An interconnected-graphene enveloped titanium dioxide flower as a robust support for proton exchange membrane fuel cells†
Abstract
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 (TiO2@RGO) as a robust support for the oxygen reduction reaction (ORR). Benefiting from the unique 3D architecture, the TiO2@RGO composite possesses both a large surface area of 174 m2 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–TiO2@RGO catalyst exhibits a similar catalytic activity to the commercial Pt/C catalyst, while superior stability under the accelerated degradation protocols for both catalysts (0.6–1.0VRHE) and supports (1.0–1.5VRHE), due to the strong metal–support interaction (SMSI) of Pt nanoparticles and the TiO2@RGO composite support. The PEMFC with the Pt–TiO2@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.