Effects of wire-type and mesh-type anode current collectors on performance and electrochemistry of microbial fuel cells

Jung, Sokhee P.,Kim, Eojin,Koo, Bonyoung Elsevier 2018 CHEMOSPHERE - Vol.209 No.-

<P><B>Abstract</B></P> <P>Carbon-based material is commonly used for anodes in MFCs, but its low conductivity often limits anodic performance. Application of corrosion-resistive current collector to carbon-based anode can be a promising strategy for increasing the anodic performance. In this study, it was hypothesized increasing metal current collector improved anodic performance. Two different carbon-felt anodes with titanium wires (CF-W) or stainless steel mesh (CF-M) as a current collector were tested in a single chamber MFC. In the short-term tests such as polarization and impedance tests, CF-M with the larger current collector area (21.7 cm<SUP>2</SUP>) had 33% higher maximum power (2311 mW/m<SUP>2</SUP>), 81% lower anodic resistance (3 Ω), and 92% lower anodic impedance (1.1 Ω). However, in the long-term tests, CF-W with the smaller current collector area (0.6 cm<SUP>2</SUP>) showed higher performance in power and current generation, COD removal, and CE (51%, 10%, 11%, and 5% higher, respectively) and produced 41% higher net current in cyclic voltagramm (20.0 mA vs. 14.2 mA). This result shows that larger current collector is advantageous in short-term performance and disadvantageous in long-term performance, because the larger current collector is good for current collection, but interferes with mass transfer and microbial growth.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Two types of anodes differing in area and material of current collectors were tested. </LI> <LI> Tested carbon felt anodes with titanium wires (CF-W) or stainless steel mesh (CF-M). </LI> <LI> In short-term tests, CF-M with larger current collector showed higher performances. </LI> <LI> In the long-term tests, CF-W with smaller current collector showed higher performance. </LI> <LI> CF-M is good for current collection, but mass transfer and microbial growth inhibited. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

미생물 연료전지의 전력 발생 향상을 위한 전류 포집체 면적 증가에 대한 영향

채형원 ( Chai Hyungwon ),정석희 ( Jung Sokhee ) 한국물환경학회 2020 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2020 No.-

Microbial fuel cell (MFC) is an innovative environmental and energy system that converts organic wastewater into electrical energy. For the practical implementation of MFC as a wastewater treatment process, a number of limitations need to be overcome. Improving cathodic performance is one of the major challenges, and introduction of a current collector can be an easy and practical solution. In this study, three types of current collectors made of stainless steel (SS) were tested in a single-chamber cubic MFC. The three current collectors had different contact areas to the cathode (P 1.0 cm²; PC 4.3 cm²; PM 6.5 cm²) and increasing the contacting area enhanced the power and current generations and coulombic and energy recoveries by mainly decreasing cathodic charge transfer impedance. Application of the SS mesh to the cathode (PM) improved maximum power density, optimum current density, and maximum current density by 8.8%, 3.6%, and 6.7%, respectively, compared with P of no SS mesh. The SS mesh decreased cathodic polarization resistance by up to 16%, and cathodic charge transfer impedance by up to 39%, possibly because the SS mesh enhanced electron transport and oxygen reduction reaction.

미생물 연료전지의 전력 발생 향상을 위한 전류 포집체 면적 증가에 대한 영향

채형원 ( Chai Hyungwon ),정석희 ( Jung Sokhee ) 한국물환경학회 2020 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2020 No.-

Microbial fuel cell (MFC) is an innovative environmental and energy system that converts organic wastewater into electrical energy. For the practical implementation of MFC as a wastewater treatment process, a number of limitations need to be overcome. Improving cathodic performance is one of the major challenges, and introduction of a current collector can be an easy and practical solution. In this study, three types of current collectors made of stainless steel (SS) were tested in a single-chamber cubic MFC. The three current collectors had different contact areas to the cathode (P 1.0 cm²; PC 4.3 cm²; PM 6.5 cm²) and increasing the contacting area enhanced the power and current generations and coulombic and energy recoveries by mainly decreasing cathodic charge transfer impedance. Application of the SS mesh to the cathode (PM) improved maximum power density, optimum current density, and maximum current density by 8.8%, 3.6%, and 6.7%, respectively, compared with P of no SS mesh. The SS mesh decreased cathodic polarization resistance by up to 16%, and cathodic charge transfer impedance by up to 39%, possibly because the SS mesh enhanced electron transport and oxygen reduction reaction.

Wire-type and Mesh-type Current Collectors Improve Cathode Performance in Microbial Fuel Cell

Hyungwon CHAI,Sokhee JUNG 한국생물공학회 2020 한국생물공학회 학술대회 Vol.2020 No.10

Effects of Wire-type and Mesh-type Anode Current Collectors on Performance and Electrochemistry of Microbial Fuel Cells

Viet Hoa Huong TRAN,Sokhee JUNG 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.4

Effect of surface treatment on mechanical properties of glass fiber/stainless steel wire mesh reinforced epoxy hybrid composites

Karunagaran N.,Rajadurai A. 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.6

This paper investigates the effect of surface treatment for glass fiber, stainless steel wire mesh on tensile, flexural, inter-laminar shear and impact properties of glass fiber/ stainless steel wire mesh reinforced epoxy hybrid composites. The glass fiber fabric is surface treated either by 1 N solution of sulfuric acid or 1 N solution of sodium hydroxide. The stainless steel wire mesh is also surface treated by either electro dissolution or sand blasting. The hybrid composites are fabricated using epoxy resin reinforced with glass fiber and fine stainless steel wire mesh by hand lay-up technique at room temperature. The hybrid composite consisting of acid treated glass fiber and sand blasted stainless steel wire mesh exhibits a good combination of tensile, flexural, inter-laminar shear and impact behavior in comparison with the composites made without any surface treatment. The fine morphological modifications made on the surface of the glass fiber and stainless steel wire mesh enhances the bonding between the resin and reinforcement which inturn improved the tensile, flexural, inter-laminar shear and impact properties.

스테인레스 스틸 와이어 메쉬 보강공법의 보강조건 평가

김성훈 서울産業大學校 1999 논문집 Vol.50 No.2

Stainless steel wire mesh method(SSWM method) is a new technique for strengthening the deteriorated concrete structure and is consist of the combination with the stainless steel wire mesh for reinforcement materal and developed-permeability polymer mortar for repair materal. The strengthening effect of slab structure by SSWM method were already confirmed by the laboratory tests, but there are not any data for the reinforcement design and applicable conditions of this method. A total of 16 slab specimens with different strengthening conditions that consist of various parameters such as wire diameter, wire anchoring, chipping of concrete surface, the interval of transversal wire and thickness of mortar were tested under the three point bending test. And based on the analytical studies of test results, the optimum design method for strengthening the deteriorated concrete structures using the stainless steel wire mesh were presented.

스테인레스 스틸 와이어 메쉬로 보강된 철근콘크리트 슬래브의 휨거동

김성훈 서울産業大學校 1999 논문집 Vol.50 No.2

Steel plate reinforcement method, glass fiber reinforcement method, and carbon fiber reinforcement method and so forth were used to improve the load-resistance capacity of deteriorated-slab structure until now. These methods were introduced from foreign country but in home countries, there is not any inspection and systematic study for these reinforcement methods until now. However, neglecting the characteristics of structural behaviors and random application of reinforcement methods make it hard to anticipate the strengthening effect of these methods. Therefore, stainless steel wire mesh strengthening method that is a new technique for reinforcement of deteriorated concrete is developed as a part of research for strengthening on concrete structure. A total of 16 slab specimens with different strengthening conditions were tested under the three point bending test. And from the test results, the flexure behavior of RC slab strengthened by stainless steel wire mesh and permeability polymer mortar are investigated.

Performance and Electrochemical Characteristic of Microbial Fuel Cells with Different Anode Current Collectors

Huong TRAN,Sokhee JUNG 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10

Microbial fuel cell (MFC) is an innovative environmental and energy system that converts organic wastewater into electrical energy. For the practical implementation of MFC as a wastewater treatment process, a number of limitations need to be overcome. Improving anode performance is one of the major challenges, and introduction of a current collector can be an easy and practical solution. High-performance electrode materials make it possible to achieve high power generation of MFC systems by reducing internal resistance. Carbon-based materials are generally used for the MFC anode electrode, but their conductivity is much lower than metal materials. In this study, it was hypothesized increasing metal current collector areas improve anodic performance. The performance of the carbon felt anode was compared using titanium wire and stainless steel mesh as a current collector. In the IV polarization test, maximum power density, maximum current density and optimum current density were 33%, 34% and 30% higher in CF-M (2,311 ㎽/㎡, 16,815 ㎃/㎡ and 7,651 ㎃/㎡) than CF-W (1,737 ㎽/㎡, 12,566 ㎃/㎡ and 5,874 ㎃/㎡), respectively. However the stainless steel mesh used as a current collector of CF-M inhibits microbial growth and adhesion on the carbon felt and reduces mass transfer because it decreases the surface area of carbon felt. Therefore, when using stainless steel mesh as a current collector, it should be used in consideration of the problem of microbial adhesion.

일렉트로슬래그 클래딩으로 그물망 용접조직을 갖는 새로운 420계 스테인리스강 스트립재의 질소함량과 냉간압하량에 따른 기계적 특성 변화

정재영(Jae-Young Jung) 대한용접·접합학회 2017 대한용접·접합학회지 Vol.35 No.6

In this study, we investigated the mechanical properties of new 420 stainless steel strips as a function of nitrogen content and cold rolling reduction. Also, the results of the tensile and thermal fatigue tests using electroslag cladding specimens under a given welding condition were as follows. As-welded structures in which the delta ferrite is present in the form of a mesh are obtained in the alloy composition range in which about 5% delta ferrite is present in the Schaeffler diagram based on Cr equivalent and Ni equivalent. The softening temperature of new 420 stainless steel alloy designed as a mesh as-welded structure was determined to be 680-730℃ as a result of using cold rolled steel at 10-90% reduction. The ratio of 600℃ to room temperature tensile yield strength of weld metal was ~0.37 for the lowest N specimen and ~0.485 for the highest N specimen. However, high temperature ductility deteriorated with increasing N content. The presence of welding beads between the weld metal also reduced the elongation at room and high temperature rather than yield and tensile strength. The thermal fatigue characteristics are almost equal or better than those of the same materials prepared by the submerged welding method.