Nanomesh electrode boosts hydrogen production

Today, two commercially available options exist for megawatt-scale hydrogen production. The oldest method is alkaline water electrolysis (AWE), in which water is split into hydrogen and oxygen by sending an electrical current through an alkaline solution. The setup features two electrodes, separated by a membrane that allows ions, but not the gasses that bubble up at the electrodes, to pass. Proton exchange membrane electrolysis (PEM) is conceptually similar but involves an acidic solution, a different type of membrane and typically the use of a more expensive type of catalyst to help the water-splitting reaction along.

Both technologies face challenges that need to be overcome to improve the competitiveness of large-scale production of green hydrogen. In simple terms, as many electrons as possible need to be added to or extracted from water molecules on the electrode’s surface in any given time frame. This means increasing the electrode surface area, but not at the expense of inhibiting the flow of gaseous reaction products to and from the reaction sites. Additionally, such porous electrode structures need to be manufacturable in a scalable way.