Cobalt-Zirconia coated monoliths fabricated by Direct Ink Writing for catalytic applications

Direct Ink Writing (DIW) is a promising technique for fabricating ceramic catalysts with complex geometries and enhanced catalytic performances, but these still require overcoming some challenges to maximize their catalytic and mechanical functionality. In this work, DIW yttria-doped zirconia (YDZ) catalysts were coated with a Co/YDZ catalyst layer. Two configurations based on a dense monolith and a porous one sintered at 1450ºC and 1300ºC were fabricated through DIW, using optimal rheological hydrogel-inks, to investigate the effect of porosity on the mechanical and catalytic performance in the ethanol steam reforming reaction. The monolith sintered at 1450°C achieved the best mechanical and catalytic performance, as it presented the highest Co concentration (2.3 at%) at the catalyst layer. In addition, this monolith exhibited excellent mechanical properties at the interface between contiguous filaments in the multilayer structure. Therefore, this simple approach is a promising method to produce enhanced catalytically and mechanically robust monoliths.