Catalyst support materials exhibit great influence on the performance and durability of proton exchange membrane (PEM) fuel cells. This minireview article summarises recent developments into carbon nanotube-based support materials for PEM fuel cells, including the membrane electrode assembly (MEA). The advantages of using CNTs to promote catalyst performance and stability, a perspective on research directions and strategies to improve fuel cell performance and durability are discussed. It is hoped that this minireview will act as a conduit for future developments in catalyst supports and MEA design for PEM fuel cells.

Hierarchically structured carbon coated SnO₂ nanoparticles well-anchored on the surface of a CNT (C–SnO₂/CNT) material were synthesized by a facile hydrothermal process and subsequent carbonization. The as-obtained C–SnO₂/CNT hybrid, when applied as an anode material for lithium ion batteries (LIBs), showed a high reversible capacity up to 1572 mA h g⁻¹ at 200 mA g⁻¹ with a superior rate capability (685 mA h g⁻¹ at 4000 mA g⁻¹). Even after 100 charge/discharge cycles at 1000 mA g⁻¹, a specific capacity of 1100 mA h g⁻¹ can still be maintained. Such impressive electrochemical performance can be mainly attributed to the hierarchical sandwiched structure and strong synergistic effects of the ultrafine SnO₂ nanoparticles and the carbon coating, and thus presents this material a promising anode material for LIBs.

Microwave-assisted heating of functionalized, single-wall carbon nanotubes (FCNTs) in ethylene glycol solution containing H₂PtCl₆, led to the reductive deposition of Pt nanoparticles (2.5–4 nm) over the FCNTs, yielding an active catalyst for proton-exchange membrane fuel cells (PEMFCs). In single-cell testing, the Pt/FCNT composites displayed a catalytic performance that was superior to Pt nanoparticles supported by raw (unfunctionalized) CNTs (RCNTs) or by carbon black (C), prepared under identical conditions. The supporting single-wall carbon nanotubes (SWNTs), functionalized with carboxyl groups, were studied by thermogravimetric analysis (TGA), cyclic voltammetry (CV), and Raman spectroscopy. The loading level, morphology, and crystallinity of the Pt/SWNT catalysts were determined using TGA, SEM, and XRD. The electrochemically active catalytic surface area of the Pt/FCNT catalysts was 72.9 m²/g-Pt.