“…Numerous catalyst support materials for PEMFCs have been actively investigated, like various high surface area carbon [5], boron-doped carbon [6], carbon nanofibers (CNFs) [7], multi-walled carbon nanotubes (MWCNTs) [8,9], CNTs directly grown carbon paper [10,11], single-walled carbon nanotubes (SWCNTs) [12], etc. However, MWCNTs and their composites as catalyst support material have wide-scale interest due to their unique properties such as high chemical and oxidative stability, extraordinary mechanical strength, good electronic conductivity, high surface area and relatively simple manufacturing process.…”