“…9 However, carbon black suffers from being vulnerable to carbon corrosion, especially in harsh operating environment of PEM fuel cells, which might lead to the detachment and aggregation of catalyst metal particles. 5,6,8 Rather than carbon black, other carbonaceous materials have been investigated, so far, for this purpose, such as ordered mesoporous carbons, 4,10,11 carbon xerogel, 12 carbon nanotubes, 13 carbon nanofibers, 14 porous carbon nanofiber, 5 and graphene-based materials, 1, 15,16 to find the one with optimized form and structure for better efficiency and/or durability. It resulted that the support structure has a strong effect on the number and mechanism of electron transportation in ORR.…”