Synthesis of ceria-based ceramics by combustion technique

Ce_1-xGd_x/Sm_xO_2-δ(x=0.1, 0.2) powders were prepared by combustion method using corresponding metallic nitrates and different fuels (α-alanine, oxamic hydrazide and tartaric acid). Ce_1-xGd_x/Sm_xO_2-δ powders were formed direct from combustion reaction in one single step when oxamic hydrazide or α-alanine is used as fuel. In the case of tartarate-based precursors, the fluorite phase has been formed by calcining the as-prepared powders (the powders resulted in the combustion reaction) at 500 °C, 3h. The structure and thermal decomposition of the precursors, isolated before the ignition of the reaction mixture, were studied by FTIR spectroscopy and thermal analysis (DTA-TG). The oxide powders were investigated by X-ray diffraction and scanning electron microscopy. Densification of Ce _1-xGd_x/Sm_xO_2-δ (x=0.1, 0.2) ceramic bodies was studied function of the doping ion and sintering conditions.