Structural Effects of 3D Inkjet‐Printed Ni(O)‐YSZ Pillared Electrodes on Performances of Solid Oxide Electrochemical Reactors

Abstract

Increasing densities of reaction sites for gaseous reactants in solid oxide electrochemical reactors (SOERs), is a key strategy for achieving enhanced performance in either fuel cell or electrolysis modes. Fabrication of 3D structured components in SOERs can enhance those densities of reaction sites, which is achieved by 3D inkjet printing with high reproducibility, having developed inks with appropriate properties. First, the effects of pillar geometries on SOER performances are predicted through numerical simulations, enabling subsequent 3D printing to focus on the more effective geometries. Herein, the study reports the results of experimental validation of those predictions by evaluating the electrochemical performances of cells with various heights of 3D inkjet‐printed Ni(O)‐ yttria stabilized zirconia (YSZ) pillars and YSZ pillars. Those measurements prove that increasing pillar heights generally increases SOER peak power densities in fuel cell mode and increased current densities at the thermoneutral potential (1.285 V) in steam electrolysis mode, as predicted by simulations. With increasing pillar heights, more limitations in performance enhancement are found with YSZ electrolyte pillars than with Ni‐YSZ pillars, again as predicted by simulations. The subsequent microstructural analysis of Ni‐YSZ pillars proves the suitability of the Ni(O)‐YSZ composite particle ink formulation and the reliability of 3D printing.

Comprehensive review and future perspectives: 3D printing technology for all types of solid oxide cells

“…In subsequent research, the team further advanced inkjet printing technology for pillar formation, optimising the fabrication processes for YSZ pillars and YSZ-NiO pillars with extended lengths [101].…”

“…In this study, simulations have demonstrated that when YSZ and Ni-YSZ pillars are optimised, the performance of fuel cells could potentially be enhanced by factors of 2.85 and 4.9, respectively (figure 20(e)). Experimental validation of these results has been attempted through inkjet printing [101].…”