What are the reactions involved in the direct methanol fuel cell?
Reaction. The DMFC relies upon the oxidation of methanol on a catalyst layer to form carbon dioxide. Water is consumed at the anode and produced at the cathode. Protons (H+) are transported across the proton exchange membrane – often made from Nafion – to the cathode where they react with oxygen to produce water.
What are the disadvantages of methanol fuel cell?
The limitations for direct methanol fuel cells are (1) methanol crossover from the anode to the cathode across the membrane separator, (2) carbon monoxide poisoning, (3) high polarization of the anode for the oxidation of methanol, and (3) systems design.
What is the electrolyte used in direct methanol fuel cell?
These cells use platinum-based catalysts to promote the electrode reactions, and a solid acidic proton conducting polymer electrolyte, often Du Pont’s Nafion® perfluorinated sulphonic acid-type materials.
Why don’t we use pure ethanol for cars?
Ethanol is bad for cold-starting, because it doesn’t burn as quickly as gasoline. (It has a higher octane, if you’re interested.) Pure ethanol would be useless as fuel in the winter months. There are no passenger cars designed to take E100 (but some racing cars are) so it could damage your car engine.
How do ethanol fuel cells work?
Ethanol is oxidized at the anode, in the presence of steam and a platinum catalyst, to produce hydrogen, carbon dioxide, and electrons. Because ethanol is hydrogen-rich, it produces more energy per kilogram than do fuels like methanol or pure hydrogen. The result is more energy per volume of fuel.
What is the power output of direct methanol fuel cell?
We have developed 1 kW output direct methanol fuel cell (DMFC) successfully, which is the highest output level in the world in this kind of fuel cell. Methanol, the fuel of DMFCs, has such advantage features as easy handling, high storage stability and high energy storage capability.
What are the advantages of using methanol as a fuel?
Methanol can be an alternative to conventional transportation fuels. The benefits of methanol include: Lower production costs—Methanol is cheap to produce relative to other alternative fuels. Improved safety—Methanol has a lower risk of flammability compared to gasoline.
How does methanol react with oxygen in a fuel cell?
In a fuel cell employing an acid electrolyte, methanol is directly oxidized to carbon dioxide at the anode: The thermodynamic potential ( E0) for reaction (1) calculated from the standard chemical potentials at 25 °C is 0.03 V versus SHE. At the cathode, oxygen gas combines with the protons and electrons and is reduced to water:
What are the disadvantages of direct methanol fuel cells (DMFC)?
A main drawback of direct methanol fuel cells (DMFCs) is the very sluggish anode reaction, which coupled with the inefficient cathode reaction, gives rise to low overall performance, particularly at low temperatures.
What happens when methanol reacts with platinum?
Reaction. During the methanol oxidation reaction carbon monoxide (CO) is formed, which strongly adsorbs onto the platinum catalyst, reducing the number of available reaction sites and thus the performance of the cell. The addition of other metals, such as ruthenium or gold, to the platinum catalyst tends to ameliorate this problem.
What are the ancillary units of methanol fuel cells?
Ancillary units. A direct methanol fuel cell is usually part of a larger system including all the ancillary units that permit its operation. Compared to most other types of fuel cells, the ancillary system of DMFCs is relatively complex.