Electrocatalytic properties improvement on carbon-nanotubes coated reaction surface for micro-DMFC

In this paper, the enhancement of electrocatalytic performance of carbon nanotubes (CNTs) grown on silicon substrate was demonstrated as compared with the conventional reaction surfaces including bare silicon wafer, carbon cloth and carbon paper, and all were with a thin Pt film (10 nm) coating. The peak current density was doubled by the Pt film/CNTs electrode comparing to Pt film/carbon cloth and about six times comparing to silicon wafer because of the large reaction surface area and excellent CO2 microbubble removal capability by the CNTs nanostructure. The results indicated that the electrocatalytic performance of catalyst was significantly improved for the peak current density on better linear relationship to methanol concentration and square root of sweeping-rate, better exponential relationship to temperature and higher peak current density on different substrate tiling angles, which greatly attribute to the rapid microbubbles removal on nanostructured hydrophilic CNTs surface. These conclusions can be taken as references to designing micro-DMFC in the future.