Luminescent properties and quenching effects of Pr3+ co-doping in SiO2:Tb3+/Eu3+ nanophosphors

• CL and PL properties of singly doped SiO2:Pr3+.
• Quenching effects by Pr3+ ions in both SiO2:Eu3+, Pr3+ and SiO2:Tb3+, Pr3+ phosphors.
• Quenching mechanisms hindering interaction between Pr3+–Eu3+ and Pr3+–Tb3+ ion pairs are also discussed.
• Difference on the PL and CL spectra from both single and Pr3+ co-doped SiO2:Eu3+/Tb3+ phosphors.

Luminescence properties of Pr3+ single doped SiO2 and Pr3+ co-doped SiO2:Tb3+/Eu3+ nanophosphors synthesized using sol–gel method were investigated. X-ray diffraction (XRD), and scanning electron microscope (SEM) were used to study the phase structure and particle morphology, respectively. The photoluminescence (PL) and cathodoluminescence (CL) properties of SiO2:Pr3+ and Pr3+ co-doped SiO2:Tb3+/Eu3+ were investigated. The concentration quenching effects at high concentrations of Pr3+ were observed from both PL and CL data. The PL and CL intensities from SiO2:Eu3+/Tb3+ nanophosphors were shown to decrease significantly with Pr3+ co-doping and the possible causes for the decrease are discussed Fluorescence lifetimes of the 1D2 emitting level of Pr3+ were determined from luminescence decay curves of SiO2:Pr3+ at different Pr3+ concentrations.