title: Trace heavy metal ions promoted extracellular electron transfer and power generation by Shewanella in microbial fuel cells.
abstract: Although microbial fuel cells (MFCs) is considered as one of the most promising technology for renewable energy harvesting, low power output still accounts one of the bottlenecks and limits its further development. In this work, it is found that Cu(2+) (0.1μgL(-1)-0.1mgL(-1)) or Cd(2+) (0.1μgL(-1)-1mgL(-1)) significantly improve the electricity generation in MFCs. The maximum power output achieved with trace level of Cu(2+) (∼6nM) or Cd(2+) (∼5nM) is 1.3 times and 1.6 times higher than that of the control, respectively. Further analysis verifies that addition of Cu(2+) or Cd(2+) effectively improves riboflavin production and bacteria attachment on the electrode, which enhances bacterial extracellular electron transfer (EET) in MFCs. These results unveil the mechanism for power output enhancement by Cu(2+) or Cd(2+) addition, and suggest that metal ion addition should be a promising strategy to enhance EET as well as power generation of MFCs.
authors.affiliation: Biofuels Institute, School of the Environment, Jiangsu University, Zhenjiang 212013, China; College of Biotechnology and Pharmaceutical Engineering and Bioenergy Research Institute, Nanjing TECH University, Nanjing 210095, China.
authors.forename: Yu-Shang
authors.initials: YS
authors.lastname: Xu
authors.affiliation: Guangzhou Institute of Energy Conversion, Key Laboratory of Renewable Energy, Chinese Academy of Science, Guangzhou, Guangdong 510640, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zheng
authors.affiliation: College of Biotechnology and Pharmaceutical Engineering and Bioenergy Research Institute, Nanjing TECH University, Nanjing 210095, China.
authors.forename: Xiao-Yu
authors.initials: XY
authors.lastname: Yong
authors.affiliation: Biofuels Institute, School of the Environment, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Dan-Dan
authors.initials: DD
authors.lastname: Zhai
authors.affiliation: Biofuels Institute, School of the Environment, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Rong-Wei
authors.initials: RW
authors.lastname: Si
authors.affiliation: Biofuels Institute, School of the Environment, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Li
authors.affiliation: Biofuels Institute, School of the Environment, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Yang-Yang
authors.initials: YY
authors.lastname: Yu
authors.affiliation: Biofuels Institute, School of the Environment, Jiangsu University, Zhenjiang 212013, China. Electronic address: ycyong@ujs.edu.cn.
authors.forename: Yang-Chun
authors.initials: YC
authors.lastname: Yong
mesh_terms: D001674:Bioelectric Energy Sources / Q000382:microbiology*; D004560:Electricity; D004566:Electrodes; D004579:Electron Transport; D004583:Electrons; D020450:Heavy Ions; D019216:Metals, Heavy / Q000737:chemistry*; D012256:Riboflavin / Q000096:biosynthesis; D020592:Shewanella / Q000254:growth & development / Q000378:metabolism*
chemical_list: D019216:Metals, Heavy; D012256:Riboflavin
keywords: Bioelectrochemical systems; Biofilm; Extracellular electron transfer; Heavy metal ions; Microbial fuel cells; Shewanella oneidensis