Densification of cerium gadolinium oxide by laser treatment

International audienceIn single-chamber solid oxide fuel cells (SC-SOFC), anode and cathode are placed in a gas chamber where they are exposed to a fuel/air mixture. Similarly to conventional dual-chamber SOFC, the anode and the cathode are separated by an electrolyte, but in the SC-SOFC configuration it does not play tightness role between compartments. For this reason, the electrolyte can be made by screen printing, a technique particularly appropriate for preparing thick porous layers. However, it is necessary to have a diffusion barrier to prevent the transportation of hydrogen produced locally at the anode to the cathode that reduces fuel cell performances. This study aims to obtain directly a diffusion barrier through the surface densification of the electrolyte by a laser treatment. The material chosen for the electrolyte was cerium gadolinium oxide Ce0,9Gd0,1O1,95 (CGO) which is deposited by screen printing on a composite anode NiO-CGO. KrF excimer laser and Yb fiber laser irradiations were used to modify the density of the electrolyte coating. Different tests were performed with the variation of energy density and number of pulses. Microstructural characterizations confirm the densification on the surface of the electrolyte for appropriate experimental conditions. The effect of laser treatment on SC-SOFC performances will also be discussed