Influence of Ta2O5 Addition on Thermophysical Performance of Sm2Ce2O7

To investigate the influence of Ta2O5 addition on lattice-structure and thermophysical performance of Sm2Ce2O7, the (Sm1-xTax)2Ce2O7+x ceramics were synthesized exploring high-temperature fritting technology, the lattice-structures and thermophysical performances were evaluated. Results exhibit that pure oxides with onefold fluorite-type lattice are obtained. Because of the divergences in atomic weights and ionic radii between Ta5+ and Sm3+, thermal conductivities of synthesized oxides decrease with increasing Ta2O5 contents. Owning to the less ionic radius of Ta5+ than that of Sm3+, the thermal expansion coefficients are reduced with increasing Ta2O5 contents. The thermophysical performances of the synthesized compounds meet with the demands for heat-insulation coatings.