title: Aqueous stability and mobility of C₆₀ complexed by sodium dodecyl benzene sulfonate surfactant.
abstract: Surfactant complexation may have significant effects on the environmental behavior of nano-particles. In order to understand the ecological exposure of nano-materials, it is important to determine the stability and mobility of surfactant-complexed nano-materials in aqueous systems. In this study, the aggregation and transport of C60 complexed by the surfactant sodium dodecyl benzene sulfonate (SDBS) were investigated. It was found that SDBS-complexed C60 had a ζ-potential of -49.5 mV under near-neutral pH conditions and remained stable during an aging period of 15 days. It had a critical coagulation concentration of 550 mmol/L for NaCl, which was higher than common natural colloids and many kinds of raw nano-materials, and was comparable to those of many kinds of surface-modified nano-materials. SDBS enhanced the stability of C60 colloid; however, at the same time, it also enhanced the colloidal particle aggregation rate. Much higher mobility was found for SDBS-complexed C60 than C60 colloid. Increase in ionic strength, Ca(2+) concentration or Al(3+) concentration decreased the mobility. In general, SDBS-complexed C60 had high stability and mobility.
authors.affiliation: Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: xjpeng@rcees.ac.cn.
authors.forename: Xianjia
authors.initials: X
authors.lastname: Peng
authors.affiliation: Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Liang
mesh_terms: D001557:Benzenesulfonates / Q000737:chemistry*; D003102:Colloids / Q000737:chemistry; D037741:Fullerenes / Q000032:analysis / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008956:Models, Chemical; D009994:Osmolar Concentration; D012965:Sodium Chloride; D013501:Surface-Active Agents / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
chemical_list: D001557:Benzenesulfonates; D003102:Colloids; D037741:Fullerenes; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical; D012965:Sodium Chloride; C001114:dodecylbenzenesulfonic acid; C069837:fullerene C60
keywords: Aggregation; Carbon nano-materials; Fullerene; Surfactant; Transport