To improve the electrocatalytic properties of PtRu/C in methanol electrooxidation, nanoparticulate TiO 2 -promoted PtRu/C catalysts were prepared by directly mixing TiO 2 nanoparticles with PtRu/C. Using cyclic voltammetry, it was found that the addition of 10 wt% TiO 2 nanoparticles can effectively improve the electrocatalytic activity and stability of the catalyst during methanol electro-oxidation. The value of the apparent activation energy (E a ) for TiO 2 -PtRu/C was lower than that for pure PtRu/C at a potential range from 0.45 to 0.60 V. A synergistic effect between PtRu and TiO 2 nanoparticles is likely to facilitate the removal of CO-like intermediates from the surface of PtRu catalyst and reduce the poisoning of the PtRu catalysts during methanol electrooxidation. Therefore, we conclude that the direct introduction of TiO 2 nanoparticles into PtRu/ C catalysts offers an improved facile method to enhance the electrocatalytic performance of PtRu/C catalyst in methanol electrooxidation.
IntroductionCarbon-supported PtRu catalyst, PtRu/C, offers a state-of-the-art anode electrocatalyst for direct methanol fuel cells (DMFCs) due to its high activity toward methanol electrooxidation and tolerance to carbon monoxide poisoning [1][2][3][4][5]. Alloying Pt with Ru promotes the formation of oxygenated species at a lower temperature than Pt particles and promotes oxidation of CO to CO 2 . However, despite promising progress in the development of PtRu/C, the durability and activity of the PtRu/C anode still cannot meet the demands for practical DMFCs applications.