Pure and Eu³⁺-doped zinc sulfide (ZnS) crystallites were synthesized through a hydrothermal method using water and ethanol (W/E) as the solvent. The powder samples have been characterized systematically using a number of characterization techniques such as X-ray diffraction, scanning electron microscopy, energy-dispersive spectroscopy, photoluminescence spectroscopy, and UV–vis absorption spectroscopy. The band gap of ZnS and ZnS/xEu³⁺ was calculated according to absorption spectroscopy, and an obvious red shift with the increasing molar fraction of Eu³⁺-doped ions was found. The luminescent mechanism of ZnS was explored by measuring the emission spectra of ZnS with different ratios of Zn and S. The emission spectra of ZnS/xEu³⁺ included the characteristic emission peak of ZnS and Eu³⁺ ions. The CIE chromaticity coordinates of the ZnS/xEu³⁺ sample varied with the molar fraction of Eu³⁺ ions. The emission intensity and morphology changed with the ratio of W/E in the process of hydrothermal reaction. The results indicate that the luminescence of the ZnS crystallite can be modulated by doping a certain amount of Eu³⁺ ions, changing the ratio of Zn and S, or adding moderate ethanol as the reaction medium.

中文翻译：

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ZnS微晶的水热合成及发光调控

以水和乙醇（W / E）为溶剂，通过水热法合成了纯的和Eu ³⁺掺杂的硫化锌（ZnS）微晶。粉末样品已使用多种表征技术进行了系统表征，例如X射线衍射，扫描电子显微镜，能量色散光谱，光致发光光谱和紫外可见吸收光谱。根据吸收光谱法计算了ZnS和ZnS / x Eu ³⁺的带隙，发现随着Eu ³⁺掺杂离子摩尔分数的增加红移明显。通过测量不同比例的ZnS的发射光谱，探索了ZnS的发光机理。x Eu ³⁺包括ZnS和Eu ³⁺离子的特征发射峰。ZnS / x Eu ³⁺样品的CIE色度坐标随Eu ³⁺离子的摩尔分数而变化。在水热反应过程中，发光强度和形貌随W / E比的变化而变化。结果表明，可以通过掺杂一定量的Eu ³⁺离子，改变Zn和S的比例或加入适度的乙醇作为反应介质来调节ZnS晶体的发光。