Şebnem Cingisiz, Emin Arca, Rezan Demir‐Cakan

ChemElectroChem • 2024

<jats:title>Abstract</jats:title><jats:p>Silicon (Si) anode is of considerable interest in Li‐ion batteries due to its high theoretical capacity (4200 mAh g<jats:sup>−1</jats:sup>), abundant reserves in the earth, and environmentally friendly nature. Although Si anode has significant advantages, the electrode is prone to cracks due to large volume changes in its structure during discharge cycles in Li‐ion batteries. Rapid capacity degradation occurs as a result of deterioration of the structural integrity of the electrode. Although binders are known to contribute to improving the electrochemical performance of anode materials, polyvinylidene fluoride (PVdF) used in commercial Li‐ion batteries cannot maintain the mechanical stability of the Si anode during cycles due to weak Van der Waals interactions, which also dissolves in the flammable, explosive and volatile solvent N‐Methyl‐2‐pyrrolidone (NMP). In this study, low cost, sustainable and environmentally green psyllium gum (PG) was extracted from psyllium husk and tested for the first time as a water‐soluble binder for Si anode. According to galvanostatic charge/discharge tests, the Si‐PG anode exhibits a capacity of 1415 mAh g<jats:sup>−1</jats:sup> after 100 cycles at a voltage range of 0.01–1.5 V and current density of C/2, which is almost 3 times higher than the Si‐PVdF anode (494 mAh g<jats:sup>−1</jats:sup>).</jats:p>

Dongling Jia, Jianguo Huang

New Journal of Chemistry • 0

<p>A nanofibrous silicon/carbon composite derived from a cellulose substance was fabricated, showing enhanced electrochemical performances as an anode material for lithium-ion batteries.</p>

Giulia Massaglia, Adriano Sacco, Angelica Chiodoni et al.

Nanomaterials • 0

<jats:p>The aim of this work is the optimization of electrospun polymeric nanofibers as an ideal reservoir of mixed electroactive consortia suitable to be used as anodes in Single Chamber Microbial Fuel Cells (SCMFCs). To reach this goal the microorganisms are directly embedded into properly designed nanofibers during the electrospinning process, obtaining so called nanofiber-based bio-composite (bio-NFs). This research approach allowed for the designing of an advanced nanostructured scaffold, able to block and store the living microorganisms inside the nanofibers and release them only after exposure to water-based solutions and electrolytes. To reach this goal, a water-based polymeric solution, containing 5 wt% of polyethylene oxide (PEO) and 10 wt% of environmental microorganisms, is used as the initial polymeric solution for the electrospinning process. PEO is selected as the water-soluble polymer to ensure the formation of nanofiber mats offering features of biocompatibility for bacteria proliferation, environment-friendliness and, high ionic conductivity. In the present work, bio-NFs, based on living microorganisms directly encapsulated into the PEO nanofiber mats, were analyzed and compared to PEO-NFs made of PEO only. Scanning electron microscopy allowed researchers to confirm the rise of a typical morphology for bio-NFs, evidencing the microorganisms’ distribution inside them, as confirmed by fluorescence optical microscopy. Moreover, the latter technique, combined with optical density measurements, allowed for demonstrating that after electrospinning, the processed microorganisms preserved their proliferation capability, and their metabolic activity after exposure to the water-based electrolyte. To demonstrate that the energy-production functionality of exo-electrogenic microorganisms was preserved after the electrospinning process, the novel designed nanomaterials, were directly deposited onto carbon paper (CP), and were applied as anode electrodes in Single Chamber Microbial Fuel Cells (SCMFCs). It was possible to appreciate that the maximum power density reached by bio-NFs, which resulted in being double of the ones achieved with PEO-NFs and bare CP. SCMFCs with bio-NFs applied as anodic electrodes reached a current density value, close to (250 ± 5.2) mA m−2, which resulted in being stable over time and was comparable with the one obtained with carbon-based electrode, thus confirming the good performance of the whole device.</jats:p>

En Ren Zhang, Qiang Ji, Lei Liu

Applied Mechanics and Materials • 0

<jats:p>Microbial fuel cells with brush bio-anode and bio-cathode made of PAN-based carbon fibers were constructed, and the electricity production was investigated. Experimental results indicate that both the anode and the cathode could be catalyzed by mixed bacterial cultures. Oxygen-reduction at the cathode could be carried out effectively with the assistance of catalytic action by bacteria, enhancing the electrochemical properties of the cathode. Stable electricity production could be obtained with maximum power 5.6 mW (corresponding power density ~2.1 W/m<jats:sup>3</jats:sup> MFC volume) when operating MFC in continuous flow mode. PAN-based carbon fibers were shown to be suitable electrode materials for MFCs, especially in systems for the future applications.</jats:p>

Irene Bavasso, Daniele Montanaro, Elisabetta Petrucci et al.

Sustainability • 0

<jats:p>In this work, the feasibility of the Shortcut Biological Nitrogen Removal (SBNR) in the anodic chamber of a Microbial Fuel Cell (MFC) was investigated. Thirty day experiments were carried out using synthetic wastewaters with a Total Organic Carbon vs. nitrogen ratio (TOC/N) ranging from 0.1 to 1. Ammonium, nitrite, nitrate, pH, and TOC were daily monitored. Results showed that microaerobic conditions in the anodic chamber favored the development of nitritation reaction, due to oxygen transfer from the cathodic chamber through the membrane. Nitritation was found to depend on TOC/N ratio: at TOC/N equal to 0.1 an ammonium removal efficiency of up to 76% was observed. Once the oxygen supply to the cathodic chamber was stopped, denitritation occurred, favored by an increase of the TOC/N ratio: a nitrite removal of 80.3% was achieved at TOC/N equal to 0.75. The presence of nitrogen species strongly affected the potential of the electrochemical system: in the nitritation step, the Open Circuit Voltage (OCV) decreased from 180 mV to 21 mV with the decrease of the TOC/N ratio in the investigated range. Lower OCV values were observed in the denitritation steps since the organic carbon acted as the energy source for the conversion of nitrite to nitrogen gas. A kinetic analysis was also performed. Monod and Blackman models described the ammonium and the organic carbon removal processes well during the nitritation step, respectively, while Blackman-Blackman fitted experimental results of the denitritation step better.</jats:p>

P. T. Tran, L. V. H. Nguyen, H. Nguyen et al.

AIMS Bioengineering • 2016

Microbial fuel cells are a recently emerging technology that promises a number of applications in energy recovery, environmental treatment and monitoring. In this study, we investigated the effect of inoculating sources on the enrichment of electrochemically active bacterial consortia in sensor-typed microbial fuel cells (MFCs). Several MFCs were constructed, operated with modified artificial wastewater and inoculated with different microbial sources from natural soil, natural mud, activated sludge, wastewater and a mixture of those sources. After enrichment, the MFCs inoculated with the natural soil source generated higher and more stable currents (0.53±0.03 mA), in comparisons with the MFCs inoculated with the other sources. The results from denaturing gradient gel electrophoresis (DGGE) showed that there were significant changes in bacterial composition from the original inocula to the enriched consortia. Even more interestingly, Pseudomonas sp. was found dominant in the natural soil source and also in the corresponding enriched consortium. The interactions between Pseudomonas sp. and other species in such a community are probably the key for the effective and stable performance of the MFCs.

Jian-hua Wang, Lifeng Chen, Weixu Dong et al.

ACS Nano • 2023

Uneven zinc (Zn) deposition typically leads to uncontrollable dendrite growth, which renders an unsatisfactory cycling stability and Coulombic efficiency (CE) of aqueous zinc ion batteries (ZIBs), restricting their practical application. In this work, a lightweight and flexible three-dimensional (3D) carbon nanofiber architecture with uniform Zn seeds (CNF-Zn) is prepared from bacterial cellulose (BC), a kind of biomass with low cost, environmental friendliness, and abundance, as a host for highly reversible Zn plating/stripping and construction of high-performance aqueous ZIBs. The as-prepared 3D CNF-Zn with a porous interconnected network significantly decreases the local current density, and the functional Zn seeds provide uniform nuclei to guide the uniform Zn deposition. Benefiting from the synergistic effect of Zn seeds and the 3D porous framework in the flexible CNF-Zn host, the electrochemical performance of the as-constructed ZIBs is significantly improved. This flexible 3D CNF-Zn host delivers a high and stable CE of 99.5% over 450 cycles, ensuring outstanding rate performance and a long cycle life of over 500 cycles at 4 A g-1 in the CNF-Zn@Zn//NaV3O8·1.5H2O full battery. More importantly, owing to the flexibility of the 3D CNF-Zn host, the as-assembled pouch cell shows outstanding mechanical flexibility and excellent energy storage performance. This strategy of producing readily accessible carbon from biomass can be employed to develop advanced functional nanomaterials for next-generation flexible energy storage devices.

Jiaxin Xu, Zhanying Liu, Fang Zhang et al.

RSC Advances • 2020

Hybrid ion capacitors (HICs) based on insertion reactions have attracted considerable attention due to their energy density being much higher than that of the electrical double-layer capacitors (EDLCs). However, the development of hybrid ion capacitors with high energy density at high power density is a big challenge due to the mismatch of charge storage capacities and electrode kinetics between the battery-type anode and capacitor-type cathode. In this work, N and O dual doped carbon nanofibers (N,O-CNFs) were combined with carbon nanotubes (CNTs) to compose a complex carbon anode. N,O dual doping effectively tuned the functional group and surface activity of the CNFs while the integration of CNTs increased the extent of graphitization and electrical conductivity. The carbon cathode with high specific surface area and high capacity was obtained by the activation of CNFs (A-CNFs). Finally, a hybrid sodium ion capacitor was constructed by the double carbon electrode, which showed a superior electrochemical capacitive performance. The as-assembled HIC device delivers a maximum energy density of 59.2 W h kg−1 at a power density of 275 W kg−1, with a high energy density of 38.7 W h kg−1 at a power density of 5500 W kg−1.

Mani Pujitha Illa, A. Pathak, C. Sharma et al.

ACS Applied Energy Materials • 2020

An increasing demand for lithium-ion batteries with high energy storage and a high-power rating, to enable applications such as electric vehicles, demands electrode materials with large charge stor...

Si-Jie Jiang, Yan-Song Xu, Xiao-Wen Sun et al.

Journal of the American Chemical Society • 2025

Lignocellulosic biomass-derived pyrolysis hard carbon (LCB-HC) shows promising commercial potential as an anode material for sodium-ion batteries (SIBs). LCB compromises multiple biopolymer carbon sources, including cellulose, hemicellulose, and lignin, which influence the formation and microstructure of pyrolysis HC. However, the poor plateau kinetics of LCB-HC is one of the main obstacles that severely limits its energy density with high power density, which could be attributed to the narrow interlayer distance and the lack of abundant closed pores for the intercalation/filling of Na+. Herein, we proposed a bottom-up approach to tailoring the microstructure of LCB-HC by regulating the components of the LCB precursor at the molecular level using bioenzymes secreted by lignocellulolytic bacteria. This mild and efficient enzymatic hydrolysis pathway partially depolymerized the biopolymers of basswood specifically, thereby enabling the construction of a small curved-graphite domain architecture with increased closed pores and an enlarged interlayer distance of LCB-HC, benefiting the low-voltage plateau Na+ storage with accelerated kinetics. As a result, the basswood-derived HC delivers a reversible capacity of 366.4 mAh g-1 and performed remarkable plateau capacity retainability with a high proportion of 74.3% even with increased current density to 1000 mA g-1. Such a microbial-chemistry-assisted approach provided insights into tailoring the microstructure of LCB-HC to construct high-performance SIB anode materials.

Dejwikom Theprattanakorn, S. Pongha, Likkhasit Wannasen et al.

International Journal of Energy Research • 2022

In this research, Fe‐MOF (MIL‐53 [Fe]) was synthesized by solvothermal and applied as an anode of lithium‐ion batteries (LIBs). Carbonaceous material from pyrolyzed bacterial cellulose (pBC) was incorporated in the solvothermal synthesis of MIL‐53(Fe) to improve its morphology and electrochemical properties. The MIL‐53(Fe) with pBC addition (MIL‐53(Fe)@pBC) exhibited reduced particle size and size distribution, larger surface area and pore volume, and modified crystal shape and interior structure. The incorporation also altered the functional group of the dicarboxylic ligand and formed a thin carbon layer coating which enhanced electrical conductivity significantly. The refined microstructure of the MIL‐53(Fe)@pBC compared to the pure MIL‐53(Fe) was proved to enhance the electrochemical activities of the LIB cells. The specific capacity, rate capability, and cyclic performance were boosted with pBC addition due to the increased ion diffusion kinetics in the lithiation/delithiation process. Interestingly, the MIL‐53(Fe)@pBC anode showed a peculiar increase in the reversible capacity with LIB cycles after the initial capacity fading. The analysis after the 100th cycle suggested that the lithiation/delithiation process was mediated by phase transformation through the Li+ storage mechanism. This work has shown that the MIL‐53(Fe)@pBC is an excellent candidate for anode materials in LIBs with high efficiency at long life cycles.

Zhenzhen Yang, Hongna Li, Na Li et al.

International Journal of Environmental Research and Public Health • 2022

Microbial fuel cells (MFCs) could achieve the removal of antibiotics and generate power in the meantime, a process in which the bacterial community structure played a key role. Previous work has mainly focused on microbes in the anode, while their role in the cathode was seldomly mentioned. Thus, this study explored the bacterial community of both electrodes in MFCs under sulfadiazine (SDZ) pressure. The results showed that the addition of SDZ had a limited effect on the electrochemical performance, and the maximum output voltage was kept at 0.55 V. As the most abundant phylum, Proteobacteria played an important role in both the anode and cathode. Among them, Geobacter (40.30%) worked for power generation, while Xanthobacter (11.11%), Bradyrhizobium (9.04%), and Achromobacter (7.30%) functioned in SDZ removal. Actinobacteria mainly clustered in the cathode, in which Microbacterium (9.85%) was responsible for SDZ removal. Bacteroidetes, associated with the degradation of SDZ, showed no significant difference between the anode and cathode. Cathodic and part of anodic bacteria could remove SDZ efficiently in MFCs through synergistic interactions and produce metabolites for exoelectrogenic bacteria. The potential hosts of antibiotic resistance genes (ARGs) presented mainly at the anode, while cathodic bacteria might be responsible for ARGs reduction. This work elucidated the role of microorganisms and their synergistic interaction in MFCs and provided a reference to generate power and remove antibiotics using MFCs.

Xiangmei Wang, X. Xiao, Chuntao Chen et al.

Dalton Transactions • 2023

Carbon-based materials have received wide attention as electrodes for energy storage and conversion owing to their rapid mass transfer processes, outstanding electronic conductivities, and high stabilities. Here, sulfur-doped carbonized bacterial cellulose (S-CBC) was prepared as a high-performance anode for sodium-ion batteries (SIBs) by simultaneous carbonization and sulfidation using the bacterial cellulose membrane produced by microbial fermentation as the precursor. Doping sublimed sulfur powder into CBC results in a greater degree of disorder and defects, buffering the volume expansion during the cycle. Significantly, the three-dimensional (3D) network structure of bacterial cellulose endows S-CBC with flexible self-support. As an anode for sodium ion batteries, S-CBC exhibits a high specific capacity of 302.9 mA h g-1 at 100 mA g-1 after 50 cycles and 177.6 mA h g-1 at 2 A g-1 after 1000 cycles. Compared with the CBC electrode, the S-CBC electrode also exhibits enhanced rate performance in sodium storage. Moreover, theoretical simulations reveal that Na+ has good adsorption stability and a faster diffusion rate in S-CBC. The doping of the S element introduces defects that enlarge the interlayer distance, and the synergies of adsorption and bonding are the main reasons for its high performance. These results indicate the potential application prospects of S-CBC as a flexible binder-free electrode for high-performance SIBs.

Madhumita Mukhopadhyay, Jayanta Mukhopadhyay, Abhijit Das Sharma et al.

ECS Transactions • 2009

<jats:p>In SOFC, a novel Ni-YSZ cermet developed through electroless technique is used as an anode as well as anode active layer (AAL). In the present investigation, thickness of such AAL (varied in the range 15 - 140 micrometer) is optimized sequentially for fabricating high performance single cell. The fabrication technique involves tape casting followed by room temperature lamination to form the half cells. Effect of sintering temperature of half cells on the electrochemical performance has been carried out in the range of 1300 degC to 1400 degC. A typical I-V characteristics of coupon cell (active area of ~ 0.3 cm2) sintered at 1400 degC with an optimum AAL thickness show current density of ~ 3 A/cm2 and power density of ~ 2 W/cm2 at 0.7 V and 800 degC. Electrochemical performances of single cells using only electroless anode are also evaluated for comparison. Microstructures of these single cells are correlated with the electrochemical performances.</jats:p>

Ermete Antolini

Catalysts • 0

<jats:p>To enhance the contact between the electrolyte (source of O2−) and the carbon fuel in solid oxide–direct carbon fuel cells (SO-DCFCs), molten metals and molten salts were used in the anode chamber. Oxygen ions can dissolve and be transported in the molten medium to the anode three-phase boundary to reach and oxidize the carbon particles. To improve the sluggish kinetics of the electrochemical oxidation of carbon, the same molten media can act as redox mediators. Moreover, using a liquid metal/salt anode, tolerant to fuel impurities, the negative effect of carbon contaminants on cell performance is mitigated. In this work, an overview of SO-DCFCs with liquid metals, liquid carbonates, and mixed liquid metals/liquid carbonates in the anode chamber is presented and their performance was compared to that of conventional SO-DCFCs.</jats:p>

Xuejiao Liu, Shixiong Li, Jiantao Zai et al.

Dalton Transactions • 0

<p>The enormous volume expansion during cycling and poor electron conductivity of SnS₂ limit its cycling stability and high rate capability.</p>

Thomas Tao, Mike Slaney, Linda Bateman et al.

ECS Transactions • 2007

<jats:p>The Liquid Tin Anode Solid Oxide Fuel Cell (LTA-SOFC) is a modified version of SOFC that allows the direct conversion of carbonaceous fuels. The LTA-SOFC uses conventional SOFC electrolytes and cathodes but its anode is liquid tin allowing direct oxidization of fuel without reforming or other fuel processing. A porous ceramic separator was introduced in CellTech Power's Gen 2 and Gen 3 LTA-SOFC designs. The separator holds the liquid tin anode in place while allowing free exchange of fuel molecules and products. This paper describes anode polarization of LTA-SOFC and a capillary model for porous tin anode separator</jats:p>

Ziyan Zheng, Shaojie Guo, Mengyu Yan et al.

Advanced Materials • 2023

<jats:title>Abstract</jats:title><jats:p>Aqueous zinc‐ion batteries (AZIBs) offer promising prospects for large‐scale energy storage due to their inherent abundance and safety features. However, the growth of zinc dendrites remains a primary obstacle to the practical industrialization of AZIBs, especially under harsh conditions of high current densities and elevated temperatures. To address this issue, a Janus separator with an exceptionally ultrathin thickness of 29 µm is developed. This Janus separator features the bacterial cellulose (BC) layer on one side and Ag nanowires/bacterial cellulose (AgNWs/BC) layer on the other side. High zincophilic property and excellent electric/thermal conductivity of AgNWs make them ideal for serving as an ion pump to accelerate Zn<jats:sup>2+</jats:sup> transport in the electrolyte, resulting in greatly improved Zn<jats:sup>2+</jats:sup> conductivity, deposition of homogeneous Zn nuclei, and dendrite‐free Zn. Consequently, the Zn||Zn symmetrical cells with the Janus separator exhibit a stable cycle life of over 1000 h under 80 mA cm<jats:sup>−2</jats:sup> and are sustained for over 600 h at 10 mA cm<jats:sup>−2</jats:sup> under 50 °C. Further, the Janus separator enables excellent cycling stability in AZIBs, aqueous zinc‐ion capacitors (AZICs), and scaled‐up flexible soft‐packaged batteries. This study demonstrates the potential of functional separators in promoting the application of aqueous zinc batteries, particularly under harsh conditions.</jats:p>

Rong Liu, Lina Ma, Gudan Niu et al.

Particle &amp; Particle Systems Characterization • 2017

<jats:title>Abstract</jats:title><jats:p>Ti‐doped FeOOH quantum dots (QD) decorated on graphene (GN) sheets are designed and fabricated by a facile and scalable synthesis route. Importantly, the Ti‐doped FeOOH QD/GN are successfully dispersed within bacterial cellulose (BC) substrate as bending anode with large loading mass for flexible supercapacitor. By virtue of its favorable architecture, this composite electrode exhibits a remarkable areal capacitance of 3322 mF cm<jats:sup>−2</jats:sup> at 2 mA cm<jats:sup>−2</jats:sup>, outstanding cycle performance (94.7% capacitance retention after 6000 cycles), and excellent mechanical strength (68.7 MPa). To push the energy density of flexible supercapacitors, the optimized asymmetric supercapacitor using Mn<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub>/GN/BC as positive electrode and Ti‐doped FeOOH QD/GN/BC as negative electrode can be cycled reversibly in the operating voltage range of 0–1.8 V and displays ultrahigh areal energy density of 0.541 mWh cm<jats:sup>−2</jats:sup>, ultrahigh volumetric energy density of 9.02 mWh cm<jats:sup>−3</jats:sup>, reasonable cycling performance (9.4% decay in specific capacitance after 5000 cycles), and good capacitive retention at bending state.</jats:p>

Eric Liese

Volume 4: Cycle Innovations; Industrial and Cogeneration; Manufacturing Materials and Metallurgy; Marine • 2009

<jats:p>This paper examines the arrangement of a solid oxide fuel cell (SOFC) within a coal gasification cycle, this combination generally being called an integrated gasification fuel cell cycle (IGFC). This work relies on a previous study performed by the National Energy Technology Laboratory (NETL) that details thermodynamic simulations of IGCC systems and considers various gasifier types and includes cases for 90% CO2 capture [1]. All systems in this study assume a Conoco Philips gasifier and cold gas clean up conditions for the coal gasification system (Cases 3 and 4 in the NETL IGCC report). Four system arrangements, cases, are examined. Cases 1 and 2 remove the CO2 after the SOFC anode. Case 3 assumes steam addition, a water-gas-shift (WGS) catalyst and a Selexol process to remove the CO2 in the gas cleanup section, sending a hydrogen-rich gas to the fuel cell anode. Case 4 assumes Selexol in the cold-gas cleanup section as in Case 3; however, there is no steam addition and the WGS takes places in the SOFC, and after the anode. Results demonstrate significant efficiency advantages compared to IGCC with CO2 capture. The hydrogen-rich case (Case 3) has better net electric efficiency compared to typical post-anode CO2 capture cases (Cases 1 and 2), with a simpler arrangement and similar SOFC area. Case 4 gives an efficiency similar to Case 3, but at a lower SOFC power density, or a lower efficiency at the same power density. Carbon deposition concerns are also discussed.</jats:p>

Shailesh Kumar Jadhav, Reena Meshram

International Journal of Renewable Energy Development • 2017

<jats:p>Microbial fuel cells (MFCs) are the electrochemical systems that harness the electricity production capacity of certain microbes from the reduction of biodegradable compounds. The present study aimed to develop mediator-less MFC without using expensive proton exchange membrane. In the present study, a triplicate of dual-chamber, mediator-less MFCs was operated with two local rice based industrial wastewater to explore the potential of this wastewater as a fuel option in these electrochemical systems. 30 combinations of 6 electrodes viz. Carbon (14 cm × 1.5 cm), Zn (14.9 cm × 4.9 cm), Cu (14.9 cm × 4.9 cm), Sn (14.1cm × 4.5cm), Fe (14cm × 4cm) and Al (14cm × 4.5 cm) were evaluated for each of the wastewater samples. Zn-C as anode-cathode combination produced a maximum voltage that was 1.084±0.016V and 1.086±0.028 and current of 1.777±0.115mA and 1.503±0.120 for KRM and SSR, respectively. In the present study, thick biofilm has been observed growing in MFC anode. Total 14 bacterial isolates growing in anode were obtained from two of the wastewater. The dual chambered, membrane-less and mediator-less MFCs were employed successfully to improve the economic feasibility of these electrochemical systems to generate bioelectricity and wastewater treatment simultaneously.Keywords: Membrane-less, Microbial Fuel Cells, Biofilm, Wastewater, Electrogenic.Article History: Received June 25th 2016; Received in revised form Dec 15th 2016; Accepted January 5th 2017; Available onlineHow to Cite This Article: Reena, M. and Jadhav, S. K. (2017) Bioelectricity production and Comparative Evaluation of Electrode Materials in Microbial Fuel Cells using Indigenous Anode-reducing Bacterial Community from Wastewater of Rice-based Industries. International Journal of Renewable Energy Develeopment, 6(1), 83-92.http://dx.doi.org/10.14710/ijred.6.1.83-92  </jats:p>

Yi-cheng Wu, Hong-jie Wu, Hai-yan Fu et al.

Environmental Engineering Research • 0

<jats:p>Sediment microbial fuel cells (SMFCs) are attractive devices to in situ power environmental monitoring sensors and bioremediate contaminated soils/sediments. Burial depth of the anode was verified to affect the performance of SMFCs. The present research evaluated the differences in microbial community structure of anodic biofilms located at different depth. It was demonstrated that both microbial diversity and community structure of anodic biofilms were influenced by the depth of anode location. Microbial diversity decreased with increased anodic depth. The number of the operational taxonomic units (OTUs) was determined as 1438 at the anode depth of 5 cm, which reduced to 1275 and 1005 at 10 cm and 15 cm, respectively. Cluster analysis revealed that microbial communities of 5 cm and 10 cm were clustered together, separated from the original sediment and 15 cm. Proteobacteria was the predominant phylum in all samples, followed by Bacteroidetes and Firmicutes. Beta-and Gamma-proteobacteria were the most abundant classes. A total of 23 OTUs showed high identity to 16S rRNA gene of exoelectrogens such as Geobacter and Pseudomonas. The present results provided insights into the effects of anode depth on the performance of SMFC from the perspectives of microbial community structure.</jats:p>

Pei Fu, Min Zeng, Qiuwang Wang

Volume 6B: Energy • 2016

<jats:p>For anode-supported planar solid oxide fuel cells (SOFCs), the thick anode support layer (ASL) prevents the supply of fuel gas to the anode functional layer (AFL) where the electrochemical reactions take place. Shortage of the fuel gas at the active region results in concentration polarization. SOFC designs with porosity gradient anode may improve the cell performance. In order to investigate the effect of the porosity distributions on mass transfer characteristics of SOFC, a three dimensional half-cell model is developed based on the computational fluid dynamics (CFD) method. The numerical model solves continuity equation, conservation of momentum, multi-component mass transfer and electrochemical reaction. According to the numerical results, a SOFC design with a higher porosity gradient anode could effectively enhance mass transport of the fuel gas in the AFLs, which would lead to the reduction of polarization loss. It is also found that high porosity gradient among the anode layers could improve the H2 concentration gradient in the porous anode, which is beneficial to facilitate diffusion of the fuel gas in the porous anode. Concentration overpotentials of the SOFC decrease with the increase of the porosity gradient, especially for the low inlet H2 molar fraction. These findings indicate that the comprehensive performance of SOFC can be effectively improved by employing a high porosity gradient anode.</jats:p>

Tianyun Zhang, Fujuan Wang, Liang Yang et al.

New Journal of Chemistry • 0

<p>Bacterial cellulose-derived cathode and anode with similar carbon microstructure are well match in kinetic for high energy density sodium-ion capacitor.</p>

Fujuan Wang, Xiaohong Shi, Junlei Zhang et al.

Nanoscale • 0

<jats:p>A carbon anode is prepared from polymer-blended bacterial cellulose by a mild heat-treatment process, and possesses widened interlayer distance, enhanced Na<jats:sup>+</jats:sup> diffusion rate, and improved diffusion-controlled capacity.</jats:p>

Henry Fonda Aritonang, Vanda Selvana Kamu, Ciptati Ciptati et al.

Bulletin of Chemical Reaction Engineering &amp; Catalysis • 2017

<jats:p>Highly dispersed platinum (Pt) nanoparticles / multiwalled carbon nanotubes (MWCNTs) on bacterial cellulose (BC) as anode catalysts for proton exchange membrane fuel cells (PEMFC) were prepared with various precursors and their electro-catalytic activities towards hydrogen oxidation at 70 oC under non-humidified conditions. The composite was prepared by deposition of Pt nanoparticles and MWCNTs on BC gel by impregnation method using a water solution of metal precursors and MWCNTs followed by reducing reaction using a hydrogen gas. The composite was characterized by using TEM (transmission electron microscopy), EDS (energy dispersive spectroscopy), and XRD (X-ray diffractometry) techniques. TEM images and XRD patterns both lead to the observation of spherical metallic Pt nanoparticles with mean diameter of 3-11 nm well impregnated into the BC fibrils. Preliminary tests on a single cell indicate that renewable BC is a good prospect to be explored as a membrane in fuel cell field. </jats:p>

Irina Amar Dubrovin, Lea Ouaknin Hirsch, Abhishiktha Chiliveru et al.

Microorganisms • 0

<jats:p>One of the main barriers to MEC applicability is the bacterial anode. Usually, the bacterial anode contains non-exoelectrogenic bacteria that act as a physical barrier by settling on the anode surface and displacing the exoelectrogenic microorganisms. Those non-exoelectrogens can also compete with exoelectrogenic microorganisms for nutrients and reduce hydrogen production. In this study, the bacterial anode was encapsulated by a dialysis bag including suspended graphite particles to improve current transfer from the bacteria to the anode material. An anode encapsulated in a dialysis bag without graphite particles, and a bare anode, were used as controls. The MEC with the graphite-dialysis-bag anode was fed with artificial wastewater, leading to a current density, hydrogen production rate, and areal capacitance of 2.73 A·m−2, 134.13 F·m−2, and 7.6 × 10−2 m3·m−3·d−1, respectively. These were highest when compared to the MECs based on the dialysis-bag anode and bare anode (1.73 and 0.33 A·m−2, 82.50 and 13.75 F·m−2, 4.2 × 10−2 and 5.2 × 10−3 m3·m−3·d−1, respectively). The electrochemical impedance spectroscopy of the modified graphite-dialysis-bag anode showed the lowest charge transfer resistance of 35 Ω. The COD removal results on the 25th day were higher when the MEC based on the graphite-dialysis-bag anode was fed with Geobacter medium (53%) than when it was fed with artificial wastewater (40%). The coulombic efficiency of the MEC based on the graphite-dialysis-bag anode was 12% when was fed with Geobacter medium and 15% when was fed with artificial wastewater.</jats:p>

Agathe Paitier, Naoufel Haddour, Chantal Gondran et al.

Molecules • 0

<jats:p>Low electrical conductivity of carbon materials is a source of potential loss for large carbonaceous electrode surfaces of MFCs due to the long distance traveled by electrons to the collector. In this paper, different configurations of titanium current collectors were used to connect large surfaces of carbon cloth anodes. The current collectors had different distances and contact areas to the anode. For the same anode surface (490 cm2), increasing the contact area from 28 cm2 to 70 cm2 enhanced power output from 58 mW·m−2 to 107 mW·m−2. For the same contact area (28 cm2), decreasing the maximal distance of current collectors to anodes from 16.5 cm to 7.75 cm slightly increased power output from 50 mW·m−2 to 58 mW·m−2. Molecular biology characterization (qPCR and 16S rRNA gene sequencing) of anodic bacterial communities indicated that the Geobacter number was not correlated with power. Moreover, Geobacter and Desulfuromonas abundance increased with the drop in potential on the anode and with the presence of fermentative microorganisms. Electrochemical impedance spectroscopy (EIS) showed that biofilm resistance decreased with the abundance of electroactive bacteria. All these results showed that the electrical gradient arising from collectors shapes microbial communities. Consequently, current collectors influence the performance of carbon-based anodes for full-scale MFC applications.</jats:p>

Huiqiang Liu, Wen Lei, Zeji Zhu et al.

ChemistrySelect • 2023

<jats:title>Abstract</jats:title><jats:p>Constructing peculiar carbon‐based networks built from hybrid structures has been considered as an effective approach to establish a superior scaffold for immobilization of nanoparticles. Herein, we demonstrate a facile and green approach to prepare cobalt oxides (CoO<jats:sub>x</jats:sub>)‐based anode, which is realized by rationally exploiting unique properties of carbonized bacterial cellulose (CBC) and graphene (GN). The unique configuration of GN/CoO<jats:sub>x</jats:sub>/CBC composite fully enables utilization of the synergistic effects from both three‐dimensional nanofibrous network and two‐dimensional “flexible confinement” function. Benefiting from their intriguing structural features, the synthesized composite is directly used as electrode for lithium‐ion batteries (LIBs), and achieves superior flexibility and reliability, enhanced energy/power density and outstanding cycling stability.</jats:p>

Alexiane Godain, Naoufel Haddour, Pascal Fongarland et al.

Catalysts • 0

<jats:p>This study investigated the effect of external resistance (Rext) on the dynamic evolution of microbial communities in anodic biofilms of single-chamber microbial fuel cells fueled with acetate and inoculated with municipal wastewater. Anodic biofilms developed under different Rext (0, 330 and 1000 ohms, and open circuit condition) were characterized as a function of time during two weeks of growth using 16S rRNA gene sequencing, cyclic voltammetry (CV) and fluorescence microscopy. The results showed a drastic difference in power output of MFCs operated with an open circuit and those operated with Rext from 0 to 1000 ohms. Two steps during the bacterial community development of the anodic biofilms were identified. During the first four days, nonspecific electroactive bacteria (non-specific EAB), dominated by Pseudomonas, Acinetobacter, and Comamonas, grew fast whatever the value of Rext. During the second step, specific EAB, dominated by Geobacter and Desulfuromonas, took over and increased over time, except in open circuit MFCs. The relative abundance of specific EAB decreased with increasing Rext. In addition, the richness and diversity of the microbial community in the anodic biofilms decreased with decreasing Rext. These results help one to understand the bacterial competition during biofilm formation and suggest that an inhibition of the attachment of non-specific electroactive bacteria to the anode surface during the first step of biofilm formation should improve electricity production.</jats:p>

Mohamed Mahmoud, Prathap Parameswaran, César I. Torres et al.

Biotechnology and Bioengineering • 2017

<jats:title>ABSTRACT</jats:title><jats:sec><jats:label /><jats:p>When anode‐respiring bacteria (ARB) respire electrons to an anode in microbial electrochemical cells (MXCs), they harvest only a small amount of free energy. This means that ARB must have a high substrate‐oxidation rate coupled with a high ratio of electrons used for respiration compared to total electrons removed by substrate utilization. It also means that they are especially susceptible to inhibition that slows anode respiration or lowers their biomass yield. Using several electrochemical techniques, we show that a relatively high total ammonium‐nitrogen (TAN) concentration (2.2 g TAN/L) induced significant stress on the ARB biofilms, lowering their true yield and forcing the ARB to boost the ratio of electrons respired per electrons consumed from the substrate. In particular, a higher respiration rate, measured as current density (<jats:italic>j</jats:italic>), was associated with slower growth and a lower net yield, compared to an ARB biofilm grown with a lower ammonium concentration (0.2 g TAN/L). Further increases in influent TAN (to 3 and then to 4.4 g TAN/L) caused nearly complete inhibition of anode respiration. However, the ARB could recover from high‐TAN inhibition after a shift of the MXC's feed to 0.2 g TAN/L. In summary, ARB biofilms were inhibited by a high TAN concentration, but could divert more electron flow toward anode respiration with modest inhibition and recover when severe inhibition was relieved. Biotechnol. Bioeng. 2017;114: 1151–1159. © 2017 Wiley Periodicals, Inc.</jats:p></jats:sec>

Anil N. Ghadge, Makarand M. Ghangrekar, Keith Scott

Journal of Renewable and Sustainable Energy • 2016

<jats:p>During scale-up of microbial fuel cell (MFC), a proportional increment in power does not usually occur determining the importance of maximum possible anode chamber volume (Van) to exploit electrogenesis and achieve maximum energy recovery. A systematic approach is proposed for determining the optimal single anode chamber volume and the minimum anode surface area (Aan) of an MFC. The optimal anode chamber volume was estimated based on the substrate required to produce a defined maximum current that is likely to be produced from the basic electromotive force equation. The Aan was obtained by considering the area required for biofilm formation, the substrate utilization rate by electrogens, the MFC polarization curve, charge transfer kinetics and mass transport overpotential. Based on the theoretical bio-electrochemical considerations, the maximum Van and minimum Aan required for each anode chamber are proposed for electrogenesis to dominate. A single Van of a few litres will only be optimal for treating wastewater. With wastewater of chemical oxygen demand (COD) of 5 g l−1 and considering a Coulombic efficiency and a COD removal of 80% each, a Van of 2.02 l is optimum for a single anode chamber to produce a current up to 750 mA; which is the maximum possible current estimated from electromotive force equation. Any additional volume provided will leave the substrate unused by electrogens and encourage methanogenesis. Adopting this volume for each anode chamber in a MFC stack is recommended for treating wastewater under the assumptions of the analysis. Charge transfer kinetics dominate the minimum Aan required, which satisfies the area required for biofilm formation, MFC polarization, and mass transfer. The minimum Aan should be provided in a MFC to ensure the dominance of electrogenesis.</jats:p>

Dawid Nosek, Piotr Jachimowicz, Agnieszka Cydzik-Kwiatkowska

Energies • 0

<jats:p>Sustainable production of electricity from renewable sources by microorganisms is considered an attractive alternative to energy production from fossil fuels. In recent years, research on microbial fuel cells (MFCs) technology for electricity production has increased. However, there are problems with up-scaling MFCs due to the fairly low power output and high operational costs. One of the approaches to improving energy generation in MFCs is by modifying the existing anode materials to provide more electrochemically active sites and improve the adhesion of microorganisms. The aim of this review is to present the effect of anode modification with carbon compounds, metallic nanomaterials, and polymers and the effect that these modifications have on the structure of the microbiological community inhabiting the anode surface. This review summarizes the advantages and disadvantages of individual materials as well as possibilities for using them for environmentally friendly production of electricity in MFCs.</jats:p>

Keren Yanuka-Golub, Vadim Dubinsky, Elisa Korenblum et al.

• 0

<jats:title>Abstract</jats:title><jats:p>Microbial fuel cells (MFCs) are devices that can generate energy while aiding biodegradation of waste through the activity of an electroactive mixed biofilm. Metabolic cooperation is considered essential for MFCs’ efficiency, especially during early-anode colonization. Yet, the specific ecological processes that drive the assembly of an optimized anode-attached community remain unknown. Here, we show, using 16S rRNA gene amplicon and shotgun metagenomic sequencing that bioaugmentation of the anode surface with an electroactive consortium originating from a well-established anodic biofilm, dominated by different<jats:italic>Desulfuromonas</jats:italic>strains, resulted in an extremely rapid voltage generation (reaching maximal voltage within several hours). This was in sharp contrast to the highly stochastic and slower biofilm assembly that occurred when the anode-surface was not augmented. By comparing two inoculation media, wastewater and filtered wastewater, we were able to illustrate two different "source-communities" for newly arriving species that with time colonized the anode surface in a different manner and resulted in dramatically different community assembly processes. Remarkably, an efficient anode colonization process was obtained only if unfiltered wastewater was added, leading to a near-complete replacement of the bioaugmented community by<jats:italic>Geobacter lovleyi</jats:italic>. We propose that anode bioaugmentation reduced stochasticity by creating available niches that were quickly occupied by specific newly-arriving species that positively supported the fast establishment of a highly-functional anode biofilm.</jats:p>

Matteo Grattieri, Kevin Beaver, Erin M. Gaffney et al.

Chemical Communications • 2020

Photo-bioelectrocatalysis combines the natural and highly sophisticated process of photosynthesis in biological entities with an abiotic electrode surface, to perform semi-artificial photosynthesis. However, challenges must be overcome, from the establishment and understanding of the photoexcited electron harvesting process at the electrode to the electrochemical characterization of these biotic/abiotic systems, and their subsequent tuning for enhancing energy generation (chemical and/or electrical). This Feature Article discusses the various approaches utilized to tackle these challenges, particularly focusing on powerful multi-disciplinary approaches for understanding and improving photo-bioelectrocatalysis. Among them is the combination of experimental evidence and quantum mechanical calculations, the use of bioinformatics to understand photo-bioelectrocatalysis at a metabolic level, or bioengineering to improve and facilitate photo-bioelectrocatalysis. Key aspects for the future development of photo-bioelectrocatalysis are presented alongside future research needs and promising applications of semi-artificial photosynthesis.

M. Aarthy, T. Rajesh, M. Thirunavoukkarasu

Journal of Chemical Technology &amp; Biotechnology • 2020

Rapid urbanization and industrialization has led to the indiscriminate discharge of heavy metals into the environment. Hexavalent chromium (Cr(VI)), a lethal, carcinogenic and genotoxic heavy metal frequently found in industrial effluent, poses a serious threat to human health. On the other hand, there is a global energy crisis prevalent owing to the scarcity of resources and huge energy demand. An emerging innovative technology which utilizes the biocatalytic activity of microbes for electron production and offers a dual solution for simultaneous reduction of Cr(VI) and generation of bioelectricity is the microbial fuel cell (MFC). The success of the MFC depends on variables such as cell configuration, pH, electrode materials, effect of microbial communities and operational conditions. This review provides a critical insight on the developments in the field of MFCs with abiotic and biotic cathodes, integrated systems, plant‐ and soil‐based designs for treatment of Cr(VI)‐laden effluent and sustainable energy recovery. © 2019 Society of Chemical Industry

Jian Liu, Jie Ma, Congwu He et al.

New Phytologist • 2013

The stresses acting on plants that are alleviated by silicon (Si) range from biotic to abiotic stresses, such as heavy metal toxicity. However, the mechanism of stress alleviation by Si at the single-cell level is poorly understood. We cultivated suspended rice (Oryza sativa) cells and protoplasts and investigated them using a combination of plant nutritional and physical techniques including inductively coupled plasma mass spectrometry (ICP-MS), the scanning ion-selective electrode technique (SIET) and X-ray photoelectron spectroscopy (XPS). We found that most Si accumulated in the cell walls in a wall-bound organosilicon compound. Total cadmium (Cd) concentrations in protoplasts from Si-accumulating (+Si) cells were significantly reduced at moderate concentrations of Cd in the culture medium compared with those from Si-limiting (-Si) cells. In situ measurement of cellular fluxes of the cadmium ion (Cd(2+) ) in suspension cells and root cells of rice exposed to Cd(2+) and/or Si treatments showed that +Si cells significantly inhibited the net Cd(2+) influx, compared with that in -Si cells. Furthermore, a net negative charge (charge density) within the +Si cell walls could be neutralized by an increase in the Cd(2+) concentration in the measuring solution. A mechanism of co-deposition of Si and Cd in the cell walls via a [Si-wall matrix]Cd co-complexation may explain the inhibition of Cd ion uptake, and may offer a plausible explanation for the in vivo detoxification of Cd in rice.

N. S. Weliwatte, Matteo Grattieri, S. Minteer

Photochemical &amp; Photobiological Sciences • 2021

Photobioelectrocatalysis has recently attracted particular research interest owing to the possibility to achieve sunlight-driven biosynthesis, biosensing, power generation, and other niche applications. However, physiological incompatibilities between biohybrid components lead to poor electrical contact at the biotic-biotic and biotic-abiotic interfaces. Establishing an electrochemical communication between these different interfaces, particularly the biocatalyst-electrode interface, is critical for the performance of the photobioelectrocatalytic system. While different artificial redox mediating approaches spanning across interdisciplinary research fields have been developed in order to electrically wire biohybrid components during bioelectrocatalysis, a systematic understanding on physicochemical modulation of artificial redox mediators is further required. Herein, we review and discuss the use of diffusible redox mediators and redox polymer-based approaches in artificial redox-mediating systems, with a focus on photobioelectrocatalysis. The future possibilities of artificial redox mediator system designs are also discussed within the purview of present needs and existing research breadth.

Giada Bedendi, L. D. de Moura Torquato, Sophie Webb et al.

ACS Measurement Science Au • 2022

The coupling of enzymes and/or intact bacteria with electrodes has been vastly investigated due to the wide range of existing applications. These span from biomedical and biosensing to energy production purposes and bioelectrosynthesis, whether for theoretical research or pure applied industrial processes. Both enzymes and bacteria offer a potential biotechnological alternative to noble/rare metal-dependent catalytic processes. However, when developing these biohybrid electrochemical systems, it is of the utmost importance to investigate how the approaches utilized to couple biocatalysts and electrodes influence the resulting bioelectrocatalytic response. Accordingly, this tutorial review starts by recalling some basic principles and applications of bioelectrochemistry, presenting the electrode and/or biocatalyst modifications that facilitate the interaction between the biotic and abiotic components of bioelectrochemical systems. Focus is then directed toward the methods used to evaluate the effectiveness of enzyme/bacteria–electrode interaction and the insights that they provide. The basic concepts of electrochemical methods widely employed in enzymatic and microbial electrochemistry, such as amperometry and voltammetry, are initially presented to later focus on various complementary methods such as spectroelectrochemistry, fluorescence spectroscopy and microscopy, and surface analytical/characterization techniques such as quartz crystal microbalance and atomic force microscopy. The tutorial review is thus aimed at students and graduate students approaching the field of enzymatic and microbial electrochemistry, while also providing a critical and up-to-date reference for senior researchers working in the field.

Glenn Quek, Samantha R McCuskey, R. J. Vázquez et al.

Advanced Electronic Materials • 2023

Bioelectrochemical systems hold the promise of enabling sustainable microbial‐mediated energy interconversion between electrical and chemical energy. Herein, it is demonstrated how a single conjugated polymer can be used to enhance bidirectional extracellular electron transfer through forming self‐assembled coatings on individual cells. Specifically, the n‐type conjugated polyelectrolyte p(cNDI‐gT2) exhibits a reduction potential window between −0.1 and −0.8 V (vs Ag/AgCl), thereby driving thermodynamically favored electron transfer in both directions across the abiotic‐biotic interface that involves the outer membrane cytochromes and flavins of Shewanella oneidensis MR‐1. Electrochemical tests show that injection from an external electrode into Shewanella oneidensis MR‐1 is enabled at negative potentials (−0.6 V), while electron extraction is possible at positive potentials (0.2 V). Relative to controls, the biohybrid shows a sixfold increase in biocurrent generation and a 35‐fold increase in current uptake for the bioelectrosynthesis of succinate from fumarate. This demonstrated abiotic‐biotic synergy provides new strategies for designing multifunctional biohybrids.