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

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

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

Abstract:

Carbon materials are extensively employed as supports for electrocatalysts in fuel cells, however, carbon corrosion in strong acidic and oxidizing conditions is a serious issue, thus developing a robust catalyst support is essential to ensure the stability of fuel cells. Herein, we report a unique support of few-layered nitrogen-doped graphene wrapped three-dimensional (3D) flower-like anatase TiO₂ (TiO₂@N-Gr) via in-situ polymerizing dopamine on surface of a 3D-TiO₂ flower precursor, followed by a pyrolysis process. After loading Pt nanoparticles, Pt-TiO₂@N-Gr-800 exhibits a comparable ORR activity to the commercial Pt/C catalyst (E_1/2 = 0.91 V_RHE), while superior stability in a 30K cycling stability test and strong capability of CO resistance. The outstanding performance of the Pt-TiO₂@N-Gr-800 catalyst is attributed to the strong anti-corrosion property and high electronic conductivity of the nanocomposite support, as well as a strong metal and support interaction. The unique flower-like scaffold is also of great advantage for mass transfer. This work provides a facile strategy to synthesize robust nanocomposite supports for fuel cells.

Keywords: Nanocomposite support; oxygen reduction reaction; titanium oxide; electrocatalyst; stability