ZnS:Cu纳米颗粒的制备及发光性质  

Preparation and luminescence properties of ZnS:Cu nanocrystals

作　　者：孙远光[1] 曹立新[1] 柳伟[1] 苏革[1] 曲华[1] 姜代旬[1] 

机构地区：[1]中国海洋大学材料科学与工程研究院,山东青岛266100

出　　处：《功能材料》2009年第4期689-692,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(50672089);山东省优秀中青年科学家奖励基金资助项目(2006BS04034)

摘　　要：采用水热法制备了Cu离子掺杂的ZnS（ZnS：Cu）纳米颗粒，研究了锌硫比和反应时间对ZnS：Cu纳米颗粒光致发光性质的影响。通过X射线衍射（XRD）和透射电子显微镜（TEM）对样品的物相和形貌进行分析表征，发现该方法得到立方闪锌矿结构的球形ZnS：Cu纳米晶，粒径在1～6nm之间。室温下，用350nm波长的紫外光激发ZnS：Cu纳米粒子，可以得到归属于浅施主能级与铜t2能级之间的跃迁产生的绿色发光，发光强度随锌硫比的增大和反应时间的延长先增强后减弱，发射峰位随锌硫比和反应时间的变化有一定移动。认为浅施主能级为与硫空位有关的能级，锌硫比和反应时间对硫空位的数量和能级位置有一定影响。ZnS is a wide direct band gap of Ⅱ-Ⅵ compound,which is a widely used matrix in various luminescent materials. ZnS materials doped with different rare metal ions and transition metal ions （Mn,Cu,Ag） formed by different techniques have been studied widely in recent years. Compared to other ions-doped ZnS,Cu-doped ZnS is rarely studied by researchers, especially as photoluminescence nanoparticles. This paper introduces a method of hydrothermal used to prepare ZnS ： Cu nanocrystals. And on this base,the effections of reaction time and the mole ratio of zinc and sulfur on the luminescence properties of ZnS ： Cu nanocrystals are investigated. X-ray diffractometer and transmission electron microscope are used to characterize the phase and the surface morphology of samples. The results show that ZnS ： Cu nanocrystals have cubic zinc blende crystal structure,and the size of these spheroidal particles is in a range of 1 to 6nm. At room temperature, the luminescence properties are investigated with PL spectra and PLE spectra. In PL spectra, emission peaks are at about 542nm, which may be attributed to a transition from shallow donor state of ZnS to the t2 level of Cu in ZnS band gap. In PLE spectra,excitation peaks are at about 350nm, which are attributed to the near-band-edge absorption of ZnS matrix. Luminescence intensity increases, and then decreases with the mole ratio of zinc and sulfur increasing. When the mole ratio of Zinc and Sulfur is 2 ： 1, luminescence intensity touches its maximum. When excitation wavelength is 350nm, ZnS ： Cu nanocrystals give off green band emissions from 510-542nm,according to the extend of reaction time. And the highest intensity appears in the sample which has reacted for 8h. Following this method,ZnS ： Cu nanocrystals giving green luminescence can be prepared. It can be deduced that shallow donor state of ZnS ： Cu nanocrystals is concerned with sulfur vacancies. The numbers and the levels of sulfur vacancies are affected by the reaction time and the mole ratio of Zi

关 键 词：ZnS:Cu纳米晶 水热法 光致发光 

分 类 号：O611.4[理学—无机化学] O614.24[理学—化学]