Gao Jie, Zhongyin Sun, Jie Wang, Chaohua Fan, Xuejing Cui, Jing Liu*, Luhua Jiang*

Electrocatalysis & Nanomaterial Laboratory, College of Materials Science & Engineering,

Qingdao University of Science & Technology, Qingdao, 266042, P.R. China

Abstract:

Support corrosion is a traditional intractable problem for oxygen electrodes of both fuel cells and water electrolysis, so developing anti-corrosion supports is highly desirable. Herein, we fabricate a three-dimensional (3D) interconnected-graphene enveloped titanium oxide flower (TiO₂@RGO) as a robust support for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Benefiting from the unique 3D architecture, the TiO₂@RGO composite possesses both high surface area of 174 m²·g^-1 and superior electrical conductivity of 0.19 S cm^-1, enabling an electron highway simultaneously efficient mass transfer for reactants. After loading Pt nanoparticles, the Pt-TiO₂@RGO catalyst exhibits similar catalytic activity as 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 the 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 poses a new strategy for designing robust catalyst supports for PEMFCs.

DOI: 10.1039/d2dt01219g