Hydrothermal synthesis of Co, Cu dual doped CeO2 based nanoceramic electrolyte material and evaluation of its physical, electrochemical and dielectric properties for LTSOFC

Abstract

Co, Cu dual doped ceria nanoceramic electrolyte material with the composition of Ce_0.50Co_0.25Cu_0.25O_2-δ (CCCO) was synthesized by a simple hydrothermal route using stoichiometric amount of metal nitrates with sodium hydroxide precipitant. The properties of the prepared nano-ceramic particles were systematically evaluated by TGA, XRD, FTIR, EDAX, SEM and TEM. The XRD data confirmed the formation of FCC structure. FTIR data revealed the existence of M − O band in the sample. SEM and TEM photographs showed the manifestation of nano-grains in the sample. Presence of appropriate elements with atomic weight % was confirmed by the EDAX data. The circular sintered CCCO disk components were subjected to impedance and dielectric studies from room temperature to 540 ^oC in air. The oxide ion conductivity for the electrolyte was enhanced systematically from room temperature and attained a maximum value of 6.4583x10^-4 Scm^-1 at 540 ^oC. The activation energy was found to be 0.40 eV at the optimum temperature (540 ^oC). The dielectric constant of the sintered specimen was slowly enhanced with raise in temperature at varied frequency ranges. From the results, it was found that the proposed composition may be a better choice as an alternate electrolyte material for low temperature solid oxide fuel cell (LTSOFC) application.