二硫化钼的水热制备及其光催化降解性能研究

发布时间：2018-04-22 00:29

  本文选题：二硫化钼 + 水热法　； 参考：《沈阳师范大学》2017年硕士论文

【摘要】：二硫化钼(MoS2)为辉钼矿的主要成分,与石墨烯具有相同的层状结构。二硫化钼纳米材料应用比较广泛,摩擦学领域、电化学领域等均有涉及。二硫化钼拥有1.78 eV的能带隙,并比表面积大,因此,在可见光催化领域具有广泛的应用前景。目前,制备二硫化钼的方法种类繁多,如利用机械剥离法制备单层二硫化钼,利用气相沉积法制备形貌各异的二硫化钼粉体,利用水热法制备不同尺寸的二硫化钼。但是,二硫化钼粉体的分散性较差,太阳光利用波段偏窄,在制氢等特定光催化领域可见光光催化效率偏低。如果制备二硫化钼过程中通过亲水性有机修饰,阻止粒子间团聚,形成可溶性二硫化钼胶体,并在表面负载光敏化剂拓展太阳光利用波段,可有效提高二硫化钼的光催化性能。本文采用二步水热法制备胶体二硫化钼,以钼酸铵和硫脲分别作为钼源和硫源,制备甲脒基硫代钼前驱体,水合肼还原前驱体,制备甲眯基二硫化钼胶体。制备过程中,利用紫外光谱和荧光光谱分析,分别考察了水热反应温度、水热反应时间、物料比对前驱体制备和二硫化钼胶体制备的影响。确定前驱体制备的最佳反应温度140℃、反应时间24 h、钼硫比1:4;还原前驱体制备二硫化钼的最佳反应温度100℃、反应时间4 h、钼氮比1:12。最后,利用三联吡啶氯化钌光敏化剂对胶体二硫化钼进行光敏化。为了考察所制备的胶体二硫化钼的光催化性能和光敏化效果,以考马斯亮蓝为光催化降解对象,进行了可见光催化降解实验。实验结果表明,三联吡啶氯化钌光敏化甲眯基二硫化钼胶体的可见光光催化效果显著。光催化效率与光敏化剂负载浓度、催化剂用量及光照强度均相关,光催化效率随着催化剂用量、光照强度及负载浓度的增加而逐渐提高,但是负载浓度过高时催化效率反而降低。
[Abstract]:Molybdenum disulfide (MoS _ 2) is the main component of molybdenum and has the same layered structure as graphene. Molybdenum disulfide nanomaterials are widely used in tribology and electrochemistry. Molybdenum disulfide has an energy band gap of 1.78 EV and a large specific surface area. Therefore, molybdenum disulfide has a wide application prospect in visible light catalysis. At present, there are many methods to prepare molybdenum disulfide, such as the preparation of monolayer molybdenum disulfide by mechanical stripping, the preparation of molybdenum disulfide powder with different morphologies by vapor deposition, and the preparation of molybdenum disulfide of different sizes by hydrothermal method. However, the dispersion of molybdenum disulfide powder is poor, the utilization band of solar light is narrow, and the visible photocatalytic efficiency is low in the specific photocatalytic field such as hydrogen production. If molybdenum disulfide was modified by hydrophilic organic modification to prevent the agglomeration between particles and form soluble molybdenum disulfide colloid, the photocatalytic activity of molybdenum disulfide could be improved effectively if the surface loaded Guang Min was used to expand the band of solar light. In this paper, the colloidal molybdenum disulfide was prepared by two-step hydrothermal method. Ammonium molybdate and thiourea were used as molybdenum source and thiourea, respectively, to prepare formamidine thio molybdenum precursor. Hydrazine hydrate was used to reduce the precursor to prepare molybdenum methylene disulfide colloid. The effects of hydrothermal reaction temperature, hydrothermal reaction time, material ratio on preparation of precursor and preparation of molybdenum disulfide colloid were investigated by UV and fluorescence spectra, respectively. The optimum reaction temperature of the precursor was 140 鈩，

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