| abstract |
It has been discovered that a composite material comprising an amorphous porous material and a nanocrystalline material in the pores becomes a UV absorber. The porous material is a matrix of pores that act as a scaffold for the nanocrystalline material. The particles of nanocrystalline material have been separated, which means that the particles are not connected 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 protrude from 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 size ranges from 2 to about 100 nm on its longest axis and the aspect ratio is from about 1 to about 1.5. |