Carbon Nanotube Thin Films and Hybrid Structures for Supercapacitor and Fuel Cell Applications

The development of low cost and environmentally friendly energy conversion and storage systems is currently of the utmost priority. Here we discuss the impact of chemical design of carbon nanomaterials on their performance as active materials for supercapacitor and catalyst support for fuel cell applications.

Chemical modification of single-walled carbon nanotubes (SWNTs) and graphene, is a powerful means to improve the charge capacitance of the materials. By introducing oxygen-containing groups the gravimetric capacity of SWNTs and graphene can be doubled. Furthermore, the combination of 1D SWNTs and 2D graphene affords hybrid structures with enhanced synergistic electrochemical performance.

We also demonstrate the advantages of functionalized SWNTs for the fabrication of SWNT thin film catalyst support layers in polymer electrolyte membrane fuel cells (PEMFCs). Introducing an optimum level of carboxylic groups in the SWNTs allows the fabrication of SWNT-based PEMFC with efficient Pt catalyst utilization. This offers an attractive route to the manufacture of highly efficient fuel cells that meet some of the US DOE 2017 technical targets.