文献类型：期刊文献

中文题名：不同pH条件下硫化钼纳米片吸附Cd(Ⅱ)的微观机制研究

英文题名：Microscopic Insights into pH-dependent Adsorption of Cd(Ⅱ) on Molybdenum Disulfide Nanosheets

作者：董丽佳[1];郭筱洁[2];李雪[1];陈朝贵[1];金阳[1];AHMED Alsaedi[3];TASAWAr Hayat[3,4];赵轻舟[5];盛国栋[6]

机构：[1]绍兴文理学院生命科学院,绍兴312000;[2]杭州电子大学材料与环境工程学院,杭州310018;[3]NAAM Research Group,Department of Mathematics,Faculty of Science,King Abdulaziz University,Jeddah 21589,Sudi Arabia;[4]Department of Mathematics,Quaid-I-Azam University,Islamabad 44000,Pakistan;[5]中国科学院大学资源与环境学院,北京100049;[6]绍兴文理学院化学与化工学院,绍兴312000

年份：2020

卷号：35

期号：3

起止页码：293

中文期刊名：无机材料学报

外文期刊名：Journal of Inorganic Materials

收录：CSTPCD、、北大核心2017、Scopus、CSCD2019_2020、北大核心、CSCD

基金：National Natural Science Foundation of China(31700476)。

语种：中文

中文关键词：硫化钼纳米片;pH;微观结构;EXAFS;Cd(Ⅱ)

外文关键词：MoS2 nanosheets;pH;microstructure;EXAFS;cadmium(Ⅱ)

中文摘要：本研究结合静态实验和X射线吸收精细结构谱学(EXAFS)评估了硫化钼纳米片对重金属Cd(Ⅱ)的吸附行为和微观机制。结果表明:Cd(Ⅱ)在硫化钼纳米片上的吸附受溶液pH、反应时间和温度的显著影响,但不受离子强度的影响。在pH 3.3~9.6范围内, pH升高显著促进了硫化钼对Cd(Ⅱ)的吸附量,但不改变吸收速率、吸附等温线和热力学。二级动力学模型能更好地拟合该吸附平衡,且内表面颗粒扩散模型显示了吸附过程中的三个典型阶段。等温线和热力学分析说明Cd(Ⅱ)在硫化钼上的吸附是异质性的、自发的、吸热的和不可逆的过程。EXAFS光谱学分析揭示了该吸附存在两种类型:在较低的pH(3.56,6.48)条件下,内表面络合以Cd–S配位键为主;在较高的pH(9.57)条件下,出现Cd(OH)2沉淀,且配位键以Cd–O和Cd–Cd的形式存在。这些研究结果对于评估重金属离子和硫化钼纳米片在分子水平上的作用机理提供了新的视野。

外文摘要：Herein, the retention mechanisms and microstructure of Cd(Ⅱ) on Mo S2 nanosheets were evaluated by batch experiments and EXAFS technology. The sorption of Cd(Ⅱ) on Mo S2 was strongly affected by solution pH, contact time, and temperature, but not by the ionic strength. The solution pH could only promote the sorption capacity, but does not improve the sorption rates and change the sorption isotherms and thermodynamics in the pH range of 3.3–9.6. The pseudo-second-order model could fit the equilibrium data better and the intra-particle diffusion model showed three typical stages in the sorption process. The isotherms and thermodynamics analysis indicated that the heterogeneity sorption of Cd(Ⅱ) onto Mo S2 was a spontaneous, endothermic, and irreversible process. The EXAFS spectra revealed the coexistence of two sorption types. The inner-sphere complexation was formed in the form of Cd–S bond at lower pH(3.56, 6.48), while the Cd(OH)2 precipitation occurred in the form of Cd–O and Cd–Cd bonds at higher pH(9.57). These results provide new insights into the interaction mechanisms between metal ions and Mo S2 nanosheets.