The effect of titania nano-particles doping on the performance of platinum-graphene oxide catalyst for proton exchange membrane fuel cells

Abstract

An effective strategy to design highly active nanocatalysts is to use hybrid nanocatalysts including Graphene Oxide-Titania-Platinum (GO-TiO2-Pt). This study attempts to synthesize these highly efficient nanocatalysts. GO-TiO2 nanocatalysts are synthesized hydrothermal hydrolysis of TiOSO4 in an acidic suspension of GO. Platinum nanoparticles were deposited on GO-TiO2 by borohydride reduction of H2PtCl6. Nanocatalysts were prepared with varied weight contents of Pt (2–20 wt%), afterward GO-TiO2-Pt-Nafion composites were obtained. The nanocatalysts were characterized by FTIR, XRD, UV–Vis, SEM, EDX and dot mapping analysis. Furthermore, catalytic activity toward methanol oxidation reaction of GO-TiO2-Pt-Nafion composites was evaluated via cyclic voltametery (CV) measurements. XRD analysis revealed that the unreduced TiO2 is in the form of anatase. The average diameters of the TiO2 and Pt nanoparticles were 20 and 16 nm, respectively. Results show that, doping of 10% (wt/wt) or higher amount of the Pt nanoparticles on the graphene nanosheets caused to occurring the methanol oxidation reaction.