Fuel cells use hydrogen combined with atmospheric oxygen to produce electricity and the only byproduct is water vapor. Consequently, they hold great promise as a clean and renewable technology for vehicles, considering how combustion engines use nonrenewable fossil fuels and emit substances responsible for global warming and atmospheric pollution. However, because fuel cells are reliant on platinum as a catalyst for the chemical reaction that powers them, the fuel cells and the cars powered by them have remained too expensive for widespread adoption.
But in a study published today in Science, the research team showed how using jagged-shaped platinum nanowires increases their efficiency as a catalyst. Manufacturing nanowires with jagged surfaces, rather than smooth, creates new types of highly active sites that can significantly reduce the reaction barrier and speed up the oxygen reduction reaction. And, the thin body of the nanowire ensures most of the platinum atoms are exposed on the surface to actively participate in the reaction instead of being embedded inside the body and making little contribution to the reaction. All of that results in a reduction in the amount of platinum used, and therefore the cost, while at the same ramping up the reaction efficiency and power generation rate.