摘要
利用液相化学方法并添加有机表面活性剂合成了ZnS：Cu／ZnS核壳结构，X射线衍射表明，所合成的ZnS具有闪锌矿结构，随着ZnS包覆量的增加，核壳结构尺寸增大并在紫外-可见光谱图中的吸收峰出现红移，荧光光谱中，该纳米材料在510nm处出现荧光发射峰，主要是由于Cu2＋在t2能级上的复合跃迁。作为表面钝化层，ZnS的包覆有效地降低了晶体中Cu2＋的无辐射复合，并明显改善了znS：Cu的发光强度和发光寿命。
Via wet chemical method with organic assistant, ZnS：Cu/ZnS core/shell structure was prepared. X-ray diffraction measurements showed that ZnS：Cu was formed with zinc blende structure, and ZnS shell growth on the surface was indicated through a red-shift in the UV-Vis absorption spectra with increasing particle size. The emission peak at about 510 nm was observed, which should be assigned to recombination of an electron from the shallow delocalized donor levels at the t2 level of Cu2＋centers. As passivation layer, effect of ZnS shell on luminescence intensity and lifetime of ZnS：Cu were investigated. Comparing with uncoated ZnS：Cu, ZnS shell really enhanced the luminescence intensity and lifetime significantly, which resulted from the reduction of nonradiative recombination sites.
