Graphene/biofilm composites for enhancement of hexavalent chromium reduction and electricity production in a biocathode microbial fuel cell.
In this study, a simple method of biocathode fabrication in a Cr(VI)-reducing microbial fuel cell (MFC) is demonstrated. A self-assembling graphene was decorated onto the biocathode microbially, constructing a graphene/biofilm, in situ. The maximum power density of the MFC with a graphene biocathode is 5.7 times that of the MFC with a graphite felt biocathode. Cr(VI) reduction was also enhanced, resulting in 100% removal of Cr(VI) within 48h, at 40mg/L Cr(VI), compared with only 58.3% removal of Cr(VI) in the MFC with a graphite felt biocathode. Cyclic voltammogram analyses showed that the graphene biocathode had faster electron transfer kinetics than the graphite felt version. Energy dispersive spectrometer (EDS) and X-ray photoelectron spectra (XPS) analysis revealed a possible adsorption-reduction mechanism for Cr(VI) reduction via the graphene biocathode. This study attempts to improve the efficiency of the biocathode in the Cr(VI)-reducing MFC, and provides a useful candidate method for the treatment of Cr(VI) contaminated wastewater, under neutral conditions.
State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, PR China; College of Life Science and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China; Jiangsu Branch of China Academy of Science & Technology Development, Nanjing, PR China.
Tian-Shun
TS
Song
State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, PR China; College of Life Science and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China.
Yuejuan
Y
Jin
State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, PR China; College of Life Science and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China.
Jingjing
J
Bao
College of Pharmacy, Yanbian University, Yanji 133002, PR China. Electronic address: kangdz@ybu.edu.cn.
Dongzhou
D
Kang
State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, PR China; College of Life Science and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China; Jiangsu Branch of China Academy of Science & Technology Development, Nanjing, PR China; College of Pharmacy, Yanbian University, Yanji 133002, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing 211816, PR China. Electronic address: xiej@njtech.edu.cn.
Jingjing
J
Xie
D001674:Bioelectric Energy Sources / Q000382:microbiology; D018441:Biofilms / Q000254:growth & development*; D002857:Chromium / Q000737:chemistry*; D004560:Electricity; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D013499:Surface Properties; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
D014874:Water Pollutants, Chemical; D002857:Chromium; C074702:chromium hexavalent ion; D006108:Graphite
Biocathode; Cr(VI) reduction; Graphene; Microbial fuel cell