Research on photoluminescence of Nd3+ doped NaYF4:Yb, Er/Tm upconversion nanoparticles

Strong absorption of 980 nm wavelength light by biological tissues results in the limited application of Yb/Er or Yb/Tm doped NaYF4 upconversion nanoparticles. 800 nm excited NaYF4:Yb, Er/Tm nanoparticles doped with Nd3+ ions are reported. By comparing the photoluminescence spectra of different structured nanoparticles incorporated with Nd3+ ions, it is found that the emission intensity by 800 nm laser of core/shell structured NaYF4:Yb3+ 20%, Er3+ 2%@NaYF4:Nd3+ 20% nanoparticles is the highest, which is close to the emission intensity of NaYF4:Yb3+20%, Er3+ 2% nanoparticles excited by 980 nm laser. The emission intensity is enhanced by more than 600 times compared with that of NaYF4:Yb3+ 20%, Er3+ 2%, Nd3+ 20% nanoparticles. It is proved that the quench effect due to Nd incorporation is mainly related to the interaction between Nd3+ ions and the sensitizer Yb3+ ions, but not that between Nd3+ ions and the activator Er3+/Tm3+ ions. ©, 2015, Chinese Optical Society. All right reserved.