Improved ceria–carbonate composite electrolytes

It has been successfully demonstrated that the fuel cells using the ceria–carbonate composite as electrolytes have achieved excellent performances of 200–1150 W/cm2 at 300–600 °C. Previously it was reported these ceria–carbonate composite electrolytes have been prepared with two-step processes: step 1, prepare ion-doped ceria which was prepared usually through the wet-chemical co-precipitation process; step 2, mixing the doped ceria with carbonates in various compositions. We first report here to prepare the SDC–carbonate composites within one-step chemical co-precipitation process, i.e. mixing carbonates and preparing the SDC in the same process. The one-step process has provided a number of advantages: (i) to reduce the involved preparation processes to enhance the production, to make the produced materials in good quality control, more homogenous composites microstructure; (ii) as results, these composites showed also different micro-structures and electrical properties. It has significantly improved the ceria–carbonate conductivities and cause the superionic conduction at much lower temperatures; (iii) to reduce manufacturing costs also.