title: Facile hydrothermal preparation of recyclable S-doped graphene sponge for Cu2+ adsorption.
abstract: Graphene sponge (GS) has been widely employed for water purification, but adsorption capacity loss frequently occurs during the formation of spongy structure. In this study, we reported the hydrothermal preparation of S-doped GS for the removal of Cu(2+) with a huge adsorption capacity of 228 mg/g, 40 times higher than that of active carbon. The adsorption isotherm could be well fitted into the Freundlich model with a KF value of 36.309(L/mg)(1/n). The equilibrium adsorption could be fully achieved in the first 5 min. In the thermodynamics study, the negative ΔG indicated that the adsorption was spontaneous and physisorption in nature. The positive ΔH implied that the adsorption was endothermic. The changes of both pH and ionic strength had no apparent influence on the adsorption. S-doped GS could be easily regenerated by washing with acidic thiourea. Moreover, S-doped GS could be used for the adsorption of other heavy metal ions, too. The implication to the applications of S-doped GS in water treatment is discussed.
authors.affiliation: College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China.
authors.forename: Lianqin
authors.initials: L
authors.lastname: Zhao
authors.affiliation: College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China.
authors.forename: Baowei
authors.initials: B
authors.lastname: Yu
authors.affiliation: Shandong Provincial Analysis and Tester Center, Shandong Academy of Science, Jinan 250014, PR China.
authors.forename: Fumin
authors.initials: F
authors.lastname: Xue
authors.affiliation: College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China.
authors.forename: Jingru
authors.initials: J
authors.lastname: Xie
authors.affiliation: College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China.
authors.forename: Xiaoliang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China.
authors.forename: Ruihan
authors.initials: R
authors.lastname: Wu
authors.affiliation: College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China.
authors.forename: Ruijue
authors.initials: R
authors.lastname: Wang
authors.affiliation: College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China.
authors.forename: Zhiyan
authors.initials: Z
authors.lastname: Hu
authors.affiliation: College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China. Electronic address: yangst@pku.edu.cn.
authors.forename: Sheng-Tao
authors.initials: ST
authors.lastname: Yang
authors.affiliation: College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China. Electronic address: luojb1971@163.com.
authors.forename: Jianbin
authors.initials: J
authors.lastname: Luo
mesh_terms: D000327:Adsorption; D003300:Copper / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009994:Osmolar Concentration; D059027:Recycling; D013455:Sulfur / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods
chemical_list: D014874:Water Pollutants, Chemical; D013455:Sulfur; D006108:Graphite; D003300:Copper
keywords: Adsorbent; Heavy metal; Hydrothermal synthesis; S-doped graphene sponge; Water treatment