Co掺杂ZnS量子点荧光探针检测水体中Pb2+和Cu2+

Co-doped ZnS quantum dots as fluorescent probe in the determination of Pb2+ and Cu2+ in tap water

中文关键词:  ZnS:Co量子点  L-半胱氨酸  表面修饰  荧光检测  Pb2+  Cu2+

英文关键词:ZnS:Co quantum dots  L-cysteine  surface modification  fluorescence detection  Pb2+  Cu2+

中文摘要:

      目的 以L-半胱氨酸作为表面修饰剂, 采用水热法合成掺杂Co的ZnS量子点(ZnS:Co), 并通过此量子点构建对Pb2+和Cu2+的荧光检测探针。方法 通过X射线衍射(X-ray diffraction, XRD)、透射电子显微镜(transmission electron microscope, TEM)、X射线光电子能谱(X-ray photoelectron spectroscopy, XPS)和光致发光光谱(photoluminescence spectroscopy, PL)对样品进行表征和分析。结果 ZnS:Co量子点为立方闪锌矿结构, 颗粒呈不规则球形, 平均粒径约为4.51 nm。ZnS:Co量子点相较纯ZnS量子点荧光强度增强了近4倍。基于ZnS:Co量子点构建了对Pb2+和Cu2+的荧光检测。Pb2+和Cu2+的加入会引起ZnS:Co量子点的荧光淬灭, ZnS:Co量子点只对Pb2+和Cu2+离子表现出良好的荧光响应, 并且表现出良好的抗干扰能力。结论 ZnS:Co量子点可以实现对水体中Pb2+和Cu2+的荧光检测。

英文摘要:

      Objective Using L-cysteine as a surface modifier, to synthesize Co-doped ZnS quantum dots (ZnS:Co) by a hydrothermal method, and construct fluorescence detection probes for Pb2+ and Cu2+ by the quantum dots. Methods The samples was characterized and analyzed by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and photoluminescence spectroscopy (PL). Results ZnS:Co quantum dots had a cubic sphalerite structure with irregular spherical particles and the average particle size of about 4.51 nm. Compared with pure ZnS quantum dots, the fluorescence intensity of ZnS:Co quantum dots was nearly 4 times stronger. Based on ZnS:Co quantum dots, the fluorescence detection of Pb2+ and Cu2+ was constructed. The addition of Pb2+ and Cu2+ could cause the fluorescence quenching of ZnS:Co quantum dots. ZnS:Co quantum dots only showed good fluorescence response to Pb2+ and Cu2+ ions, and showed good interference immunity. Conclusion ZnS:Co quantum dots can achieve fluorescence detection of Pb2+ and Cu2+ in water.