Proton Exchange Membrane Fuel Cells (PEMFC) are the energy source of the future. More commonly known as hydrogen fuel cells, PEMFCs convert hydrogen and oxygen into electrical output. Since the only byproducts are heat and water, PEMFCs would be much more environmentally-friendly than combustion engines. But, PEMFCs have been held back from the mainstream market because they require a very rare material – platinum.
Platinum electrodes are required to catalyze the reaction between hydrogen and oxygen to produce electricity. There are other metals that can catalyze such a reaction, but they cannot withstand the acidic environment of the PEMFC. Platinum, on the other hand, has stable electrical conductivity and is extremely resistant to oxidation and corrosion – even in high temperatures.
During the ongoing research for PEMFCs, one of the major goals has been to find another suitable catalyst instead of relying on platinum. Recently, researchers from the Technical University of Denmark have made some headway using a new type iron carbide and carbon-based catalyst.
Ordinarily, iron carbide would dissolve in the acidic environment of the PEMFC. But it’s protected by a layer of graphene – a highly resilient form of carbon. The Danish team discovered that the iron carbide could be protected from the acidic environment of the PEMFC by covering it in a very thin layer of rolled up graphene. Even though the graphene protects the iron carbide from the acid, it does not inhibit the catalytic activity.
There is still a lot of testing and research to be done, but if platinum can be replaced as a catalyst in fuel cells, there will be more available for other applications, such as anticancer drugs, spark plugs, and more.