Pt/C catalysts using different carbon supports for the cathode of PEM fuel cells
20 wt% Pt/C catalysts were prepared using a chemical reduction method, with pristine double-walled carbon nanotubes (DWCNTs) and activated double-walled carbon nanotubes, respectively, used as the carbon source, and compared to commercial BASF 20 wt% Pt/C (using Vulcan XC-72 carbon as support). The materials were characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy and Brunauer- Emmett-Teller (BET) surface area measurements. The electrochemical performance of the Pt/C catalysts was evaluated by cyclic voltammetry, steady-state measurements, and chronoamperometric testing. Electrochemical measurements indicate that the Pt nanocatalysts exhibited enhanced electrochemically active surface areas and improved activity in the oxygen reduction reaction (ORR) on the chemically activated double-walled carbon nanotubes compared to the pristine double-walled carbon nanotubes or the Vulcan XC-72 carbon. It is suggested that activated double-walled carbon nanotubes would provide better catalyst support than Vulcan XC-72 carbon.