title: Uneven biofilm and current distribution in three-dimensional macroporous anodes of bio-electrochemical systems composed of graphite electrode arrays.
abstract: A 3-D macroporous anode was constructed using different numbers of graphite rod arrays in fixed-volume bio-electrochemical systems (BESs), and the current and biofilm distribution were investigated by dividing the 3-D anode into several subunits. In the fixed-volume chamber, current production was not significantly improved after the electrode number increased to 36. In the case of 100 electrodes, a significant uneven current distribution was found in the macroporous anode. This was attributed to a differential pH distribution, which resulted from proton accumulation inside the macroporous anode. The pH distribution influenced the biofilm development and led to an uneven biofilm distribution. With respect to current generation, the uneven distribution of both the pH and biofilm contributed to the uneven current distribution. The center had a low pH, which led to less biofilm and a lower contribution to the total current, limiting the performance of the BESs.
authors.affiliation: Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 40003, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400030, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 40003, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400030, China.
authors.forename: Linbin
authors.initials: L
authors.lastname: Hu
authors.affiliation: Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 40003, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400030, China. Electronic address: liangzhang@cqu.edu.cn.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 40003, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400030, China.
authors.forename: Ding-Ding
authors.initials: DD
authors.lastname: Ye
authors.affiliation: Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 40003, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400030, China.
authors.forename: Xun
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 40003, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400030, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liao
mesh_terms: D001674:Bioelectric Energy Sources / Q000382:microbiology*; D018441:Biofilms; D004566:Electrodes; D004867:Equipment Design; D006108:Graphite; D006863:Hydrogen-Ion Concentration; D016062:Porosity
chemical_list: D006108:Graphite
keywords: 3-D macroporous electrode; Bio-electrochemical system; Biofilm distribution; Current distribution; Proton transfer