Superior durability and stability of Pt electrocatalyst on N-doped graphene-TiO2 hybrid material for oxygen reduction reaction and polymer electrolyte membrane fuel cells

摘要

To accelerate the commercialization of polymer electrolyte membrane fuel cells (PEMFCs), studies on durable support materials that can replace conventional carbon-based supports are being conducted. In this study, we prepared N-doped TiO2 on the N-doped graphene hybrid material (NG-TiON) using a facile hydrothermal method to develop a support for a platinum catalyst with both high stability and electrical conductivity. Asprepared NG-TiON supports were characterized using transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The stability of the Pt/NG-TiON catalyst was considerably improved compared to that of Pt/C, and their high oxygen reduction reaction (ORR) activities were similar. The durabilities of the Pt catalysts were investigated using the accelerated durability test. Single cell measurements revealed that Pt/NG-TiON has high stability and corrosion resistance with a performance degradation rate of only 9 % after 5000 accelerated durability test cycles while the performance of Pt/C decreased 83 %.