Preparation, formation mechanism and photocatalysis of ultrathin mesoporous single-crystal-like CeO2 nanosheets.

For the first time we synthesized mesoporous CeO2 nanosheets with single-crystal-like, ultrathin and uniform-sized structures through the thermal decomposition of specially prepared intermediates of Ce(OH)CO3 nanosheets. The resulting single-crystal-like CeO2 porous nanosheets are only 2.4 nm thick, as measured by AFM. BET analysis indicated that the pores of the nanosheets were centered at 3.7 nm. A novel structure transformation mechanism from 1D to 0D, then to a 2D assembly was clearly revealed. Moreover, such ultrathin CeO2 porous nanosheets exhibited much higher photocatalytic activity for dye degradation than that of polycrystalline CeO2 nanoparticles.