Abstract
Polymer electrolyte based fuel cells (PEFCs) are always in the forefront of fuel cell revolution. Recently a wide variety of application of carbon nanotubes (CNTs) in PEFC components has been exploited. The impetus is to improve the PEFC performance by taking advantages of CNTs' extraordinary physical, chemical and electronic properties. Herein, we briefly review these efforts with an attempt to obtain a better understanding on the role of CNTs in PEFCs, and this article is structured as the following: the contribution of CNTs is first addressed in terms of improving the mechanical strength and proton conductivity of polymer electrolyte membrane; their role in electrocatalysis is then discussed with respect to facilitating the utilization of noble metal catalysts (platinum) and exploring the platinum-free catalysts; the consideration of CNTs as hydrogen storage materials is also highlighted. Based on the literatures studied, CNTs demonstrate great potential as multifunctional materials in improving PEFC performance.