To free ourselves from the use of fossil fuels that are highly polluting, life-threatening and not easily regenerated, new technologies are being developed to obtain alternative energy sources more efficiently. Among these technologies, there is the option to improve the performance of solid oxide fuel cells (SOFCs) to make them highly energy efficient. Solid oxide fuel cells (SOFCs) have attracted much attention because they are environmentally benign, sustainable, generate low emissions and have relative low cost. However, conventional SOFCs with yttria-stabilized zirconia (YSZ) electrolyte require high operating temperatures (800-1000°C), which often lead to material degradation problems. Given that the greatest disadvantage of SOFCs is their high operating temperature, samples of CeO2 were synthesized by spray pyrolysis method and doped with Sm2O3 and Eu2O3 to improve the ionic conductivity of the electrolyte so that it can operate at lower temperatures without losing its efficiency. The samples were analyzed using SEM, EDS, TEM. Further research will be made by small angle DRX, AFM, EIS and a prototype will be built to test the working temperature of the electrolyte.