用500和800℃,在氧气下,对掺Bi钨酸镉晶体进行热退火处理,测定了处理后晶体的吸收光谱与发射光谱.随退火处理温度的升高晶体的吸收强度降低,吸收边带发生蓝移.在373与980 nm的光激发下,分别观察到发光中心为528 nm的CdWO4晶体本征发光与发光中心为1078 mm的Bi5+发光.晶体样品通过高温氧气处理,发光中心为528 nm的荧光带强度增强,但发光中心为1078 nm的荧光带强度变弱.这可能是由于氧退火使Bi5+转化成Bi3+所致.经退火处理后,晶体的颜色逐渐变浅,透光率明显提高,这是由于晶体中氧空位减少所致.经γ射线辐照处理后,528 nm处的发光增强,而1078 nm处的发光减弱,这可能是由于γ射线辐照后导致Bi5+变成Bi3+.%The Bi doped tungstate of cadmium crystals were O2-annealed at various temperature, and the absorption and emission spectra of ft-annealed Bi doped tungstate of cadmium crystals were investigated. The absorption intensity decreased, and the absorption side band was shifted to blue short wavelength as the increase of annealing temperature. The emissions at 528 ran and 1 078 nm were observed under excited by 373 and 980 nm. which they were attributed to the intrinsic emission of CdWO4 crystal and emission of Bi5+ ion, respectively. After the crystals were O2-annealed, the 528 nm emission intensity enhanced while the 1 078 nm intensity reduced. It was attributed to the transformation of Bi5+ to Bi3+ ions in the annealing process. After O2 -annealed, the transmission of the crystal was enhanced obviously and the color of the crystal became weak. It is attributed to the decrease of oxygen vacancy (Vo) in crystal after the crystal was heated in O2 atmosphere. The 1 078 nm emission intensity reduced while the 528 nm intensity enhanced after the crystals were γ-irradiated. It may be due to the transormation of Bi5+ to Bi3+ ions through evolution of γ-irradiated.
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