由高温固相反应制得Ba0.955Al2Si2-xTixO8∶Eu2+(x=0~1.0)系列试样,通过XRD和荧光光谱测试,研究各试样的晶体结构和光谱特性。XRD分析结果表明,当Ti4+置换Si4+的量逐渐增至1.0时,各试样均为单斜晶系,空间群为C2/m(12),其晶胞参数a,b,c,β和晶胞体积V呈线性递增,其中晶胞参数c变化幅度最大,a最小,试样的晶粒尺寸略微减小。荧光光谱分析结果表明,试样的荧光激发谱为宽带,位于230~400 nm,可264 nm、303 nm、341nm和367 nm四个峰拟合成,表观峰值位于340 nm;试样的发射光谱为370~600 nm一宽带不对称峰,峰值为434nm,可拟合成419 nm和453 nm两峰,两拟合峰峰位随Ti4+置换量增加线性红移;利用试样荧光光谱和Van Uitert经验公式,得出Ba Al2Si2O8∶Eu2+中Ba2+的配位数为9。
A series of phosphors Ba0. 955Al2Si2- xTixO8∶ Eu2 +( x = 0-1. 0) were prepared via solid-state reaction. The crystal structure and the luminescent properties of the samples were measured and characterized by using the method of XRD and fluorescence spectrum. The analysis results of XRD show that the samples are monoclinic and the space group is C2 / m( 12) in the whole range for x = 0-1. 0 while Ti4 +enterers Ba Al2Si2O8 lattice and substitutes for Si4 +. The lattice parameters( a,b,c,β) and unit cell volume of phosphors Ba0. 955Al2Si2- xTixO8∶ Eu2 +( x = 0-1. 0) increase linearly as Ti4 +content increases in the phosphors. When Ti4 +substitutes for Si4 +the most obvious change is in cell parameter c,the minimum is a,The grain size of samples decreases slightly. The analysis results of fluorescence spectrum show that a broad excitation spectrum of Eu2 +is shown from 230-400 nm and the apparent peaked 340 nm,which can be deconvoluted to 264 nm,303 nm,341 nm and 367 nm excitation bands.The broad and asymmetric emission spectrum among 370 nm and 600 nm and apparent peak is at 434 nm,which can be deconvoluted to two peaks of 419 nm and 453 nm. The two peaks are red shifted with the increase of the amount of Ti4 +substitution. The coordination number of Ba2 +is 9 in Ba Al2Si2O8∶ Eu2 +,which has been confirmed by the experimental results and empirical formula of Van Uitert.