Appropedia needs your support - Please Donate Today

Carbon nanotubes and the hydrogen fuel cell

From Appropedia
Jump to: navigation, search

Carbon nanotubes in the hydrogen fuel cell[edit]

Many envision that vehicles of the future will be powered by renewable hydrogen, whose exhaust is pure water rather than the dangerous CO2 emissions. The hydrogen fuel cell is making that vision happen. The fuel cell must be able to handle the explosive properties of hydrogen while making a good source of renewable energy for the user. There are many advances in nanotechnology that are improving the efficiency of the hydrogen fuel cell, making it more affordable and accessible to people in developing nations. This article will focus on the use of carbon nanotubes in proton exchange fuel cells, and give insight into how carbon nanotubes are used to make fuel cells safer, more affordable, and more accessible to the developing world.

Improving the hydrogen fuel cell with carbon nanotubes[edit]

Hydrogen fuel cells basically “converts the chemicals hydrogen and oxygen into water, and in the process it produces electricity” [1]. A good picture of the fuel cell is available from [1].

Safer fuel cells are being developed using single-walled carbon nanotubes (SWCN) to build more efficient hydrogen sensors. Growing carbon nanotubes improves efficiency improves the utilization of the catalyst, and is therefore an improvement over carbon powders [2]

The multi-walled carbon nanotubes (MWNTs) make good electrical contact to the substrate (carbon paper). Although at the time of this research, Platinum particles were rather large, the researchers believed that decreased size in future would also increase the efficiency of the fuel cell . The “Single-Wall Carbon Nanotube-Based Proton Exchange Membrane Assembly for Hydrogen Fuel Cells” uses a platinum catalyst and is about 20% more efficient than the CFE/CB/Pt electrodes. This process improved the “performance of h2-based PEM fuel cells especially at higher pressures”. [3] Research done with nano-sturctured hydrocarbon membranes in 2004 also helped to make the fuel cell more economical. The membrane, says Jim Balcom of PolyFuel Inc, “uses a lattice of nano-structured hydrocarbons to support a grid of conductive blocks through which protons flow as the cell generates electricity”. [4]

Fuel Cell System Components[edit]

  • separator plates, current collector plates, membrane electrode assembly (MEA), gaskets, and possibly heaters.
  • All the fuel cell requires to generate electricity is hydrogen and oxygen gas, or air.
  • Semi-permeable membrane must allow H through while blocking other elements


Carbon nanotube based fuel cell components[edit]

  • platinum or other precious metal catalyst
  • carbon paper for growing nanotubes


References[edit]

  1. How Stuff Works, it’s good to know. How Fuel Cells Work by Karim Nice and Jonathan Strickland. Accessed 1/26/08. Available: http://auto.howstuffworks.com/fuel-cell.htm
  2. Article: Proton Exchange Membrane Fuel Cells with Carbon Nanotube Based Electrodes. Nano Letters. 2004, Vol. 4, No. 2, 345-348. Cheng Wang et. al. American Chemical Society, 2004.
  3. Single-Wall Carbon Nanotube-Based Proton Exchange Membrane Assembly for Hydrogen Fuel Cells. G. Girishkumar et. al. Langmuir 2005, 21, 8487-8949. American Chemical Society
  4. Article: Proton Exchange Membrane Fuel Cells with Carbon Nanotube Based Electrodes. Nano Letters. 2004, Vol. 4, No. 2, 345-348. Cheng Wang et. al. American Chemical Society, 2004.

Article: New membrane makes cheaper, stronger fuel cells. David Forman. SmallTimes. 17 Dec. 2004. Available: http://www.smalltimes.com/article/article_display.cfm?ARTICLE_ID=269761&p=109