title: Metallic State FeS Anchored (Fe)/Fe3O4/N-Doped Graphitic Carbon with Porous Spongelike Structure as Durable Catalysts for Enhancing Bioelectricity Generation.
abstract: The critical issues in practical application of microbial fuel cells (MFCs) for wastewater treatment are the high cost and poor activity and durability of precious metal catalysts. To alleviate the activity loss and kinetic barriers for oxygen reduction reaction (ORR) on cathode, (Fe)/Fe3O4/FeS/N-doped graphitic carbon ((Fe)/Fe3O4/FeS/NGC) is prepared as ORR catalyst through a one-step method using waste pomelo skins as carbon source. Various characterization techniques and electrochemical analyses are conducted to illustrate the correlation between structural characteristics and catalytic activity. MFCs with Fe/Fe3O4/FeS/NGC (900 °C) cathode produces the maximum power density of 930 ± 10 mW m-2(Pt/C of 489 mW m-2) and maintains a good long-term durability, which only declines 18% after 90 day operation. Coulombic efficiency (22.2%) obtained by Fe/Fe3O4/FeS/NGC (900 °C) cathode is significantly higher than that of Pt/C (17.3%). Metallic state FeS anchored in porous NGC skeleton can boost electron transport through the interconnected channels in spongelike structure to improve catalytic activity. Charge delocalization of C atoms can be strengthened by N atoms incorporation into carbon skeleton, which correspondingly contributes to the O2chemisorptions and O-O bond weakening during ORR. Energetically existed active components (Fe and N species) are more efficient than Pt to trap and consume electrons in catalyzing ORR in wastewater containing Pt-poisoning substances (bacterial metabolites). (Fe)/Fe3O4/FeS/NGC catalysts with the advantages of durable power outputs and environmental-friendly raw material can cover the shortages of Pt/C and provide an outlook for further applications of these catalysts.
authors.affiliation: Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University , Harbin 150080, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Xu
authors.affiliation: Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University , Harbin 150080, China.|School of Civil Engineering, Heilongjiang Institute of Technology , Harbin 150050, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Dai
authors.affiliation: College of Aerospace and Civil Engineering, Harbin Engineering University , Harbin, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Yu
authors.affiliation: Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University , Harbin 150080, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Hao
authors.affiliation: Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University , Harbin 150080, China.
authors.forename: Yaqiang
authors.initials: Y
authors.lastname: Duan
authors.affiliation: Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University , Harbin 150080, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University , Harbin 150080, China.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University , Harbin 150080, China.
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University , Harbin 150080, China.
authors.forename: Jinlong
authors.identifier: http://orcid.org/0000-0003-0651-761X
authors.initials: J
authors.lastname: Zou
keywords: biofilm overgrowth; durability; interconnected channels; power density; waste biomass