title: Influence of the surface structure of graphene oxide on the adsorption of aromatic organic compounds from water.
abstract: In this work, graphene oxide (GO) has been employed as an efficient adsorbent for the removal of three aromatic organic compounds (AOCs), namely, aniline, nitrobenzene, and chlorobenzene, from water under various initial AOC concentrations and pH levels. Based on the characteristics of surface structures of GO, a simple semiquantitative model has been provided to describe the intrinsic adsorption behavior of GO to AOCs. Accordingly, the adsorption mechanism has been discussed in detail at molecular levels. The contribution coefficients derived from the proposed model indicate that the most preferential interactions between GO and AOCs are hydrophobic interactions (π-π stacking and hydrophobic effect) that occur on graphitic zones of GO (unoxidized region). In the oxidized region, there also exist the hydrophobic interactions on sp(2) clusters, although they may be hindered by surrounding sp(3) zones which are the most unfavorable and are only accessible to AOCs through hydrogen bonding or electrostatic effects. More interestingly, aniline exhibits the highest contribution coefficients in both hydrophobic and hydrophilic zones of GO among the three measured AOCs due to its good water solubility and facile formation of hydrogen bonds. Furthermore, the analytical results of the adsorption isotherms are also fully consistent with those from the proposed model.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.
authors.forename: Han
authors.initials: H
authors.lastname: Yan
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.
authors.forename: Hu
authors.initials: H
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.
authors.forename: Kun
authors.initials: K
authors.lastname: Li
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.
authors.forename: Yawen
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.
authors.forename: Xue
authors.initials: X
authors.lastname: Tao
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.
authors.forename: Hu
authors.initials: H
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.
authors.forename: Aimin
authors.initials: A
authors.lastname: Li
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.
authors.forename: Rongshi
authors.initials: R
authors.lastname: Cheng
keywords: adsorption mechanism; aromatic organic compounds; graphene oxide; semiquantitative adsorption model; surface structure