Electrocatalyst approaches and challenges for automotive fuel cells

Although automotive fuel-cell catalyst development has come a long way in the past fifteen years, more research is needed for oxygen reduction electrocatalysts to be successfully commercialized. In the face of dwindling oil reserves and concerns about climate change, vehicles powered by fuel cells that use hydrogen from renewable sources and emit only water seem ideal. Small test fleets of fuel-cell vehicles have shown impressive performances, but in this Review Mark Debe reminds us that significant obstacles need to be overcome before the technology becomes genuinely practical. In particular, it will not be enough to develop oxygen-reduction electrocatalysts, the crucial components at the heart of fuel cells, with high activity. As important — and more challenging — is the need to ensure that these catalysts are highly durable, fault tolerant and can be mass-produced with high yields and exceptional quality. Many of the catalyst systems currently being explored seem unlikely to meet these criteria. Fuel cells powered by hydrogen from secure and renewable sources are the ideal solution for non-polluting vehicles, and extensive research and development on all aspects of this technology over the past fifteen years has delivered prototype cars with impressive performances. But taking the step towards successful commercialization requires oxygen reduction electrocatalysts—crucial components at the heart of fuel cells—that meet exacting performance targets. In addition, these catalyst systems will need to be highly durable, fault-tolerant and amenable to high-volume production with high yields and exceptional quality. Not all the catalyst approaches currently being pursued will meet those demands.