Abstract
Proton exchange membrane fuel cells (PEMFCs) have generated considerable interest as a power source for portable electronics and automobiles because of their high power density at lower temperatures, environmentally friendly nature and compact design. The catalyst layers are the one of important factors in determining the efficiency of PEMFCs. In order to increase the efficiency of PEMFCs, the catalysts with smaller particle size and highly dispersion were readily characterized. In order to enhance catalytic properties, carbon nanotubes (CNTs) as catalyst supports have sparked an interest due to their high surface area, strong mechanical properties and good electronic conductivity. However, obtaining highly dispersed Pt nanoparticles is still a challenge. Thus, this study investigated high loading Pt nanoparticles on multiwalled carbon nanotubes by electrodeposition method applied for the anode of PEMFCs. In the experiment, CNTs were directly grown on the gas diffusion layer by chemical vapor deposition (CVD) and then treated with hydrophilic process. After that, Pt nanoparticles were deposited on CNTs by the electrochemical method in chloroplatinic acid and citric acid at 30℃. The electrochemical characterizations of catalysts were obtained by cyclic voltammetry in argon saturated 0.5M H2SO4 and 0.5M H2SO4 with 1M CH3OH solution, respectively. Pt/CNTs/Carbon Cloth or Carbon Paper were characterized by SEM, TEM, XPRD, HRXPS and ICP-MS. Finally, The single cell tests indicated the power density of the homemade MEA could reach up to 927 mW/cm2 which is 50% higher than that of the commercial MEA.