The SrAl 2O 4∶Eu 2+ , Nd 3+ and SrAl 2O 4∶Eu 2+ , Dy 3+ long afterglow phosphor were synthesized. Their excitation and emission spectra at different excitation and afterglow characteristics wer...The SrAl 2O 4∶Eu 2+ , Nd 3+ and SrAl 2O 4∶Eu 2+ , Dy 3+ long afterglow phosphor were synthesized. Their excitation and emission spectra at different excitation and afterglow characteristics were analyzed after the excitation power was taken off. The effects of Eu 2+ , Dy 3+ , Nd 3+ mole concentrations on phosphorescence characteristics were also discussed. It is crucial to have trapping levels located at a suitable depth related to the thermal release rate at room temperature. The incorporation of Nd 3+ ions as an auxiliary activator into the SrAl 2O 4∶Eu 2+ system causes very intense and long phosphorescence. The response time of SrAl 2O 4∶Eu 2+ , Dy 3+ phosphors is quicker than that of SrAl 2O 4∶Eu 2+ , Nd 3+ . Phosphorescence characteristics of SrAl 2O 4∶Eu 2+, Nd 3+ is much better than those of SrAl 2O 4∶Eu 2+ , Dy 3+ . The integrate area of the excitation spectrum of SrAl 2O 4∶Eu 2+ , Nd 3+ phosphor is larger than that of SrAl 2O 4∶Eu 2+ , Dy 3+ phosphor within the range of 250～360 nm. For phosphorescence characteristics to the system of SrAl 2O 4∶Eu 2+ , Nd 3+ phosphor, the optimum concentration of Nd 3+ trivalent rare earth ions is 0.05 mol.展开更多
New long phosphorescent phosphors Ba 1-xCa xAl 2O 4∶Eu 2+, Dy 3+ with tunable color emission were prepared and studied. The emission spectra show that the tuning range of the color emission of the phosphors i...New long phosphorescent phosphors Ba 1-xCa xAl 2O 4∶Eu 2+, Dy 3+ with tunable color emission were prepared and studied. The emission spectra show that the tuning range of the color emission of the phosphors is between 498 and 440 nm, which is dependent on x, under the excitation of UV. The wavelength of the afterglow increases with the increasing of x until x equals 0.6. The XRD patterns show that the single phase limit in the phosphors is below x value of 0 4. The Thermoluminescence spectra were measured to investigate the traps created by the doping of Dy 3+.展开更多
Long-lasting SrAl2O4∶Eu, Dy phosphor was successfully prepared from a mesoporous precursor. The precursor was synthesized by templating method using nonionic Polyethylene Oxide (PEO) as surfactants, which was proved ...Long-lasting SrAl2O4∶Eu, Dy phosphor was successfully prepared from a mesoporous precursor. The precursor was synthesized by templating method using nonionic Polyethylene Oxide (PEO) as surfactants, which was proved by TG-DTG, X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) analysis. The analysis results indicated that regular cylindrical-to-hexagonal shaped pores with several nanometers were obtained. The structure and morphology of the SrAl2O4∶Eu, Dy phosphor by templating method was characterized by XRD and Scanning Electron Microscopy (SEM). The XRD results showed that a pure SrAl2O4 phase formed at 900 ℃ by templating method. The SEM morphologies of the obtained phosphors prepared by templating synthesis were uniform and porous multicrystalline with average diameter size of 5 μm. The broad-band UV-excited SrAl2O4∶Eu, Dy phosphor derived from a mosoporous precursor was observed at λmax=515 nm due to the transitions from the 4f65d1 to the 4f7 configurations of Eu2+ ion. The main excitation and emission intensity of the phosphor with this method were stronger than that obtained by solid state reaction method. And the obtained long-lasting phosphor with this method revealed a better afterglow compared to the phosphor prepared through solid state reaction method.展开更多
文摘The SrAl 2O 4∶Eu 2+ , Nd 3+ and SrAl 2O 4∶Eu 2+ , Dy 3+ long afterglow phosphor were synthesized. Their excitation and emission spectra at different excitation and afterglow characteristics were analyzed after the excitation power was taken off. The effects of Eu 2+ , Dy 3+ , Nd 3+ mole concentrations on phosphorescence characteristics were also discussed. It is crucial to have trapping levels located at a suitable depth related to the thermal release rate at room temperature. The incorporation of Nd 3+ ions as an auxiliary activator into the SrAl 2O 4∶Eu 2+ system causes very intense and long phosphorescence. The response time of SrAl 2O 4∶Eu 2+ , Dy 3+ phosphors is quicker than that of SrAl 2O 4∶Eu 2+ , Nd 3+ . Phosphorescence characteristics of SrAl 2O 4∶Eu 2+, Nd 3+ is much better than those of SrAl 2O 4∶Eu 2+ , Dy 3+ . The integrate area of the excitation spectrum of SrAl 2O 4∶Eu 2+ , Nd 3+ phosphor is larger than that of SrAl 2O 4∶Eu 2+ , Dy 3+ phosphor within the range of 250～360 nm. For phosphorescence characteristics to the system of SrAl 2O 4∶Eu 2+ , Nd 3+ phosphor, the optimum concentration of Nd 3+ trivalent rare earth ions is 0.05 mol.
文摘New long phosphorescent phosphors Ba 1-xCa xAl 2O 4∶Eu 2+, Dy 3+ with tunable color emission were prepared and studied. The emission spectra show that the tuning range of the color emission of the phosphors is between 498 and 440 nm, which is dependent on x, under the excitation of UV. The wavelength of the afterglow increases with the increasing of x until x equals 0.6. The XRD patterns show that the single phase limit in the phosphors is below x value of 0 4. The Thermoluminescence spectra were measured to investigate the traps created by the doping of Dy 3+.
基金the National Natural Science Foundation of China (20376009)
文摘Long-lasting SrAl2O4∶Eu, Dy phosphor was successfully prepared from a mesoporous precursor. The precursor was synthesized by templating method using nonionic Polyethylene Oxide (PEO) as surfactants, which was proved by TG-DTG, X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) analysis. The analysis results indicated that regular cylindrical-to-hexagonal shaped pores with several nanometers were obtained. The structure and morphology of the SrAl2O4∶Eu, Dy phosphor by templating method was characterized by XRD and Scanning Electron Microscopy (SEM). The XRD results showed that a pure SrAl2O4 phase formed at 900 ℃ by templating method. The SEM morphologies of the obtained phosphors prepared by templating synthesis were uniform and porous multicrystalline with average diameter size of 5 μm. The broad-band UV-excited SrAl2O4∶Eu, Dy phosphor derived from a mosoporous precursor was observed at λmax=515 nm due to the transitions from the 4f65d1 to the 4f7 configurations of Eu2+ ion. The main excitation and emission intensity of the phosphor with this method were stronger than that obtained by solid state reaction method. And the obtained long-lasting phosphor with this method revealed a better afterglow compared to the phosphor prepared through solid state reaction method.
