Comparative adsorption of heavy metal ions in wastewater on monolayer molybdenum disulfide

• DOI: 10.1016/j.gee.2020.06.019
• Publication Date: 2020-06-30T06:41:19Z
• Authors: Zheng Zhang; Kai Chen; Qiang Zhao; Mei Huang; Xiaoping Ouyang
• Keywords: First-principles calculation; Ecology; TJ807-830; Wastewater; 01 natural sciences; Renewable energy sources; 6. Clean water; Monolayer MoS2; 0104 chemical sciences; Heavy metal ions; Adsorption; QH540-549.5

To maximize the potential of monolayer molybdenum disulfide (MoS2) sheet in the disposal of heavy metal ions in wastewater, we compared the adsorption of several common heavy metal ions (including Cr3+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, and Pb2+) in wastewater on the monolayer MoS2 sheet through first-principles calculation. Our simulation results show that the monolayer MoS2 sheet is a potential heavy metal adsorption material because of the attractive interaction between them. The most negative adsorption energy determines that the TMo site is the most stable adsorption site for the heavy metal ions. The attractive interaction is considered as chemical adsorption, and it is closely related to charge transfer. The orbital hybridization between S p and heavy metal ions p and d states electrons contributes to the adsorption, except the orbital hybridization between S p and Pb p states electrons contributes to the Pb2+ adsorption. All the results show that the monolayer MoS2 sheet is most suitable for removing Ni2+ and Cr3+ ions from wastewater, followed by Cu2+ and Pb2+. For the ions Cd2+, Zn2+, and Hg2+, its adsorption strength remains to be improved.