Abstract
The current work principally treats the significant aspects of solid electrolytes based on cerium oxide in the absence and presence of potassium bicarbonate. The classic oxide electrolyteCe0.7La0.15Ca0.15O2-delta (LCDC) and the bicarbonate nanocomposite electrolyteCe0.7La0.15Ca0.15O(2)-delta @KHCO3 (LCDC@KHC) are synthesized separately via self-combustion and co-precipitation techniques. Structural, thermal, electro-morphological and electrochemical properties of pure LCDC and nanocomposite material LCDC@KHC are carefully examined. In particular, the influence of the heavily coupling amongst LCDC oxide and KHCO3 bicarbonate on the microstructures and ionic conductivities of KHCO3-coated nanocrystalline LCDC is studied by TG/DTA, Raman, FEGSEM and AC impedance spectroscopy. Thermal analyses show that the LCDC@KHC nacomposite is stable at a temperature below 122 degrees C. Beyond this temperature, the LCDC@KHCO3 nanocomposite is transformed into a LCDC@(KHCO3/K2CO3) nanocomposite. XRD data confirms that the LCDC phase and the various nanocomposite materials LCDC@KHC, sintering at different temperatures, adopt the fluorite structure. Lattice parameters and bond lengths are determined by Rietveld refinement. The ionic conductivity of bicarbonate nanocomposite electrolyte LCDC@KHC is 100 to 1000 times higher than that of the novel classic electrolyte LCDC. The remarkable enhancement of conductivity as a function of temperature rise is correlated to the presence of potassium in two forms: bicarbonate and carbonate in the LCDC@(KHCO3/K2CO3) nanocomposite electrolyte.