Carbon usually plays a “supportive” role to platinum in many catalytic processes, particularly in electrode structures of fuel cells and batteries. Even so, platinum particles often “wander off” their anchored positions, causing severe degradation and adding further cost to the already costly device.
Can carbon rise to the catalytic challenges without platinum? By closely coupled fundamental simulations and innovative synthesis, researchers from Prof. Xiao Guo’s group have developed a cost-effective and durable electrocatalyst, based on a phosphorus-nitrogen co-doped graphene framework (PNGF) – the results have just been published in Energy and Environmental Science [Chai et al, Energy and Environmental Science, 2017, 10, 1186-1195; DOI: 10.1039/C6EE03446B ].
Simulations pin-point effective sites for catalysis, and synthesis approaches were tuned to enrich such sites. The carbon-based catalyst not only outperforms platinum in the oxygen reduction reaction (ORR), a key step in the power supply of fuel cells and metal-air batteries, but also the state-of-the-art iridium-based catalyst for the reversible oxygen evolution reaction (OER) (see figure below).
This highly efficient bifunctionality is beyond the reach of either of the more expensive noble-metal counterparts. Moreover, without foreign particles to support, the catalyst is much more stable and durable. This design strategy, synthesis approach and the efficient catalyst offer great opportunities for the development of highly cost-effective electrochemical devices across a range of scales in mobile phones, lap-tops, electric vehicles and even the electricity grids.
For further information, please contact Professor Z. X. Guo via email: z.x.guo@ucl.ac.uk.