Structural studies on the gadolinium doped nanoceria prepared by combustion synthesis

• The results showed that the prepared nanopowders have a mesoporous structure.
• The existence of structural distortion in particles containing mesopores was shown.
• Mesopores can be potential sites for segregation of dopants and oxygen vacancies.

Nanosized Ce1−xGdxO2−x/2 (x=0.1, 0.2 and 0.3) with different stoichiometric compositions was synthesized by the self-sustaining combustion method and calcined at 700 °C for 2 h. Nitrogen adsorption–desorption isotherm measurements showed that both the as-synthesized and calcined nanopowders were of a mesoporous structure with an average pore diameter of about 4 nm. Structural characterizations of such nanopowders were carried out using X-ray diffraction (XRD) and high-resolution electron transmission microscopy (HRTEM), which showed that the powders were gadolinium doped ceria solid solutions with crystallite sizes of less than 30 nm. Furthermore, an analysis of HRTEM images revealed the existence of structural distortion and dislocations in the nanoparticles containing the mesopores.