The research team, involving scientists from Queen Mary University of London and University College London (UCL), showed that a new type of graphene-based catalyst was more durable than commercially available catalysts and matched their performance. The study is published in the journal Nanoscale. Scientists produced graphene via a special, scalable technique and used it to develop hydrogen fuel cell catalysts. Hydrogen fuel cells convert chemical energy into electrical power by combining hydrogen and oxygen with the aid of catalysts. As the only by-product of the reaction is water, they provide an efficient and environmentally friendly power source.
Platinum is the most widely used catalyst for these fuel cells, but its high cost is a big problem for the commercialisation of hydrogen fuel cells. To address this issue, commercial catalysts are typically made by decorating tiny nanoparticles of platinum onto a cheaper carbon support, however the poor durability of the material greatly reduces the lifetime of current fuel cells.
The technique described in the study produces high-quality graphene decorated with platinum nanoparticles in a one-pot synthesis. This process could be scaled up for mass production, opening up the use of graphene-based catalysts for widespread energy applications.
The researchers confirmed the durability of the graphene-based catalyst using a type of test based on those recommended by the US Department of Energy (DoE), known as accelerated stress tests. Accelerated stress tests deliberately stress the catalyst rapidly over many cycles in a short space of time, allowing scientists to assess the stability of new materials without having to use them in an operational fuel cell over a period of months or years.
Using these tests, the scientists showed that loss in activity over the same testing period was around 30 per cent lower in the newly developed graphene-based catalyst, compared with commercial catalysts.
