title: Layer-by-layer construction of graphene-based microbial fuel cell for improved power generation and methyl orange removal.
abstract: Development of highly efficient anode is critical for enhancing the power output of microbial fuel cells (MFCs). The aim of this work is to investigate whether modification of carbon paper (CP) anode with graphene (GR) via layer-by-layer assembly technique is an effective approach to promote the electricity generation and methyl orange removal in MFCs. Using cyclic voltammetry and electrochemical impedance spectroscopy, the GR/CP electrode exhibited better electrochemical behavior. Scanning electron microscopy results revealed that the surface roughness of GR/CP increased, which was favorable for more bacteria to attach to the anode surface. The MFCs equipped with GR/CP anode achieved a stable maximum power density of 368 mW m(-2) under 1,000 Ω external resistance and a start time for the initial maximum voltage of 180 h, which were, respectively, 51 % higher and 31 % shorter than the corresponding values of the MFCs with blank anode. The anode and cathode polarization curves revealed negligible difference in cathode potentials but obviously difference in anode potentials, indicating that the GR-modified anode other than the cathode was responsible for the performance improvement of MFC. Meanwhile, compared with MFCs with blank anode, 11 % higher decolorization efficiency and 16 % higher the chemical oxygen demand removal rate were achieved in MFC with GR-modified anode during electricity generation. This study might provide an effective way to modify the anode for enhanced electricity generation and efficient removal of azo dye in MFCs.
authors.affiliation: School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control Ministry of Education, Henan Normal University, Xinxiang, 453007, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.forename: Yanrui
authors.initials: Y
authors.lastname: Cui
authors.forename: Hong
authors.initials: H
authors.lastname: Song
authors.forename: Jianhui
authors.initials: J
authors.lastname: Sun
mesh_terms: D001391:Azo Compounds / Q000302:isolation & purification*; D001674:Bioelectric Energy Sources; D011211:Electric Power Supplies; D006108:Graphite / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D013056:Spectrophotometry, Ultraviolet
chemical_list: D001391:Azo Compounds; C100258:methyl orange; D006108:Graphite