以ZnO、S粉和六水氯化铬为原料(CrC13·6H2O),乙二胺、乙醇胺为有机溶剂,在190℃下,用溶剂热法成功地合成室温铁磁性铬掺杂ZnS纳米颗粒半导体.X-射线衍仪测试表明,Cr掺杂ZnS为纤锌矿结构.透射电镜表征不同Cr掺杂浓度ZnS的形貌为纳米颗粒,Cr掺杂浓度为5.27％的ZnS纳米颗粒平均尺寸在30～40 nm.电子能量散射谱表明产物由Zn、S、Cr元素组成.光致发光测试表明,Cr掺杂ZnS相对未掺杂ZnS吸收带边向短波方向微小移动.振动样品磁强计测试表明未掺杂的ZnS为抗磁性,而Cr掺ZnS为室温强铁磁性,Zn1-xCrxS (x=0.0527)纳米颗粒的饱和磁化强度为4.275 A/m.Cr掺ZnS纳米颗粒具有室温铁磁性的实验结果与通过第一性原理预言Cr掺ZnS纳米片具有室温铁磁性相一致.Cr掺杂ZnS纳米颗粒的铁磁性是稀磁半导体的固有属性.%Cr-doped ZnS semiconductor nanoparticles of magnetic property was successfully prepared via a solvothermal reaction of ZnO and S with CrC13 · 6H2O in mixed solvents of ethylenediamine and ethanolamine at 190 ℃.X-ray diffraction (XRD) measurement demonstrated that the undoped and Cr-doped nanoparticles had a hexagonal structure.Transmission electron microscopy (TEM) images revealed that the morphologies of ZnS with different amounts of chromium consisted of nanoparticles.The average particle size of Zn1-xCrxS (x =0.052 7) nanoparticles was in the range of 30-40 nm.This product,composed of Cr,Zn,and S,was observed by an energy dispersive spectrometer (EDS).The photoluminescence (PL) spectra of Cr doped ZnS nanoparticles showed that the absorption edge was slightly shifted towards the short wavelength compared with undoped ZnS.A vibrating sample magnetometer (VSM) showed that the Cr-doped ZnS nanoparticles exhibited increased ferromagnetism at room temperature,while the pure ZnS nanoparticles exhibited diamagnetism.The saturation magnetization of the Zn1-xCrxS (x =0.052 7) nanoparticles was 4.275 A/m.The experimental results confirmed that Cr-doped ZnS nanosheets exhibited ferromagnetism at room temperature,in good agreement with the ferromagnetic properties of Cr-doped ZnS that were predicted by first-principle computations.The origin of the ferromagnetism in the Zn1-xCrxS nanoparticles is intrinsic to the DMS.
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