Ruthenium-loaded titania nanotube arrays as catalysts for the hydrogen evolution reaction in alkaline membrane electrolysis

In the present work, we introduce a new electrocatalyst for the hydrogen evolution reaction to be used for alkaline membrane water electrolysis. The new catalyst uses ruthenium as the active phase and titania nanotube arrays, grown onto a non-woven titanium transport layer, as dual-scale porosity support. The original synthetic strategy of the catalyst is reported along with the fundamental characterization of the material. The functionality of the catalyst is evaluated by cyclic voltammetry and linear sweep voltammetry to determine the hydrogen evolution reaction activity of samples with variable loading, to benchmark with state-of-the-art materials. Finally, we present the results of the cathodes when used in a full alkaline membrane electrolyzer. The device is able to deliver a current density that exceed 1 A cm−2 at less than 2 V with Ru loadings lower than 50 μg cm−2. Accordingly, this novel electrode structure with ultralow PGM loading shows an outstanding perspective for the application in alkaline membrane electrolysers, with the added benefit of being easy to handle.