화학공학소재연구정보센터
Materials Research Bulletin, Vol.108, 10-15, 2018
Tunable upconversion emission of Ho3+/Yb3+-doped single beta-NaYF4 microrod
In this work, a series of hexagonal phase NaYF4: Yb3+/Ho3+ microrods have been successfully synthesized through hydrothermal methods, and their optical properties studied by a confocal microscope equipment with a 980 nm laser. An intense green and red upconversion emissions with candy-like emission pattern are observed from a single NaYF4: Yb3+/Ho3+ microrod. As the codoping CO3+ ion concentrations increases from 0% to 12% in the microrods, the interesting phenomenon that fluorescence emission of Ho3+ ion is tuned green to red emission has been obtained. The red-to-green ratio emission of Ho3+ ions is enhanced about 11-fold, which is due to the two efficient cross-relaxation processes between Ho3+ and Ce3+ ions, which leading to the populations increase of the F-5(5) state. The possible upconversion emission mechanisms are discussed based on the emission spectra of Ho3+ ions. The current study suggests that the NaYF4: Yb3+/Ho3+ microrods with the strong red upconversion emission may have great potential applications in micro-fiber laser, multicolor display, microoptoelectronic device.y