of conventional hydrophobic GDL (0.480 W cm−2) under low humidity. This significant enhancement in performance is attributed to the powerful wettability and the pore structure modification of the PAN. Besides, the introduction of PAN shows little influence on the performance of PEMFCs under full humidity. Our findings reported here shed new light on developing a robust GDL that can be used in both low and high humidification.