Fabrication of rare-earth-oxide aerogel targets with low density

Low-density high-Z oxide aerogels are easy to shrink or crack due to the formation of the end group of metal-oxygen double bond in their precursors solution. Rare-earth oxide aerogels were prepared via coordination environment adjustment and dispersed inorganic sol-gel method. Lanthana-based aerogel and yttria-based aerogel exhibit good formability, and have the lowest densities of about 0.05 g·cm^-3 and 0.06 g·cm^-3 respectively. Their main compositions are hexagonal phase La(OH)₃ and Y(OH)₃ respectively, while the ions are coordinated with carboxyl groups in polyacrylic acid via bridge mode. Both the two kinds of aerogels are obviously composed of hierarchical microstructure, exhibiting similar spherical secondary structure but different primary structure composed of fiber and sheet/sphere, respectively. Their specific surface areas are 229.1 m²·g^-1 and 229.6 m²·g^-1, respectively. Given the low density and nanoscale homogeneity of the rare-earth oxide aerogels prepared via this method, they exhibit application potentials in the field of backlight targets. (authors)