Cobalt-doped zinc sulfide quantum dots with different cobalt concentrations were prepared by the solution route. Structural, optical, morphological, and magnetic responses of the prepared quantum dots were analyzed. X-ray diffraction study confirmed that cubic (zinc blende) structure is the dominant structure of synthesized samples. Crystallite size and lattice constant were found to decrease with cobalt dopant. Transmission electron microscope analysis shows that the mean size of the particles lies in the range of 7–10 nm. The absorption edge of cobalt-doped zinc sulfide nanoparticles is shifted to lower wavelength as compared to that of bulk zinc sulfide which confirmed the quantum confinement effect. The bandgap variation was observed with doping, and it varied from 4.3 to 5.6 eV. The emission spectrum reveals that the cobalt dopant suppresses the ultraviolet emission and enhances the visible emission. Fourier-transform infrared spectrum confirmed the formation of zinc sulfide and the substitution of cobalt ion. Magnetization versus magnetic field result demonstrates that the zinc sulfide and cobalt-doped zinc sulfides are superparamagnetic. Electron spin resonance spectra also confirmed the superparamagnetic nature of zinc sulfide and cobalt-doped zinc sulfide samples. Micro-Raman study also confirmed the incorporation of cobalt in the lattice and the size of the order of the exciton Bohr radius for ZnS.

通过溶液法制备了钴浓度不同的掺钴硫化锌量子点。分析了制备的量子点的结构，光学，形态和磁响应。X射线衍射研究证实立方（锌共混物）结构是合成样品的主要结构。发现微晶尺寸和晶格常数随钴掺杂剂而减小。透射电子显微镜分析表明，颗粒的平均尺寸在7-10 nm范围内。与本体的硫化锌相比，钴掺杂的硫化锌纳米粒子的吸收边缘移动到更低的波长，这证实了量子限制效应。掺杂观察到了带隙变化，其变化范围为4.3至5.6 eV。发射光谱显示钴掺杂剂抑制紫外线发射并增强可见光发射。傅里叶变换红外光谱证实了硫化锌的形成和钴离子的取代。磁化与磁场的结果表明，硫化锌和钴掺杂的硫化锌是超顺磁性的。电子自旋共振谱还证实了硫化锌和钴掺杂的硫化锌样品的超顺磁性。Micro-Raman研究还证实了钴在晶格中的结合以及ZnS的激子玻尔半径的大小。磁化与磁场的结果表明，硫化锌和钴掺杂的硫化锌是超顺磁性的。电子自旋共振谱还证实了硫化锌和钴掺杂的硫化锌样品的超顺磁性。Micro-Raman研究还证实了钴在晶格中的结合以及ZnS的激子玻尔半径的大小。磁化与磁场的结果表明，硫化锌和钴掺杂的硫化锌是超顺磁性的。电子自旋共振谱还证实了硫化锌和钴掺杂的硫化锌样品的超顺磁性。Micro-Raman研究还证实了钴在晶格中的结合以及ZnS的激子玻尔半径的大小。