Research into hydrogen fuel cells has been focusing lately on reducing their cost, in the tens of thousands of dollars.
For a while now, the accepted best-performing catalyst, both in terms of efficiency and lifespan, has been platinum. Unfortunately, platinum is more expensive than gold, due to its rarity. The current General Motors hydrogen fuel cell uses some 30g of the stuff, costing over $40,000 in platinum alone.
Research into a number of materials has led to discoveries that other molecules, including metals and non-metals, could serve as a viable replacement for expensive platinum. Such a development could make hydrogen fuel cells more affordable, causing prices of hydrogen fuel cell vehicles and backup power supplies to decrease significantly.
Research is ongoing in many laboratories around the world, including Ulsan National Institute of Science and Technology [UNIST] in South Korea. Taking inspiration from biology, UNIST researchers developed an iron phthalocyanine [FePc] carbon nanotube catalyst that is more efficient than platinum-based catalysts and just as durable. Iron phthalocyanine is very similar in structure to the porphyrins that make up hemoglobin in red blood cells.
By growing FePc structures on the sides of carbon nanotubes, UNIST researchers have been able to create a synthetic, non-metallic alternative to the expensive platinum catalysts currently in use. The FePc structures, on their own, are already more efficient than platinum. The increased conductivity of the carbon nanotubes is also more efficient. And could have other applications, aside from hydrogen fuel cells, including metal-air batteries, photovoltaic solar cells, and others.