Cu掺杂无水芒硝的光致发光特性

Luminescence Properties of Thenardite Activated with Cu

在气温1 100℃下,将纯天然无水芒硝(Na2SO4)和Cu的混合粉末加热20 min,制备了Na2SO4∶Cu发光材料。在室温中测量了光致发光谱。通过实验结果发现发射光谱形状依赖于激发波长,在260 nm激发下的发射光谱是由峰值位于430 nm处的宽带谱构成,所得到的宽带谱归属于Cu+内电子的3d94s→3d10跃迁。在300 nm激发下的发射光谱分别由峰值在430和550 nm处的两个宽带谱组成,分别归属于Cu+内3d94s→3d10跃迁和Na2SO4的导带至Na2SO4带隙中Cu2+激发态Cu2+(d9)的跃迁。随着Cu掺杂量的增加,在430 nm处的发光不产生浓度猝灭,而550 nm处产生了明显的浓度猝灭。

Na2SO4∶Cu phosphors were prepared by heating pure natural thenardite with Cu at 1 100 ℃ for 20 min in air.Their photoluminescence spectra were investigated at room temperature.The shapes of emission spectra depend on the excitation wavelengths,The emission spectrum under 260 nm excitation consists of a broad band with a peak at 430 nm,which can be attributed to the 3d 94s→3d10 transition within Cu＋.The emission spectrum under 300 nm excitation consists of two broad bands with peaks at 430 and 550 nm respectively,which can be attributed to the 3d 94s→3d10 transition within Cu＋ and transition from the conduction band of Na2SO4 to the level of excited Cu2＋（d9） in the Na2SO4 band gap,respectively.With the increase in Cu contents,concentration quenching did not occur in the luminescence at 430 nm,but occured at 550 nm.