The great promise of hydrogen fuel cells is their potential to take hydrogen generated by low cost solar power, and put it to work at moving your car from point A to point B – all with zero emissions. But, there’s a catch. The current technology relies on a tiny dose of platinum, which at current prices of $1800 per ounce has kept the cost of hydrogen fuel cells too high for the mass market. Now a team of scientists from Los Alamos National Laboratory has found a less expensive alternative, using low cost blend of iron, cobalt, and a form of carbon partly derived from polyaniline, a compound that was first discovered 150 years ago.
The Long Trail of Polyaniline
Polyaniline was first produced from indigo (the dye that puts the blue in blue jeans) in the 1840’s or the 1860’s, depending on who’s talking. In any case it took a while to catch on, but in the 1980’s polyaniline finally became of interest to researchers due to its high electrical conductivity, and the fact that it is relatively stable and easy to produce. In terms of alternative energy polyaniline shares something of a love triangle with phthalocyanines, which are also used in dying blue jeans, and are the subject of research as solar energy collectors.
Polyaniline in Hydrogen Fuel Cells
In a conventional hydrogen fuel cell, platinum is the preferred catalyst that sparks the production of electricity. The Los Alamos team found that their carbon-iron-cobalt substitute yielded currents comparable to platinum. It also compared well in other tests, such as durability when the fuel cell is cycled on and off, and efficiently converting hydrogen and oxygen into water. An inferior conversion process yields a large amount of hydrogen peroxide, an undesirable byproduct, aside from shortening the efficiency and lifespan of the fuel cell.
Next Steps to a Cheaper Fuel Cell
So far the researchers know that the new catalyst works, but they need to determine exactly how and why it works before it can be developed into a more efficient and durable product suitable for commercial development.
Image: Traffic jam by repres on flickr.com.
- Is That a Fuel Cell in Your Pocket, Or Are You Just Glad to See Me? (cleantechnica.com)