Paper NS-TuP15
Refreshable Pt-TiO₂ Nano-Composite for Direct Methanol Oxidation

Tuesday, October 29, 2013, 6:00 pm, Room Hall B

Direct Methanol Fuel Cell (DMFC) has been deemed as one of the many feasible candidates for the portable power supply of the next generation. However, the slow process of methanol oxidation has been the root problem in the development of DMFC. Platinum based alloys have been widely developed and commonly utilized as the catalyst in methanol oxidation. In another field of technology, metal-titanium oxide composite has been adopted in distillation for decades due to the improved photo- catalytic capability resulting from the prolongation of recombination time between electrons and holes thereof. In this paper, Pt- TiO₂ composite nanostructure was deposited on carbon cloth by a one- step photo-deposition process in the atmospheric condition. Various surface compositions of Pt-TiO₂ nano composites were prepared. Also, a comparative study was conducted aiming at assessing the enhancement on the oxidation current of methanol, the suppression of CO poison, and the durability in acidic surrounding among the aforesaid Pt-TiO₂ nano composites. Furthermore, the electrochemical characteristics of photo enhanced methanol oxidation were studied via cyclic voltammetry and chronoamperometry under various illumination conditions. More than 40% of enhancement on the oxidation current density was found on the Pt-TiO₂ modified carbon cloth under UV illumination. The photo induced hydrophilicity also contributed to the local mass transfer on the surface of the aforesaid composite catalyst during the durability test. Moreover, the durability test also suggests the dispersion of TiO₂ NPs and the adhesion between TiO₂ NPs and carbon fibers play crucial roles in the performance of DMFC. In summary, the preliminary results suggest, with proper design on the surface composition, the Pt-TiO₂ nano-composite exists a great potential to serve as the anodic catalyst in DMFC.