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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.“,”Herein, the retention mechanisms and microstructure of Cd(Ⅱ) on MoS2 nanosheets were evaluated by batch experiments and EXAFS technology. The sorption of Cd(Ⅱ) on MoS2 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 MoS2 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 MoS2 nanosheets.