title: Sorption mechanisms of perfluorinated compounds on carbon nanotubes.
abstract: Sorption of perfluorinated compounds (PFCs) on carbon nanotubes (CNTs) is critical for understanding their subsequent transport and fate in aqueous environments, but the sorption mechanisms remain largely unknown. In this study, the sorption of six PFCs on CNTs increased with increasing C-F chain length when they had a same functional group, and the CNTs with hydroxyl and carboxyl groups had much lower adsorbed amount than the pristine CNTs, indicating that hydrophobic interaction dominated the sorption of PFCs on the CNTs. Electrostatic repulsion suppressed the sorption of PFCs on the CNTs, resulting in the lower sorption with increasing pH. Hydrogen bonding interaction was negligible. The hydrophobic C-F chains can be closely adsorbed on the CNTs surface in parallel to the axis or along the curvature, making it impossible to form micelles on the CNT surface, leading to the lower sorption than other adsorbents.
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, POPs Research Center, Tsinghua University, Beijing 100084, China. dengshubo@tsinghua.edu.cn
authors.forename: Shubo
authors.initials: S
authors.lastname: Deng
authors.forename: Qiaoying
authors.initials: Q
authors.lastname: Zhang
authors.forename: Yao
authors.initials: Y
authors.lastname: Nie
authors.forename: Haoran
authors.initials: H
authors.lastname: Wei
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Huang
authors.forename: Gang
authors.initials: G
authors.lastname: Yu
authors.forename: Baoshan
authors.initials: B
authors.lastname: Xing
mesh_terms: D000327:Adsorption; D052918:Environmental Restoration and Remediation / Q000379:methods; D005466:Fluorocarbons / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D008956:Models, Chemical; D037742:Nanotubes, Carbon / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D005466:Fluorocarbons; D037742:Nanotubes, Carbon; D014874:Water Pollutants, Chemical