Washington, May 6 : Scientists have devised new materials that enable the manufacture of cheaper and more efficient methanol fuel cells, which are an efficient and sustainable alternative to fossil fuels.
Within the field of renewable energies, the scientific community is trying to develop fuel cells, capable of creating electrical energy from a chemical reaction between a fuel and oxygen.
Now, Jose E. Barranco, from University of the Basque Country, developed new metallic materials of an amorphous nature (disordered molecular structure) for use in direct methanol fuel cells.
Barranco chose methanol (a type of alcohol derived from methane gas) because it is a good option for charging fuel cells.
In order for the fuel cell to generate electricity, a chemical reaction called electro-oxidation has to take place and this, in turn, requires a catalyst to accelerate the process. his catalyst is inserted in the fuel cell membrane and, in the case of methanol, the basic accelerator is platinum, a scarce and expensive metal.
This is why the aim of Dr. Barranco's thesis was to devise a catalyst composed of a metal alloy in which the amount of platinum is significantly reduced.
After investigating the composition of numerous metals, Dr. Barranco made alloys that enabled the reduction of the proportion of platinum to 1%.
These alloys have the unique property of converting molecules of carbon monoxide (CO) into carbon dioxide (CO2) efficiently.
The CO2, being gaseous, does not adhere to the catalyst which in the long term favours the catalytic process.
According to Dr. Barranco, this means that the methanol fuel cell will emit a small quantity of CO2, which is easily tolerable by nature given that this can be incorporated into the photosynthesis cycle of plants.
Once the suitable catalyst was found, Dr. Barranco set out to increase its efficiency.
The conclusions of his thesis point to the fact that, if the platinum alloy is structured amorphously, its electrical conduction properties are enhanced and it undergoes less corrosion.
For the catalyst made on this basis of amorphous metal alloys to be incorporated into the fuel cell membrane, Dr. Barranco decided to change its form.
The result is a very fine powder that is placed in a container to "spray paint" the membrane. As it is a substance made of minute particles, the operating capacity of the catalyst is enhanced by 9 to 13 times.
Taking into account that the catalyst improves the efficiency of the cell by more than 50%, this new material is a giant step forward in fuel cell research.