| 内容提要: |
TiO2, as a photocatalyst, has attracted
substantial interest. We fabricate the quantum dot self-decorated and
defect-free anatase nanosheets, for the first time, using an in situ
hydrothermal strategy. The long-time hydrothermal strategy and subsequent
defect healing are the keys to obtain defect-free nanosheets decorated with TiO2
quantum dots. The size of nanosheets progressively increases with t, but the
{001} percentage almost remains unchanged (81–83%). The band structure of
quantum dots matches that of the clean nanosheets very well. In this structure,
the photo-excited electrons can transfer from {001}facet to the quantum dots,
providing a new and more effective charge separation and transfer pathway over
the nanosheet surfaces, and promote the photoactivity significantly, due to the
well matched band structures. And the surface Ti3+ defects suppress
the photoactivity and could be removed by hydrothermal treatment or
calcination. |