Citric–Nitrate Combustion Synthesis and Electrical Conductivity of the Sm³⁺ and Nd³⁺ Co‐Doped Ceria Electrolyte

Abstract

Nanocrystalline fluorite Ce 0.8 Sm x Nd 0.2Àx O 1.9 (x 5 0.2, 0.15, 0.1, 0.05, and 0) powders were prepared by a citric-nitrate combustion process and the grain sizes were determined to be 10-20 nm from X-ray diffraction patterns. Dense Ce 0.8 Sm x Nd 0.2Àx O 1.9 pellets were successfully prepared by sintering these fine powders at 14001, 15001, and 16001C, respectively. The scanning electron microscopy pictures showed that the grain size of the pellet sintered at 14001C was between 500 nm and 2 lm, while for the samples sintered at 16001C, the grains were coarser (6 lm). The electrical conductivity of the sample sintered at 14001C was as high as 0.012 S/cm at 5001C and the activation energy was determined to be 0.63 eV. The mechanism of improved electrical conductivity in this codoping ceria solid solution is discussed.

Solution combustion synthesis using furfuryl alcohol as fuel and a combustible solvent

“…[4][5][6][7] High surface area metal oxides and composites can be synthesised by SCS for a wide range of applications. [8][9][10] The conventional SCS involves dispersing a metal nitrate and a fuel in water to form a homogeneous aqueous solution. Upon heating, the non-reacting solvent, water needs to be evaporated before a self-propagating combustion takes place, resulting in the formation of a porous oxide.…”

Characterization of Nd and Sm Co-Doped CeO2-Based Systems

“…As reported in the * corresponding author; e-mail: aliye@istanbul.edu.tr previous studies [5][6][7], co-doping could enhance the ionic conductivity. Dopant ion, dopant concentration, oxygen vacancy concentration and local defect structure are the factors, which can influence the total ionic conductivity in doped CeO 2 [8,9].…”

“…To obtain pure doped CeO 2 powders, various techniques have been used such as citric-nitrate combustion [6] and sol-gel method [5,8], etc. Among these techniques, polyol method, which is generally used for producing metallic particles, could be employed to synthesize metal oxide particles.…”

Low temperature fabrication of dense gadolinia-doped ceria electrolyte with enhanced electrical conductivity

“…Ceria solid solution is widely recognized as a promising electrolyte for IT-SOFCs due to higher oxygen ionic conductivity and better chemical compatibility to electrode materials than conventional yttria stabilized zirconia (YSZ) [6][7][8][9][10][11][12][13]. However, one of the main difficulties encountered in application about ceria-based materials is to obtain densified electrolytes at low temperatures, which usually need to expose to high temperatures over 1600 o C when solid-state reactions are applied, leading to electrochemical performance degradation [14].…”