Rochester, New York – Researchers at the University of Rochester in New York have created long platinum “nanowires” that they say could soon lead to the development of commercially viable fuel cells. The new wires should provide significant increases in the longevity and efficiency of fuel cells.
“People have been working on developing fuel cells for decades,” said James Li, lead author of the study. “But the technology is still not being commercialized. Platinum is expensive, and the standard approach for using it in fuel cells is far from ideal. These nanowires are a key step toward better solutions.”
The wires, made by a process known as electrospinning, are thousands of times longer than any previous wires, and are long enough to create the first self-supporting “web” of pure platinum that can serve as an electrode in a fuel cell.
A catalyst in a fuel cell facilitiates the reaction of hydrogen and oxygen, splitting compressed hydrogen fuel into electrons and acidic hydrogen ions. Platinum has been the primary material used in the catalysts because of its ability to withstand the harsh acidic environment, and because its energy efficiency is substantially greater than that of cheaper metals such as nickel. Prior efforts in making catalysts have relied heavily on platinum nanoparticles, which have the disadvantage of the metal’s high cost.
The wires also overcome the problem of inefficiency due to a smaller surface area with nanoparticles, and with loss of particles as they do not attach well to the carbon structure used to hold nanoparticles in place. The wires are fixed in place and need no additional support, and platinum will no longer be lost during normal fuel cell operation.
“The reason people have not come to nanowires before is that it’s very hard to make them,” Li said. “The parameters affecting the morphology of the wires are complex. And when they are not sufficiently long, they behave the same as nanoparticles. With platinum being so costly, it’s quite important that none of it goes to waste when making a fuel cell.”