The effect of the Pt deposition method and the support on Pt dispersion on carbon nanotubes

Carbon nanotube supported platinum (Pt/CNTs) catalysts prepared by different Pt deposition methods and on different CNT supports were studied. Colloidal based methods were demonstrated to be more effective than other wet chemistry deposition methods (e.g., impregnation and precipitation) for the preparation of highly dispersed Pt/CNTs. Pt catalyst supported on CNTs with a dispersion uniformity comparable to that supported on carbon powder was achieved using a zwitterionic surfactant 3-(N,N-dimethyldodecylammonio) propanesulfonate (SB12) as stabilizer in a monitored pH environment. It was experimentally observed that oxygen-containing surface functionalities on CNTs can greatly affect the catalyst particle dispersion by manipulating Pt anchoring and/or nucleating sites. Furthermore, it was revealed that the performance of Pt/CNTs based fuel cell is strongly dependent on the electrode fabrication method.