Microwave-Assisted Synthesis of LaPO_4∶Ce, Tb and Phosphor Characterizations

来源 :Journal of Rare Earths | 被引量 : 0次 | 上传用户:caery
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A novel method was devised to prepare green phosphor of LaPO4∶Ce, Tb by the combination of co-precipitation and microwave irradiation. The effective hess of microwave as pre-treated process and after process and microwave irradiation time were mainly discussed. The formation process and structure of green phosphor of LaPO4∶Ce, Tb were characterized by TG-DTA, XRD and SEM, respectively. As a result, phosphor of monoclinic structure with widely distributed particle size about 70 nm was successfully synthesized. The effect of microwave-assisted method as pretreatment and after-treatment on the structure and luminescent was studied property. Results indicate that the after-treatment by microwave would enhance the crystallinity as well as fluorescence intensity, the fluorescence intensity increased with the time of microwave pretreatment time, the high fluorescence intensity was found at 80 min pretreatment time. Morphological structure of phosphor particles prepared by two methods seemed similar. The emission spectrum and excitation spectrum of phosphor as prepared detected by spectrophotometer showed typical luminescent of green phosphor, the luminescence mechanism was preliminarily discussed. A novel method was devised to prepare green phosphor of LaPO4: Ce, Tb by the combination of co-precipitation and microwave irradiation. The effective hess of microwave as pre-treated process and after process and microwave irradiation time were discussed. and a structure of green phosphor of LaPO4: Ce, Tb were characterized by TG-DTA, XRD and SEM, respectively. As a result, the phosphor of monoclinic structure with widely distributed particle size about 70 nm was successfully synthesized. The effect of microwave-assisted method as pretreatment and after-treatment on the structure and luminescent been studied property. results that the after-treatment by microwave would enhance the crystallinity as well as fluorescence intensity, the fluorescence intensity increased with the time of microwave pretreatment time, the high fluorescence intensity was found at 80 min pretreatment time. Morphological structure of phosphor particles prepared by two methods seem ed similar. The emission spectrum and excitation spectrum of phosphor as prepared detected by spectrophotometer showed typical luminescent of green phosphor, the luminescence mechanism was preliminarily discussed.
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