A novel, high-temperature, mechano-chemical（HTMC） method was developed to synthesise singlephase Sr_2CeO_4：Eu^（3＋）phosphor. Phosphors were characterised by X-ray diffraction（XRD）, scanning electron microscopy...A novel, high-temperature, mechano-chemical（HTMC） method was developed to synthesise singlephase Sr_2CeO_4：Eu^（3＋）phosphor. Phosphors were characterised by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, and luminescence spectra. Compared with phosphors prepared by the traditional hightemperature solid state method and citric acid gel method, single-phase Sr_2CeO_4：Eu^（3＋）powders by using the HTMC method, with small average particle sizes of about 5 μm, a narrow size distribution range and uniform dispersion, were prepared at 800 ℃, and reached their maximum luminescent intensity at 900 ℃.Under ultraviolet excitation at 298 nm, the sample showed good luminescence with the strongest red light of 616 nm. However, Sr_2CeO_4：Eu^（3＋）was prepared at the higher temperature of 1100 ℃ by solid state method and citric acid gel method. The particle size was too large and uneven with phosphor agglomeration by high-temperature solid state method. The luminescent intensity reached a maximum for Sr_2CeO_4：Eu^（3＋）phosphor at a synthesis temperature of 1100 ℃ by using the high-temperature solid state method, and at 1200 ℃ by both citric acid gel and chemical precipitation methods. Furthermore, the advantages of the Sr_2CeO_4：Eu^（3＋）powder prepared by HTMC method were discussed compared with that prepared using traditional high-temperature solid state and citric acid gel methods.展开更多
文摘A novel, high-temperature, mechano-chemical（HTMC） method was developed to synthesise singlephase Sr_2CeO_4：Eu^（3＋）phosphor. Phosphors were characterised by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, and luminescence spectra. Compared with phosphors prepared by the traditional hightemperature solid state method and citric acid gel method, single-phase Sr_2CeO_4：Eu^（3＋）powders by using the HTMC method, with small average particle sizes of about 5 μm, a narrow size distribution range and uniform dispersion, were prepared at 800 ℃, and reached their maximum luminescent intensity at 900 ℃.Under ultraviolet excitation at 298 nm, the sample showed good luminescence with the strongest red light of 616 nm. However, Sr_2CeO_4：Eu^（3＋）was prepared at the higher temperature of 1100 ℃ by solid state method and citric acid gel method. The particle size was too large and uneven with phosphor agglomeration by high-temperature solid state method. The luminescent intensity reached a maximum for Sr_2CeO_4：Eu^（3＋）phosphor at a synthesis temperature of 1100 ℃ by using the high-temperature solid state method, and at 1200 ℃ by both citric acid gel and chemical precipitation methods. Furthermore, the advantages of the Sr_2CeO_4：Eu^（3＋）powder prepared by HTMC method were discussed compared with that prepared using traditional high-temperature solid state and citric acid gel methods.
