Preparation and Characterisation of Sr2CeO4:Eu3+ Rare Earth Luminescent Material by High Temperature Mechano-Chemical Method

A novel, high-temperature, mechano-chemical (HTMC) method was developed to synthesise single-phase Sr2CeO4:Eu3+ phosphor. Phosphors were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), and luminescence spectra. Compared with phosphors prepared by the traditional high-temperature solid state method and citric acid gel method, single-phase Sr2CeO4:Eu3+ 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 °C, and reached their maximum luminescent intensity at 900 °C. Under ultraviolet excitation at 298 nm, the sample showed good luminescence with the strongest red light of 616 nm. However, Sr2CeO4:Eu3+ was prepared at the higher temperature of 1100 °C 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 Sr2CeO4:Eu3+ phosphor at a synthesis temperature of 1100 °C by using the high-temperature solid state method, and at 1200 °C by both citric acid gel and chemical precipitation methods. Furthermore, the advantages of the Sr2CeO4:Eu3+ powder prepared by HTMC method were discussed compared with that prepared using traditional high-temperature solid state and citric acid gel methods.