Decorated carbon-based biocathode to improve electromethanosynthesis in a two-chamber microbial electrolysis cells (MECs)
Microbial electromethanogenesis,relying on electrochemically active biofilm on biocathode to convert carbon dioxide to methane,provides a novel approach for renewable energy storage.One key factor that governs electron exchange and methane formation efficiencies is the electrode material.To promote methane production,a biocathode via modifying plain carbon stick with a layer of graphite felt (GF) (hereafter referred as hybrid GF-biocathode) was developed and evaluated in a two-chamber microbial electrolysis cells (MEC).Methane production with hybrid GF-biocathode reached 80.9 mL/L at the potential of-l.4 V after 24 h of incubation with coulombic efficiency of 194.4%.The tests by flushing three substrates (CO2,N2 and H2-CO280∶ 20) revealed that direct electron transfer rather than intermediate H2 contributed more to the electromethanogenesis.Cyclic voltammetry showed that GF enhanced the microbial electrocatalysis activity and reduced the cathode overpotential needed for methane production.Scanning electron microscope and fluorescence in situ hybridization analysis confirmed that the three-dimensional GF afforded the abundant space for the growth of electroactive microorganisms and promoted the electron exchange (e.g.cathode-to-cell etc.) via severing as artificial pili.This study reveals that GF with the open structure and high conductivity has the substantial potential to upgrade electromethanogencsis efficiency.
Microbial electrolysis cells (MEC) graphite felt (GF) carbon dioxide methane electromethanogenesis
G.Y.Zhen X.Q.Lu T.Kobayashi K.Q.Xu
School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR C Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan
国际会议
The 15th IWA World Conference on Anaerobic Digestion( 第15届IWA世界厌氧大会)
北京
英文
195-198
2017-10-17（万方平台首次上网日期，不代表论文的发表时间）