Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8017152 | Materials Letters | 2016 | 4 Pages |
Abstract
NaYF4:Yb3+,Tm3+/CdSe nanoheterostructures were synthesized by an improved two-step wet-chemical route. Upon the excitation from a 980-nm near-infrared (NIR) laser, an intense 797Â nm NIR emission from Tm3+ ions was observed in the nanoheterostructures while neither ultraviolet (UV) nor blue emissions of Tm3+ ions appeared in the upconversion (UC) spectrum. It indicated that the energy transfer (ET) occurred between NaYF4:Yb3+,Tm3+ and CdSe. Under 980Â nm irradiation, the excitation energy absorbed by Yb3+ ions transferred to Tm3+ ions successively, then transferred to CdSe partially from the 1G4 state of Tm3+ ions, and finally the excited CdSe returns the energy back to the 3F2,3 levels of Tm3+ ions. Both the excitation (980Â nm) and the emission (797Â nm) are located in the NIR spectral range (700-1100Â nm) that is referred as the “optical window” of biological tissues. Therefore, the nanoheterostructures could have great potential in applications of biology and biomedicine.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Nanotechnology
Authors
Xueqing Bi, Guanghui He, Weihua Di, Weiping Qin,