Investigation on charging processes and phosphorescent efficiency of SrAl2O4:Eu,Dy

RETRACTED: Luminescence enhancement of bluish-green Sr2Al2SiO7:Eu2+ phosphor by dysprosium co-doping

“…Equation (8) shows that impact time remains mostly unchanged with increasing impact velocity because there is no significant change in compression, which is expressed by 'x' in equation (8). This may be one possible reason why the time that corresponds to the peak ML intensity does not change significantly with increasing impact velocity [56].…”

Temperature dependence of persistent luminescence in β-irradiated SrAl2O4:Eu2+, Dy3+ phosphor

“…These trapping defects have been ascribed to oxygen vacancies levels [7][8][9] and to rare-earth Ln 3+ cations, which might be reduced into their Ln 2+ state with 4f n+1 configuration lying just below the conduction band [10]. In the present case based on the TL experiments performed in beta-irradiated SrAl 2 O 4 :Eu 2+ , Dy 3+ phosphor in which the trap depths of the low-temperature glow peaks are less than 1 eV [20,21,24] and close to the ground state of Dy 2+ located 0.9 eV below the bottom of the CB, we may assume that the traps responsible for the TL glow peak components in the SrAl 2 O 4 :Eu 2+ , Dy 3+ phosphor are due to the Dy 2+ ions (intermediate trapping levels) although we have no basis to rule out the participation of oxygen vacancies trapping levels. The trapped electrons at the intermediate trapping levels may transfer from one trap to another (electron hopping) and eventually will return to the 5d level of Eu 3+ cations.…”

Investigation on the improvement of red phosphorescence in CaTiO3:Pr3+ nanoparticles

“…4. The areas (S 1 for the nano-samples and S 0 1 for the bulk) above the charging curve and below the dashed lines represent the energy stored in the traps [10]. It is found that S 1 is much greater than S 0 1 , indicating more energy stored in nanophosphors than that in the bulk, although the fluorescence in nanophosphors is weaker than that of the bulk.…”