Effect of SnO₂ Nanocrystals on the Emission of Eu³⁺ Ions in Silica Matrix

Silica xerogels containing Eu³⁺ ions and SnO₂ nanocrystals were prepared in the sol‐gel process, and characterized by x‐ray diffraction (XRD) and photoluminescence spectra. Under the excitation at 393 nm, characteristic emission of Eu³⁺ ions at 614 nm was enhanced with increasing amount of SnO₂ nanocrystals. Moreover, when the Eu³⁺/SnO₂ co‐doped samples were excited at 345 nm, corresponding to the sideband of SnO₂ nanocrystals, the emission of Eu³⁺ ions at 614 nm was clearly observed, while no emission of Eu³⁺ ions for the Eu³⁺‐doped sample. It may be ascribed to the energy transfer from SnO₂ conduction band to Eu³⁺ conduction band. Further experimental results suggest that the energy transfer may be achieved through surface transition state.

Keywords:

• Eu³⁺ ions
• SnO₂ nanocrystals
• silica xerogels
• photoluminescence
• energy transfer

This work was financially supported by Excellent Young Teacher Program and Research Foundation of Returned Student Abroad, MOE of P. R. China. The authors also thank Shanghai Education Committee for support.