Laserless Additive Manufacturing of Membrane Electrode Assemblies

New electrode geometries with high porosities are of great interest for electrochemical processes. By using additive manufacturing design, the limitations of conventional production processes can be overcome. The presented laserless additive manufacturing method allows us to print any geometrical shape using metal and ceramic pastes. Here, the paste compounds were 70 vol% nanocellulose and 30 vol% metal/ceramic powder. Two different electrode geometries were printed, the disc and the gyroid. Furthermore, two different geometries of membrane electrode assemblies (MEAs) were printed: a flat and a tubular MEA. Following printing, the green samples were sintered. Afterwards, the disc electrode and flat membrane electrode assembly were coated with IrO2 (anode) and Pt (cathode) catalysts. The coated samples were assembled into a polymeric MEA water electrolyzer (pMEA) and into a ceramic MEA water electrolyzer (cMEA) to evaluate their potentials. Print your own electrolyzer: Paste extrusion can be used to print complex geometries from metals, which can then be used as an electrode. Combining the complex electrode geometries with a separator results in a membrane electrode assembly. A showcase study is presented, in which a 3D‐printed SiO2 layer (as the porous separator) is sandwiched between catalyst‐coated titanium layers. These are then built into a 3D‐printed water electrolyzer (see picture).