In this study, ultrasonic-assisted liquid-phase stripping and hydrothermal synthesis were used to prepare the two structural types of MoS₂ nanosheets, namely u-MoS₂ and h-MoS₂, respectively. The u-MoS₂ and h-MoS₂ were characterized by various techniques, and the profound relationship between the structure and preparation method was also identified. Results indicated that adsorptions of Pb^2＋ onto both u-MoS₂ and h-MoS₂ nanosheets reached equilibrium after 30 min at higher rates. The removal efficiencies of Pb^2＋ by h-MoS₂ and u-MoS₂ nanosheets were 98.4% and 20.6% under the condition of low dosage (60 mg/L). The Pb^2＋ by h-MoS₂ adsorption fitted well to the Langmuir adsorption isotherm with the adsorption capacity of 174.0 mg/g while the Pb^2＋ adsorption by u-MoS₂ fitted well to the Freundlich isotherm (n=1). The obvious discrepancy suggested that the adsorption performance was directly associated with their structural properties, which were induced by two different synthesis methods. Based on these results, the effects of operational parameters (pH, dosage and existing ions) on Pb^2＋ adsorption using h-MoS₂ were further investigated. The dosage greatly affected the adsorption capacity and removal efficiency, while pH and coexisting ions had small effects on adsorption performance. In short, this study could help to better understand the role of MoS₂ nanosheets’ structures obtained by different preparation methods for adsorption of heavy metal ions in aqueous solution.

在这项研究中，超声辅助液相剥离和水热合成被用来制备MoS ₂纳米片的两种结构类型，分别为u-MoS ₂和h-MoS ₂。用各种技术对u-MoS ₂和h-MoS ₂进行了表征，并确定了其结构与制备方法之间的深刻关系。结果表明，u-MoS ₂和h-MoS ₂纳米片上的Pb ²⁺吸附在30分钟后均以较高速率达到平衡。h-MoS ₂和u-MoS ₂去除Pb ^2＋的效率在低剂量（60 mg / L）条件下，纳米片的含量分别为98.4％和20.6％。h-MoS ₂吸附的Pb ²⁺很好地适合Langmuir吸附等温线，吸附容量为174.0 mg / g，而u-MoS ₂吸附的Pb ²⁺很好地适合Freundlich等温线（n = 1）。明显的差异表明吸附性能与其结构性质直接相关，这是由两种不同的合成方法诱导的。基于这些结果，操作参数（pH，剂量和现有离子）对使用h-MoS ₂吸附Pb ^2+的影响被进一步调查。用量极大地影响了吸附能力和去除效率，而pH和共存离子对吸附性能的影响很小。简而言之，这项研究有助于更好地了解通过不同制备方法获得的MoS ₂纳米片结构在水溶液中吸附重金属离子的作用。