You can hardly find a consumer electronics user who would not be irritated by problems with power supply. The batteries run out quickly and require continuous replacements or take a long time charging. Fuel cells could significantly improve the comfort of using electronic devices. Their commercialization, however, is hampered by many technological problems. A new catalyst developed at the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw represents a substantial milestone on the way to dissemination of cheap, durable, light and environment friendly fuel cells powered by formic acid.
Fuel cell is a device converting chemical energy into electric power. The current is generated directly due to fuel combustion in the presence of catalysts used on the anode and the cathode of the fuel cell. "Theoretical efficiency of conversion of chemical energy into electric power in the cells can reach even one hundred percent. The best present fuel cells, powered by hydrogen, reach up to 60% in real life. For comparison, the efficiency of low-compression engines is as low as 20%," says Dr Andrzej Borodzinski from the IPC PAS.
The biggest obstacle to dissemination of hydrogen fuels is the storage of hydrogen. The issue turned out to be extremely technologically challenging and still is waiting for satisfactory solutions. An alternative to fuel cells powered by pure hydrogen is the methanol fuel cell technology. Methanol, however, is toxic and the methanol powered fuel cells must be produced with expensive platinum based catalysts. Moreover, methanol fuel cells have low power and are operated at a relatively high and so potentially hazardous temperature (approximately 90°C).
An alternative solution is formic acid fuel cells. In this case, the reactions occur at room temperature, and the efficiency and power of these fuel cells are clearly higher than those for methanol ones. In addition, formic acid is easy to store and transport. To have, however, formic acid fuel cell stable in operation you need an efficient and durable catalyst.
"The catalyst developed by us has initially lower activity then the existing catalysts made of pure palladium. The difference disappears, however, already after two hours of operation. And further it is only better. Our catalyst is stable in operation, whereas the activity of a pure palladium-based catalyst decreases in time," says Dr Borodzinski.
An advantage of the catalyst developed in the IPC PAS, particularly important from the economic point of view, is that it preserves its properties while operated in formic acid of low purity. Such formic acid can be easily produced in large quantities, also from biomass, so the fuel for new fuel cells would be very cheap.
Formic acid produced from biomass would be a fully environment friendly fuel. The reactions involving formic acid in fuel cells generate as products water and carbon dioxide. The latter is, as a matter of fact, a greenhouse gas, but the biomass is obtained from plants which use carbon dioxide for their growth. As a result, formic acid produced from biomass and consumed in fuel cells would not change the content of carbon dioxide in atmospheric air. The risk of natural environment contamination by formic acid is also low.
Formic acid fuel cells would find numerous applications. They would be particularly suitable in portable electronic devices -- mobile phones, laptops or GPS-based devices. They could also be installed as power supply sources in vehicles, from wheelchairs through electric bicycles up to yachts.
At the IPC PAS the research is being undertaken on the first batteries based on formic acid fuel cells. The researchers expect that a prototype of a commercial device should be ready within a couple of years.
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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Institute of Physical Chemistry of the Polish Academy of Sciences, via AlphaGalileo.
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