Over the years, fuel cells have been considered as a cleaner solution to meet future energy needs. Well, the catalysts used even in today’s state-of-the-art fuels cells may break down, inhibiting the chemical reaction that converts fuel into electricity. In an attempt to boost the efficacy of fuel cells, a team of engineers from the Yale School of Engineering and Applied Science has now created a new fuel cell catalyst system through nanowires. The developed catalyst can probably improve long-term performance by 2.4 times in comparison to today’s technology.
Scientists have fabricated the miniscule nanowires by an innovative metal alloy known as a bulk metallic glass (BMG). Since, these nanowires have high surface areas, they may expose more of the catalyst and simultaneously maintain longer than traditional fuel cell catalyst systems. The present day fuel cell technology seemingly uses carbon black as a support for platinum particles. Carbon black appears as an inexpensive and electrically conductive carbon material transporting electricity, while the platinum is the catalyst that drives the production of electricity.
“This is the introduction of a new class of materials that can be used as electrocatalysts. It’s a real step toward making fuel cells commercially viable and, ultimately, supplementing or replacing batteries in electronic devices,” commented André Taylor.
Greater the number of platinum particles the fuel is exposed to, the more electricity is allegedly generated. However, a major drawback of this method is that carbon black seems to be porous, so the platinum inside the inner pores are not be exposed. In fact, carbon black is also believed to corrode over time. For producing more efficient fuel cells, the active surface area of the catalyst has to be probably elevated. At 13 nanometers in scale, the developed BMG nanowires were apparently three times smaller than carbon black particles.
The nanowires’ long, thin shape supposedly gives them much more active surface area per mass than carbon black. Instead of sticking platinum particles onto a support material, the platinum into the nanowire alloy reportedly ensures that it continues to react with the fuel over time. It’s the nanowires’ unique chemical composition that purportedly makes it possible to shape them into such small rods through a hot-press method. As of now, the catalyst system has been tested for alcohol-based fuel cells, such as those using ethanol and methanol as fuel sources.
The research appears in the April issue of ACS Nano.