A novel CNT@SnO2 core-sheath nanocomposite as a stabilizing support for catalysts of proton exchange membrane fuel cells

Mesoporous SnO2 coated carbon nanotube (CNT) core-sheath nanocomposite, CNT@SnO2, was prepared by a hydrothermal method and proposed as a catalyst support for proton exchange membrane fuel cells (PEMFCs). The CNT@SnO2 and its supported Pt catalyst, Pt/(CNT@SnO2), were characterized by TEM, XRD, cyclic voltammetry, and polarization curves. The CNT@SnO2 composite showed a much lower anodic current than the CNT, especially at high potentials, indicating the CNT@SnO2 was more corrosion resistant. The Pt/(CNT@SnO2) catalyst was electrochemically active and exhibited comparable activity for the oxygen reduction reaction to the CNT supported catalyst (Pt/CNT). More importantly, the long-term stability of the Pt/(CNT@SnO2) catalyst was significantly higher than that of the Pt/CNT catalyst, which might be mainly due to the fact that the CNT@SnO2 was more corrosion resistant and mesoporous SnO2 was beneficial to restrict the Pt migration and aggregation. Consequently, the CNT@SnO2 would be a promising durable catalyst support for PEMFCs. (C) 2008 Elsevier B.V. All rights reserved