An interconnected-graphene enveloped titanium dioxide flower as a robust support for proton exchange membrane fuel cells.

Support corrosion is a traditional intractable problem for oxygen electrodes of fuel cells, so developing anti-corrosion supports is highly desirable. Herein, we fabricate a three-dimensional (3D) interconnected-graphene enveloped titanium dioxide flower (TiO 2 @RGO) as a robust support for the oxygen reduction reaction (ORR). Benefiting from the unique 3D architecture, the TiO 2 @RGO composite possesses both a large surface area of 174 m 2 g -1 and a superior electrical conductivity of 0.19 S cm -1 , enabling an electron highway for efficient simultaneous mass transfer of reactants. After loading Pt nanoparticles, the Pt-TiO 2 @RGO catalyst exhibits a similar catalytic activity to the commercial Pt/C catalyst, while superior stability under the accelerated degradation protocols for both catalysts (0.6-1.0 V RHE ) and supports (1.0-1.5 V RHE ), due to the strong metal-support interaction (SMSI) of Pt nanoparticles and the TiO 2 @RGO composite support. The PEMFC with the Pt-TiO 2 @RGO cathode delivers a peak power density of 901 mW cm -2 , which is comparable to that with a Pt/C cathode. This work proposes a new strategy for designing robust catalyst supports for PEMFCs.