| abstract |
A composite material comprising an amorphous, porous material with nanocrystalline material in its pores has been found to be a UV absorber. The porous material is a matrix of pores that act as a scaffold for the nanocrystalline material. The particles of the nanocrystalline material are isolated, which mean that they do not connect to each other. In some embodiments, the nanocrystalline material is completely inside the pores of the porous material. In some embodiments, the nanocrystalline material may stick out of some or all of the pores of the porous material. In some embodiments, the nanocrystalline material is a cerium oxide material. In some embodiments, the nanocrystallite ranges in size from 2 to about 100 nm on its longest axis, with an aspect ratio from about 1 to about 1.5. |