摘要
本文在室温下研究了BaMgF_4氟化物中Gd^(3+)和Tb^(3+)离子的荧光光谱以及它们之间的能量传递。在BaMgF_4中Gd^(3+)可以直接将激发能传递给Tb^(3+)离子:在Tb^(3+)(4f^75d)-Gd^(3+)(4f)-Tb^(3+)(4f^8)能量输运过程中,Gd^(3+)离子可起中间体作用。
Trivalent gadolinium is an important activator and sensitizer.In the present paper, the investigation at room temperature on spectra of Gd + ion and energy transfer between Gd3+ and Tb3+ in the systems of BaMgF4:Gd3+ and BaMgF4:Gd3+ Tb3+ are reported. Samples studied were prepared by a solid-state at high temperature from BaF2 ,MgF2 ,GdF3 and TbF3 under a flow of hydrogen-nitrogen mixture.Compositions of BaMgF4 :xGd show the Gd3+ characteristic narrow emission at 311nm under the excitation of short-wave-length ultraviolet radiation (see Fig.2). The excitation spectrum of the Gd3+ 311nm emission consists of the 8S7/2-6I7 and -6D7 transitions. The Gd3+ emission intensity depends on Gd3+ concentration (Fig.3).The emission intensity of the Tb3+ 5D4-7FJ transition is considerably enhanced in BaMgF4:Tb3+ by codoping with Gd3+ ions.The excitation spectra of Tb3+ emission for BaMgF4:Gd,Tb are shown in Fig.5 and 6, have the following features:(1) the excitation lines (272 and 311nm) corresponding to Gd3+ transitions of 8S7/2-6P7/2 and -6IJ levels are presented in the excitation spectrum of Tb3+ emission;(2) the excitation of Tb3+ 544nm emission which lies in the region of short-wave length UV from 220 to 265nm are heavily enhanced;(3) the Tb3+ excitation spectrum at near UV region (330 to 385nm) is also enhanced. The near-UV optical region is below the lowest excited 6P7/2 level of Gd3+ ion;(4) the emission intensity of Tb3+ ion depends considerably upon the Gd3+ concentration. Energy transfer between Gd3+ and Tb3+ ions in barium magnesium complex fluorides is discussed.
出处
《发光学报》
EI
CAS
CSCD
北大核心
1990年第4期277-285,共9页
Chinese Journal of Luminescence
基金
国家自然科学基金资助课题
