Simultaneous removal of Cr(VI) and 4-chlorophenol through photocatalysis by a novel anatase/titanate nanosheet composite: Synergetic promotion effect and autosynchronous doping

JOURNAL OF HAZARDOUS MATERIALS

卷:317

Article

Liu, Wen^1,2,3  Sun, Weiling²  Borthwick, Alistair G. L.⁴  Wang, Ting²  Li, Fan³  Guan, Yidong^1,3 

[1] Nanjing Univ Informat Sci & Technol, Sch Environm Sci & Engn, Jiangsu Key Lab Atmospher Environm Monitoring & P, Nanjing 210044, Jiangsu, Peoples R China

[2] Peking Univ, Key Lab Water & Sediment Sci, Minist Educ, Dept Environm Engn, Beijing 100871, Peoples R China

[3] Auburn Univ, Dept Civil Engn, Environm Engn Program, Auburn, AL 36849 USA

[4] Univ Edinburgh, Sch Engn, Kings Buildings, Edinburgh EH9 3JL, Midlothian, Scotland

关键词: Titanate nanosheet;    Synergetic promotion;    Autosynchronous doping;    Photocatalysis;    Combined pollution;   

DOI  :  10.1016/j.jhazmat.2016.06.002

来源: Elsevier

【 摘 要 】

Clean-up of wastewaters with coexisting heavy metals and organic contaminants is a huge issue worldwide. In this study, a novel anatase/titanate nanosheet composite material (labeled as TNS) synthesized through a one-step hydrothermal reaction was demonstrated to achieve the goal of simultaneous removal of Cr(VI) and 4-cholophenol (4-CP) from water. TEM and XRD analyses indicated the TNS was a nano-composite of anatase and titanate, with anatase acting as the primary photocatalysis center and titanate as the main adsorption site. Enhanced photocatalytic removal of co-existent Cr(VI) and 4-CP was observed in binary systems, with apparent rate constants (k(1)) for photocatalytic reactions of Cr(VI) and 4-CP about 3.1 and 2.6 times of that for single systems. In addition, over 99% of Cr(VI) and 4-CP was removed within 120 min through photocatalysis by TNS at pH 7 in the binary system. Mechanisms for enhanced photocatalytic efficiency in the binary system are identified as: (1) a synergetic effect on the photo-reduction of Cr(VI) and photo-oxidation of 4-CP due to efficient separation of electron-hole pairs, and (2) autosynchronous doping because of reduced Cr(III) adsorption onto TNS. Furthermore, TNS could be efficiently reused after a simple acid-base treatment. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

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