Tailoring Pore Networks – Gas Diffusion Electrodes via Additive Manufacturing

Abstract

Additive manufacturing (AM) is a promising alternative to conventional electrode production due to its high freedom of design, excellent reproducibility, and a manifold choice of metals serving as substrates or even electrocatalysts in various electrochemical reactions. Nonetheless, porous gas diffusion electrodes (GDEs) have not been fabricated by AM due to the required resolution of the pore network in the micron to submicron range. Herein, the single-step fabrication of GDEs via AM is demonstrated for the first time. Selective laser melting is used to control the porosity, the pore diameter, and the electrochemically active surface area of the generated pore network by engineering the laser hatching strategy. In this way, the electrocatalytic activity of the fabricated GDEs is tuned for CO2 electroreduction. The CO2 reduction reaction is amplified whilst the competing hydrogen evolution reaction is mitigated at high current densities of 100 mA cm−2. The presented method is a step further towards the production of next-generation electrodes with tailored gas diffusion layers, thereby boosting electrode performance in a wide range of electrochemical applications.