【摘要】 采用高温固相反应合成磁铅矿型(Sr,Ba)Al12O19∶RE3+(RE=Ce,Tb)发光材料,X射线衍射结果证明生成单一磁铅矿型结构。Ce3+产生302nm的发射峰和340nm左右的不太明显的肩,分别对应于5d→2F5/2和5d→2F7/2跃迁;激发光谱显示两个宽带峰,158nm峰对应于基质吸收,260 nm峰是由4f-5d跃迁引起的。Tb3+的发射光谱显示特征的5D3→7Fj(j=2,3,4,5)和5D4→7Fj(j=4,5,6)跃迁;在激发光谱中,160nm左右的峰是由基质吸收和Tb3+-O2-电荷迁移带交迭产生的,193nm峰是Tb3+的4f-5d自旋允许跃迁引起的,233nm弱的峰是自旋禁戒4f-5d跃迁产生的。Ce3+的发射和Tb3+的f-f跃迁吸收(~320 nm)完全交迭,并且Tb3+的发光强度随Ce3+的浓度增加而增强,从激发光谱看出,Tb3+发光部分来自于Ce3+的吸收,具有Ce3+→Tb3+能量传递。更多还原

【Abstract】 The(Sr,Ba)Al12O19∶RE3+(RE=Ce,Tb) compounds have been synthesized by the solid state reaction technology.The single-phase magnetoplumbite-type crystal structure has been identified by the X-ray diffraction analysis.The 302 nm peak and ～340 nm not-clear shoulder are correspondence to the 5d→2F5/2 and 5d→2F7/2 transitions in the emission spectrum,respectively.The 158 nm peak and 260 nm peak are separately contributed to the host absorption and 4f-5d transition of Ce3+ in the excitation spectrum.The characteristic emission of 5D3→7Fj(j=2,3,4,5)and 5D4→7Fj(j=4,5,6)transitions in the range of 400-600 nm are assigned in the emission spectrum of(Sr,Ba)Al12O19∶Tb3+0.05.The ～160 nm peaks arises from the overlap of the Tb3+-O2-charge transfer band and the host absorption.The 193 nm and 233 nm peaks are attributed by the spin-allowed 4f-5d transition and the spin-forbidden transition,respectively.The overlap between the emission of Ce3+ and the f-f transition absorption of Tb3+ exists in the(Sr,Ba)Al12O19∶Tb3+,Ce3+ compounds.The luminescence intensity of Tb3+ increases with the increase of the Ce3+ ion concentration.When the Ce3+ ion concentration reaches about 0.03 mole,the luminescence intensity of Tb3+ ion is nearly two times comparing with the non-codoping Ce3+ ion compounds.When the emission wavelength is 543 nm,the excitation spectra exhibit the 4f-5d absorption of Ce3+ besides the host absorption and 4f-5d transitions of Tb3+ in the(Sr,Ba)Al12O19∶Tb3+,Ce3+ compounds.According to the excitation spectrum,the part of the emission of Tb3+ comes from the absorption of Ce3+ ion.Therefore,it is illustrated that the Ce3+→Tb3+ energy transfer has been existed in the(Sr,Ba)Al12O19∶RE3+(RE=Ce,Tb) compounds.更多还原