Nanotechnology in Fuel Cells
July 28th, 2012 nanoguru
Fuel cells are the next generation power source of electric vehicles. Typically, fuel cell is a device which converts a fuel directly into electricity in an electrochemical reaction. The fuel cells are electrochemical devices that combines hydrogen and oxygen to produce electricity, with water and heat as its by-product. A fuel cell consists of two electrodes, an anode and a cathode, with an electrolyte between them. The research in the field of fuel cells have thrown light in to the new ways to revolutionize transportation using fuel cells. The electric motors in this fuel cell vehicles will be powered by highly efficient fuel cells.
As the fuel cells are the next generation power sources, the research in this field is also getting much attention. The problem with the existing fuel cells are it contain membranes that allow hydrogen ions to pass through the cell but do not allow other atoms or ions. So, for this purpose membranes with better characteristics to be needed. Now researchers are using nanotechnology to create more efficient membranes; the new membrane will allow them to build longer lasting and lighter weight fuel cells.
The common catalysts used in fuels are hydrogen or methanol, to produce hydrogen ions. Platinum, a most expensive material is used as a catalyst in this process. As the platinum is an expensive material, a more economical material is needed to reduce the cost of fuel cells. The Research will lead to the replacement of nanoparticles of platinum as a catalyst to reduce the amount of platinum needed. The experiment is underway to use nanoparticles of other materials to replace platinum entirely and thereby lowering the cost of production. The catalytic electrodes in fuel cells has been replaced with platinum nanoparticles instead of a solid platinum surface. This will increases the efficiency, and allows much less platinum metal to be used.
For the case of transportation applications, the proton exchange membrane (PEM) fuel cells (also known as polymer electrolyte membrane fuel cells) are using. These fuel cells are powered by the electrochemical oxidation reaction of hydrogen and by the electro reduction of the oxygen contained in air.
Nanotechnology offers cheap bipolar materials using Nano composites, more efficient and less cost, non-platinum electro catalysts. The more thermally stable and more durable membranes to become available in the near future.
Another important invention this field is the use of carbon nanotubes. Modified carbon nanotubes can be used to replace platinum in fuel cells. By doping carbon nanotubes with nitrogen, or coating them in an electron-withdrawing polymer (polydiallyldimethylammonium chloride, or PDDA), the electronic properties of the nanotubes can be altered so as to make them effective as a catalyst and the electro catalytic activity of these modified nanotubes is found to be superior to that of platinum.
Now the problems with the fuels using in the fuel cell. At this time, commercial fuel cells can only run on a limited range of fuels. Most of the fuel cells using hydrogen, and some fuel cells are able to use methanol or natural gas. Further researcher in this field brings the fuel cells, highly efficient, portable and powerful power source. You can find different companies working in the field of fuel cells from understanding nano and comparison of fuel cells type is available in Wikipedia.
What you think about the future of fuel cells? Can it satisfy our need for highly efficient, portable power source for electric vehicles?