Fuel cells
Fuel cells are the most important electrochemical tools for the direct conversion of chemical energy to electrical energy and they are secure and environment-friendly. The electrodes are very important pieces of the cells which is usually produced using costly platinum metal as anode in the electro-oxidation of methanol in fuel cells. Iranian researchers at University of Mazandaran produced an electrode with the help of carbon nanotubes, which can increase the rate of electro-oxidation of methanol in fuel cells.
Methanol fuel cell
DMFC has a polymer electrolyte and the charge carrier is the hydrogen ion (proton). The liquid methanol (CH3OH) is oxidized in the presence of water at the anode generating CO2, hydrogen ions and the electrons that travel through the external circuit as the electric output of the fuel cell.
One of the drawbacks of the DMFC is that the low-temperature oxidation of methanol to hydrogen ions and carbon dioxide requires a more active catalyst, which typically means a larger quantity of expensive platinum catalyst is required which increases cost but of course without a reforming unit.
Carbon nanotubes
Carbon nanotubes are molecular-scale tubes of graphitic carbon with outstanding properties having stiffest and strongest fibers known with remarkable electronic properties and many other unique characteristics. For these reasons they have attracted academic, industrial and commercial applications. According to the scientists, using nanotubes modified electrodes has been developed due to the unique structural ability and amazing physico-chemical properties such as high ratio of area to volume and high electrical conductivity. The production of from the carbon paste containing modified carbon nanotubes was achieved.
Production
The electrode was produced by synthesizing the carbon paste containing carbon nanotube by mixing graphite powder, paraffin oil and multi-walled carbon nanotube. Then, it is modified with poly (meta-toluidine)/triton through a voltammetric cycling method. Finally, the platinum particles are electrochemically precipitated on the polymeric film existing on the surface of the electrode in order to produce the final electrode.
The scientists claim that they have designed an electrode by using a simple and non-ionic surfactant, which is able to catalyze the oxidation of methanol at a higher current intensity.