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Abstract In recent years, the heavy metal ions have been immoderately released into the ecological system and result in potential hazardous to public health. Herein, the sodium dodecyl sulfate intercalated molybdenum disulfide (SDS-MoS 2) was synthesized for the adsorption of Cr(VI). The SDS molecule was flat and vertically intercalated into the interlayer of MoS 2 , which was further evidenced by density functional theory calculations. The capture of Cr(VI) on the sphere-like SDS-MoS 2 relied on solution pH. The retention of Cr(VI) on SDS-MoS 2 attained 63.92 mg/g, and the removal process was endothermic, spontaneous and increased with temperature increasing. The main removal mechanism of Cr(VI) onto SDS-MoS 2 was Cr(VI) fixing on the surface of the composites by chemisorption involving possible Cr-S coordination bonding. More importantly, Cr(VI) passed into the increased interlamination and reacted at the interlamination of SDS-MoS 2 , which was further proved at molecular level. The results can provide critical information for the application of SDS-MoS 2 in Cr(VI) elimination or other kinds of pollutants removal in natural aquatic environment. Graphical abstract Image 1 Highlights • SDS-MoS 2 was fabricated by simple hydrothermal method and applied for Cr(VI) elimination. • The adsorption of Cr(VI) on SDS-MoS 2 was pH- and ionic strength-dependent. • The adsorption of Cr(VI) on SDS-MoS 2 was chemisorption involving possible Cr-S coordination bonding. • Cr(VI) ions entered into the increased interlayer and reacted at the interlamination of SDS-MoS 2. Capsule abstract. The well-designed sphere-like SDS-MoS 2 showed high sorption of Cr(VI) through chemisorption involving Cr-S coordination bonding, and further passed into the interlamination of SDS-MoS 2 , indicating the efficient elimination of Cr(VI) from wastewater. [ABSTRACT FROM AUTHOR]

l -cysteine intercalated Mg/Al layered double hydroxide (Cys-LDH) composites were fabricated and applied for treating the U(VI) contaminated wastewater under various conditions. Interaction mechanisms and adsorption properties were investigated by using batch experiments with spectroscopy analysis. The adsorption isotherms and kinetics were fitted perfectly with the Langmuir isotherm and the pseudo-second-order model, respectively. The significant maximum adsorption capacity of Cys-LDH (211.58 mg/g) compared to LDH was attributed to the larger number of functional groups on Cys-LDH. The presence of humic acid (HA) decreased U(VI) elimination on Cys-LDH at high pH but increased U(VI) removal at low pH. Typically, the presence of various anions (such as NO 3 − , Cl − , ClO 4 − and SO 4 2− ) did not obviously affect U(VI) adsorption on Cys-LDH, while the coexisted CO 3 2− significantly affected U(VI) elimination. The predominate adsorption were determined to be the formation of Cys-U(VI)-Cys complexes with cysteine in the Cys-LDH interlayers. The results demonstrated that the Cys-LDH are promising adsorbents for efficient elimination and extraction of radionuclides in actual environmental contamination management. [ABSTRACT FROM AUTHOR]