Influence of gold nanoparticles on the up-conversion fluorescence in Sm3+

Fluorescence spectra of gold colloid containing samarium ions have been recorded and analyzed at room temperature. For gold colloids, two fluorescence emission peaks are observed at 443 nm and 745 rim. respectively when the corresponding excitation wavelength is fixed at 595 nm. When amount Of Sm-3' are added to gold colloids, the up-conversion emission peak at 443 nin increased greatly. Furthermore, increasing the gold colloids addition leads to the Up-conversion luminescent intensity increases in the early stage and then decreased. We believe the enhanced up-conversion are due to the energy transferred from the fluorescence from gold nanoparticles to Sm-3', and make the excited state absorption (ESA) in Sm-3' takes place. (c) 2005 Elsevier B.V. All rights reserved.