沉淀法制备ZnS∶Cr纳米晶及其光学性能研究

以十二烷基苯磺酸钠和六偏磷酸钠作为分散剂,采用沉淀法制备了ZnS及不同掺杂浓度的ZnS∶Cr纳米晶。利用XRD和TEM对纳米晶物相和形貌进行了分析。结果表明,ZnS和ZnS∶Cr纳米晶均为立方闪锌矿结构,利用谢乐公式估算ZnS和ZnS∶Cr纳米晶平均粒径分别为2.1和2.2nm。TEM观察到纳米晶近似为球形,平均粒度为3nm左右,具有较好的单分散性且分布均匀。荧光光谱(PL)表明,纳米晶在420、440和495nm处有发射谱带,前两者被认为是S空位深陷阱发光,后者被认为是表面态或中心辐射复合发光。

Synthesis and characterization of ZnS:Cr nanocrystals by co-precipitation

ZnS and ZnS:Cr nanocrystals were synthesized by chemical co-precipitation method.Sodium lauryl benzenesulfate and sodium-hexametaphosphate were used as a dispersant.The crystalline,microscopy and luminescent properties of ZnS:Cr nanocrystals were characterized by X-ray diffraction (XRD),transmission electron microscopy (TEM) and photoluminescence (PL) spectra.The results show that ZnS:Cr nanocrystals have cubic zinc blende crystal structure,and the size of these spheroidal particles is about 3nm.At room temperature,the luminescence properties are investigated with PL spectra.In PL spectra,the emission peaks of ZnS:Cr at about 420 and 440nm,which may be attributed to sulfur vacancy.The emission peak at 495nm of ZnS:Cr be assigned to the emitting of surface states or centers of radiation.Fourier transform infrared red (FT-IR) spectroscopy results provide evidence of the presence of sodium-hexametaphosphate and TAA.