In principle, seawater offers an ideal source of hydrogen for clean energy. But, in practice, the electricity used to extract the hydrogen from seawater produces unwanted by-products (from the salt in the water) that poison the catalyst and shut down the process. By using stacked graphene sheets (sheets of carbon atoms similar to those in pencil lead, each as thin as a thousandth of a hair), a team of researchers, led by McGill professor Marta Cerruti of the Department of Materials Engineering, have now built a porous, three-dimensional, electrode in the form of a sponge that has successfully separated the water from the unwanted chemical compounds. The next challenge will be scaling up the process to mass produce the electrodes, which could also potentially be used for other reactions where it is important to prevent interference from certain molecules.

"Selective Catalytic Electro-Oxidation of Water with Cobalt Oxide in Ion Impermeable Reduced Graphene Oxide Porous Electrodes" by Gabriele Capilli et al.was published in ACS nano.