【摘要】 采用高温固相法制备了一系列样品Y2.95-xDyxAl5O12∶Ce03.+05(x=0,0.59,1.18,1.77,2.36,2.95)。用X射线粉末衍射法测量了Y3Al5O12∶Ce3+组成中Dy3+替代Y3+所造成的晶格膨胀,结果表明晶格膨胀与Dy3+替代量(x值)之间成线性关系。对样品的发射光谱分析表明Dy3+替代Y3+会造成发射峰的红移,且发射峰红移与x值之间成线性关系。全部样品在紫外光激发后均具有黄色长余辉,余辉时间随着x值的增加而减小。热释光谱测试表明样品中存在两种不同深度的陷阱能级,Dy3+的替代并不增加基质中的陷阱能级种类,但是可以降低基质中的陷阱能级深度,有利于常温下陷俘于陷阱中的电子的逃逸。更多还原

【Abstract】 A series of samples with the composition Y2.95-xDyxAl5O12∶Ce3+0.05(x=0,0.59,1.18,1.77,2.36,2.95) are prepared by high-temperature solid-phase method.The structure of samples is studied by X-ray powder diffraction method.The results show that crystal lattice of the host expands when Y3+ is substituted by Dy3+,and the expansion is proportional to the amount of Dy3+ which substitutes Y3+.The photoluminescence analysis shows that the substitution results in red shift of emitting peak position and the red shift is also proportional to the value of x.All the samples show yellow long afterglow after they are excited by ultraviolet light.The afterglow time decreases with the value of x.The thermoluminescence analysis shows that there are two kinds of traps with different depths in the host crystal lattice.The substitution of Dy3+ does not change the sorts of traps but it is able to lower the energy level of the traps which is advantageous to the release of electrons in the traps at room temperature.更多还原