Research Library

Weilu Yang, Hexing Han, Minghua Zhou et al.

RSC Advances · 2015

A novel continuous flow electrosorption driven by microbial fuel cells (MFCs) was developed for the first time to remove tetracycline, the second most commonly used antibiotic, from synthetic wastewater.

Vajihe Yousefi, Davod Mohebbi-Kalhori, Abdolreza Samimi et al.

International Journal of Hydrogen Energy · 2016

Remisha S R, Reshmi R, Sanmathi K R

International Journal of Advanced Research in Science, Communication and Technology · 2023

The contamination of industrial wastewater with heavy metals poses a severe environmental and public health concern. Traditional methods of heavy metal removal often prove costly and environmentally unsustainable. In this context, microbial strategies have emerged as a promising and eco-friendly approach for effective heavy metal remediation from industrial wastewater. Microorganisms, including bacteria, fungi, and algae, have developed various mechanisms to withstand and sequester heavy metals from their surroundings. This review explores the diverse microbial strategies employed in heavy metal removal, encompassing biosorption, bioaccumulation, bioprecipitation, and bioleaching. These strategies exploit microbial cell surfaces, extracellular polymeric substances, and intracellular compartments to immobilize, transform, or release heavy metals. Moreover, recent advancements in genetic engineering and biotechnology have enabled the development of tailored microbial strains with enhanced metal-removal capabilities. The application of these engineered microbes, as well as naturally occurring strains, in bioremediation processes is discussed. This review also delves into the factors influencing microbial metal removal efficiency, such as pH, temperature, metal concentration, and co-existing contaminants. Additionally, the potential drawbacks and limitations of microbial strategies, including biomass disposal and long-term performance, are addressed. As heavy metal pollution continues to be a pressing global issue, understanding and harnessing microbial strategies for heavy metal removal from industrial wastewater holds significant promise for sustainable and cost-effective remediation practices. Integrating microbial processes into existing treatment methods can offer innovative solutions to mitigate the environmental impact of heavy metal contamination, thereby safeguarding ecosystems and public health

Dong-Mei Piao, Young-Chae Song, Dong-Hoon Kim

Energies · 2018

This study demonstrated the enhancement of biogenic coal conversion to methane in a bioelectrochemical anaerobic reactor with polarized electrodes. The electrode with 1.0 V polarization increased the methane yield of coal to 52.5 mL/g lignite, which is the highest value reported to the best of our knowledge. The electrode with 2.0 V polarization shortened the adaptation time for methane production from coal, although the methane yield was slightly less than that of the 1.0 V electrode. After the methane production from coal in the bioelectrochemical reactor, the hydrolysis product, soluble organic residue, was still above 3600 mg chemical oxygen demand (COD)/L. The hydrolysis product has a substrate inhibition effect and inhibited further conversion of coal to methane. The dilution of the hydrolysis product mitigates the substrate inhibition to methane production, and a 5.7-fold dilution inhibited the methane conversion rate by 50%. An additional methane yield of 55.3 mL/g lignite was obtained when the hydrolysis product was diluted 10-fold in the anaerobic toxicity test. The biogenic conversion of coal to methane was significantly improved by the polarization of the electrode in the bioelectrochemical anaerobic reactor, and the dilution of the hydrolysis product further improved the methane yield.

Brittany Newell, Jose Garcia, Gary Krutz

Actuators · 2018

Dielectric electroactive polymer materials represent a distinct group of smart materials that are capable of converting between electrical and mechanical energy. This research focuses on the modeling and testing of an industrial grade fluoropolymer material for its feasibility as a dielectric elastomer electroactive polymer. Through this process, a novel chemical pre-strain method was tested, along with a one-step process for application of pre-strain and addition of an elastomer conductive layer. Modeled and experimental actuators produced approximately 1 mm displacements with 0.625 W of electrical power. The displacement of the actuators was characterized, and the effects of multiple parameters were modeled and analyzed.

Erin M. Gaffney, Olja Simoska, Shelley D. Minteer

Biosensors · 2021

Halophilic bacteria are remarkable organisms that have evolved strategies to survive in high saline concentrations. These bacteria offer many advances for microbial-based biotechnologies and are commonly used for industrial processes such as compatible solute synthesis, biofuel production, and other microbial processes that occur in high saline environments. Using halophilic bacteria in electrochemical systems offers enhanced stability and applications in extreme environments where common electroactive microorganisms would not survive. Incorporating halophilic bacteria into microbial fuel cells has become of particular interest for renewable energy generation and self-powered biosensing since many wastewaters can contain fluctuating and high saline concentrations. In this perspective, we highlight the evolutionary mechanisms of halophilic microorganisms, review their application in microbial electrochemical sensing, and offer future perspectives and directions in using halophilic electroactive microorganisms for high saline biosensing.

Arkadiy I. Garber, Kenneth H. Nealson, Nancy Merino

Frontiers in Microbiology · 2024

Multi-heme cytochromes (MHCs), together with accessory proteins like porins and periplasmic cytochromes, enable microbes to transport electrons between the cytoplasmic membrane and extracellular substrates (e.g., minerals, electrodes, other cells). Extracellular electron transfer (EET) has been described in multiple systems; yet, the broad phylogenetic and mechanistic diversity of these pathways is less clear. One commonality in EET-capable systems is the involvement of MHCs, in the form of porin-cytochrome complexes, pili-like cytochrome polymers, and lipid-anchored extracellular cytochromes. Here, we put forth MHCscan—a software tool for identifying MHCs and identifying potential EET capability. Using MHCscan, we scanned ~60,000 bacterial and 2,000 archaeal assemblies, and identify a diversity of MHCs, many of which represent enzymes with no known function, and many found within organisms not previously known to be electroactive. In total, our scan identified ~1,400 unique enzymes, each encoding more than 10 heme-binding motifs. In our analysis, we also find evidence for modularity and flexibility in MHC-dependent EET pathways, and suggest that MHCs may be far more common than previously recognized, with many facets yet to be discovered. We present MHCscan as a lightweight and user-friendly software tool that is freely available: https://github.com/Arkadiy-Garber/MHCscan .

Shan-Wei Li, Guo-Ping Sheng, Yuan-Yuan Cheng et al.

Scientific Reports · 2016

Abstract Although the capacity for electroactive bacteria to convert environmental metallic minerals and organic pollutants is well known, the role of the redox properties of microbial extracellular polymeric substances (EPS) in this process is poorly understood. In this work, the redox properties of EPS from two widely present electroactive bacterial strains ( Shewanella oneidensis and Pseudomonas putida ) were explored. Electrochemical analysis demonstrates that the EPS extracted from the two strains exhibited redox properties. Spectroelectrochemical and protein electrophoresis analyses indicate that the extracted EPS from S. oneidensis and P. putida contained heme-binding proteins, which were identified as the possible redox components in the EPS. The results of heme-mediated behavior of EPS may provide an insight into the important roles of EPS in electroactive bacteria to maximize their redox capability for biogeochemical cycling, environmental bioremediation and wastewater treatment.

Robin Bonné, Koen Wouters, Jamie J. M. Lustermans et al.

Frontiers in Microbiology · 2022

The global production of unrecycled electronic waste is extensively growing each year, urging the search for alternatives in biodegradable electronic materials. Electroactive bacteria and their nanowires have emerged as a new route toward electronic biological materials (e-biologics). Recent studies on electron transport in cable bacteria—filamentous, multicellular electroactive bacteria—showed centimeter long electron transport in an organized conductive fiber structure with high conductivities and remarkable intrinsic electrical properties. In this work we give a brief overview of the recent advances in biodegradable electronics with a focus on the use of biomaterials and electroactive bacteria, and with special attention for cable bacteria. We investigate the potential of cable bacteria in this field, as we compare the intrinsic electrical properties of cable bacteria to organic and inorganic electronic materials. Based on their intrinsic electrical properties, we show cable bacteria filaments to have great potential as for instance interconnects and transistor channels in a new generation of bioelectronics. Together with other biomaterials and electroactive bacteria they open electrifying routes toward a new generation of biodegradable electronics.

Min-Hua Cui, Dan Cui, Hyung-Sool Lee et al.

Scientific Reports · 2016

Abstract In this study, two modes of hybrid anaerobic digestion (AD) bioreactor with built-in BESs (electrodes installed in liquid phase (R1) and sludge phase (R2)) were tested for identifying the effect of electrodes position on azo dye wastewater treatment. Alizarin yellow R (AYR) was used as a model dye. Decolorization efficiency of R1 was 90.41 ± 6.20% at influent loading rate of 800 g-AYR/ m 3 ·d, which was 39% higher than that of R2. The contribution of bioelectrochemical reduction to AYR decolorization (16.23 ± 1.86% for R1 versus 22.24 ± 2.14% for R2) implied that although azo dye was mainly removed in sludge zone, BES further improved the effluent quality, especially for R1 where electrodes were installed in liquid phase. The microbial communities in the electrode biofilms (dominant by Enterobacter) and sludge (dominant by Enterococcus) were well distinguished in R1, but they were similar in R2. These results suggest that electrodes installed in liquid phase in the anaerobic hybrid system are more efficient than that in sludge phase for azo dye removal, which give great inspirations for the application of AD-BES hybrid process for various refractory wastewaters treatment.

Patricia M. Olmos Moya, Silvia Gutiérrez Granados, Fethi Bedioui et al.

Electroanalysis · 2020

Abstract An amperometric biosensor for the sensitive detection of superoxide was designed utilizing a drop‐coating approach for immobilizing the superoxide dismutase enzyme on Pt electrode modified with a thin layer of poly (3,4‐ethylenedioxythiophene) (PEDOT). The layer electrodeposited on Pt was characterized by cyclic voltammetry and atomic force microscopy (AFM). Then, drop‐coating procedure was chosen for the immobilization of superoxide dismutase (SOD), which was incorporated at the electrode surface using a solution containing SOD, glutaraldehyde and bovine serum albumin (optimized composition: SOD 0.1 % – BSA 2 % – GA 2.5 % .) This simple procedure allows forming a reproducible enzymatic biocomposite layer that allows optimal sensitivity and limit of detection for superoxide sensing. The synergistic effect integrates an effective conductivity and permselectivity attributed to the PEDOT layer, as well as the specificity and selectivity of SOD for the detection of superoxide. A high sensitivity (0.82±0.01 μA/μM) and a low detection limit of 11 nM were obtained, as well as good selectivity against main interfering biological compounds such as uric acid and ascorbic acid. Our results suggest that the biosensor could be used for the detection and quantification of in vitro and in vivo .

Andreea Madalina Pandele, Corina Andronescu, Adi Ghebaur et al.

Materials · 2018

A high number of studies support the use of mesoporous silica nanoparticles (MSN) as carriers for drug delivery systems due to its high biocompatibility both in vitro and in vivo, its large surface area, controlled pore size and, more than this, its good excretion capacity from the body. In this work we attempt to establish the optimal encapsulation parameters of benzalkonium chloride (BZC) into MSN and further study its drug release. The influence of different parameters towards the drug loading in MSN such as pH, contact time and temperature were considered. The adsorption mechanism of the drug has been determined by using the equilibrium data. The modification process was proved using several methods such as Fourier transform-infrared (FT-IR), ultraviolet-visible (UV-VIS), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). Since MSN shows a lower drug release amount due to the agglomeration tendency, in order to increase MSN dispersion and drug release amount from MSN, two common biocompatible and biodegradable polymers were used as polymer matrix in which the MSN-BZC can be dispersed. The drug release profile of the MSN-BZC and of the synthesized hybrid materials were studied both in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF). Polymer-MSN-BZC hybrid materials exhibit a higher drug release percent than the pure MSN-BZC when a higher dispersion is achieved. The dispersion of MSN into the hybrid materials was pointed out in scanning electron microscope (SEM) images. The release mechanism was determined using four mathematic models including first-order, Higuchi, Korsmeyer–Peppas and Weibull.

Miroslav Kvíčala, Michaela Štamborská, Jaromír Drápala

Applied Mechanics and Materials · 2015

This paper is dedicated to the development and optimization of the porous titanium materials suitable for biomedical usage in traumatology. Main aim of the presented research activities is focused on preparation of biocompatible titanium based materials with controlled porosity. It was found that titanium specimens with total porosity approximately 40 % revealed mechanical properties very similar to those of human cortical bone. Two-layer specimens with controlled porosity were prepared and tested by electron microscopy for post-sintering cracks. All tested specimens with controlled porosity were cracks free. Future works will include preparation of geometrically more complicated shapes, machining and in vitro cells proliferation testing.

Mohammad Luqman, Saeed Alqaed, Fahad Awjah Almehmadi et al.

Journal of Electroanalytical Chemistry · 2024

Yanuar Rohmat Aji Pradana, Firhan Ahmad Fanani, Aminnudin Aminnudin et al.

Key Engineering Materials · 2020

Subsequent processing through machining for biocompatible Zr-based BMG previously developed is needed in order to enlarge the material application, especially for medical devices. In this study the performance of CuCr tool on EDM process was investigated to cut biocompatible Zr-based BMG having low machinability nature. The experiment utilized volume loss technique to measure the TWR and consecutive SEM observation to reveal the tool wear mechanism of selected tool samples. The tool wear behavior was strongly characterized by the combination of discharge current and pulse-on time, where the larger TWR obtained by higher current and shorter pulse-on time. By SEM analysis, the irregular-shaped surface morphology with the presence of debris was observed on the tool wear region resulted by high discharge energy process. Additionally, the larger crater size, microvoids and numerous debris particles were also appeared on BMG workpiece surface machined using higher discharge energy.

Hindatu Yusuf, M. Suffian M. Annuar, Syed Mohammad Daniel Syed Mohamed et al.

Chemical Engineering Communications · 2019

Mohan Qin, Ibrahim M. Abu-Reesh, Zhen He

Water Research · 2016

Osmotic microbial fuel cells (OsMFCs) take advantages of synergy between forward osmosis (FO) and microbial fuel cells (MFCs) to accomplish wastewater treatment, current generation, and high-quality water extraction. As an FO based technology, OsMFCs also encounter reverse salt flux (RSF) that is the backward transport of salt ions across the FO membrane into the treated wastewater. This RSF can reduce water flux, contaminate the treated wastewater, and increase the operational expense, and thus must be properly addressed before any possible applications. In this study, we aimed to understand the effects of current generation and electrolyte pH on RSF in an OsMFC. It was found that electricity generation could greatly inhibit RSF, which decreased from 16.3 ± 2.8 to 3.9 ± 0.7 gMH when the total Coulomb production increased from 0 to 311 C. The OsMFC exhibited 45.9 ± 28.4% lower RSF at the catholyte pH of 3 than that at pH 11 when 40 Ω external resistance was connected. The amount of sodium ions transported across the FO membrane was 18.3-40.7% more than that of chloride ions. Ion transport was accomplished via diffusion and electrically-driven migration, and the theoretical analysis showed that the inhibited electrically-driven migration should be responsible for the reduced RSF. These findings are potentially important to control and reduce RSF in OsMFCs or other osmotic-driven processes.

Harsha Nagar, N. Badhrachalam, V.V. Basava Rao et al.

Materials Chemistry and Physics · 2019

R. M. Alonso, M. I. San-Martín, A. Sotres et al.

Scientific Reports · 2017

Abstract This study seeks to assess the impact that the anodic electrodeposition of graphene oxide (GO) has on the start-up process and on the development of microbial communities on the anode of BESs. The GO electrodeposited electrodes were characterised in abiotic conditions to verify the extent of the modification and were then transferred to a bioelectrochemical reactor. Results showed that the modified electrode allowed for a reduced start-up time compared to the control electrode. After three months, high throughput sequencing was performed, revealing that electrochemically reduced graphene oxide acts as a selective agent toward exoelectrogenic bacteria as Geobacter . Overall, this study shows that GO modified electrodes enhance biofilm build up in BES.

Vijay Jaswal, Rajesh Banu J, Yogalakshmi K. N.

SSRN Electronic Journal · 2022

Nano-bedecking of electrode with nanoparticles is an effective method to improve power generation of microbial fuel cells (MFCs). In this study, different concentrations (0.25 mg cm -2 , 0.50 mg cm -2 , 0.75 mg cm -2 and 1.0 mg cm -2 ) of TiO 2 nanoparticles of size 10-25 nm were overlaid on the carbon cloth (CC) using spray pyrolysis technique and used as catalytic cathode in a dual-chambered microbial fuel cell treating distillery wastewater. Results evidenced that TiO 2 nanoparticles modified cathode increased the power generation and recorded a highest power and current density of 162.5 ± 2 mW m -2 and 1.4 ± 0.005 A m -2 , respectively. Carbon cloth coated with 0.50 mg cm -2 TiO 2 nanoparticles showed 2.8 and 7.3 times higher current and power density as compared to uncoated cathode. MFC operated at a hydraulic retention time (HRT) and organic loading rate (OLR) of 72 h and 59.2 g COD L -1 d -1 showed a maximum chemical oxygen demand (COD) removal of 72.3% which was 15.3% higher than the control MFC. Likewise, the coulombic efficiency of control and modified MFC was 33% and 44%, respectively. The maximum NO 3 - - N, NO 2 - - N and NH 4 + - N removal efficiency of 77.3%, 49.9% and 59.4% were observed for TiO 2 nanoparticles modified electrode which was 19.3%, 11.4% and 10.5% higher than control. TiO 2 modified cathode was effective in enhancing the bioelectricity generation in MFCs.

Sevi Murugavel

ECS Meeting Abstracts · 2023

The development of new and novel electrode materials for energy storage devices has become the intensive research by the materials science community because of its importance in the portable electronic devices, hybrid electric vehicles and many other applications. Since the discovery by Goodenough and his co-workers on the electrochemical behavior of olivine LiFePO 4 (LFP), different theoretical and experimental investigations have been undertaken to optimize it as cathode material in lithium-ion batteries and trying to understand the charge/discharge mechanism. Despite having many fascinating electrochemical properties, the main drawback of LFP lies with its low gravimetric density and poor electrical conductivity (both electronic and ionic) which limits the lithium intercalation/deintercalation rates, and hence the practical specific capacity. Therefore, it becomes necessary to gain the fundamental understanding of electronic structure of the LFP system by adopting appropriate experimental technique. We exploit the combined Mössbauer and X-ray absorption spectroscopy to unravel the electronic structure and local site symmetry of Fe in olivine structured LFP with different crystallite sizes (CS). The lattice parameters are found to contract with decrease in CS monotonously, whereas the electronic structural parameters exhibit two different regions with threshold anomaly around ≈30 nm CS. The 57 Fe Mössbauer studies reveal the coexistence of Fe 2+ and Fe 3+ sites and their relative concentration are mainly determined by the CS, which provides the comprehensive insight into the electronic structure of LFP at mesoscopic level. The soft X-ray absorption unravels unequivocally the valance states of Fe 3d electrons in the proximity of Fermi level, which are prone to the local lattice distortion. An obtained spectra fingerprint the effect of CS supplying rich information on valence state of iron, lithium-ion vacancy concentration, covalency and crystal field. The unique structural and electronic properties of the LFP are closely interlinked with changes in the bonding character, which shows the strong dependency on the CS. The evolution of the 3d states is in overall agreement with the local lattice distortion and provides the origin of the size effects on the electronic structure olivine phosphate and other transition metal ion containing materials. We observe polaronic conductivity enhancement of approximately two orders of magnitude at the nanoscale level as compared with its bulk counterpart. The volumetric changes with respect to crystallite size are related to the compressive strain resulting into the improvement in the electronic diffusivity. The nano-crystalline LFP with better kinetics will open the new avenue for its usage as cathode material in rechargeable batteries.

Carolina del Real Mata, Roozbeh Siavash Moakhar, Sara Mahshid

ECS Meeting Abstracts · 2020

Hydrogen peroxide (H 2 O 2 ) acts as a critical second messenger in fundamental biological processes, which makes it a highly important target for direct detection in biological systems. Among various read-out techniques, photoelectrochemical (PEC) sensing offers a low limit of detection and high sensitivity. Here, a promising, non-enzymatic, sunlight-driven, simple photoelectrochemical (PEC) sensor for H 2 O 2 detection is presented. The electrode is based on a Si wafer, a thick ZnO spacer, a thin Au layer and a graphene layer on top. The fabrication was done through conventional e-beam evaporation deposition technique for the spacer and metal film. An additional layer of graphene was drop-casted on top. The latter provides highly conductive scaffolds to ease electron transport and to increase the electrode sensitivity. The morphological characteristics and optical properties were investigated via FESEM and UV-Vis spectroscopy, respectively. Additionally, the electrochemical characterization was conducted using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry. Direct detection of H 2 O 2 was studied via chronoamperometry method under simulated sunlight by using a three-electrode configuration in which stainless-steel served as both counter and reference electrodes and the fabricated electrode as the working electrode. The photo responses to gold and gold/graphene electrodes in a non-enzymatic and biocompatible PBS environment with a pH 7.2 were thoroughly investigated. The gold-graphene demonstrates boosted properties combining excellent photoelectroactivity and high sensitivity towards H 2 O 2 with a superb limit of detection of 1pM in a linear range of 1pM-100mM. Keywords : Hydrogen peroxide, gold, graphene, photoelectrochemical sensor

Takafumi Kato, Takuya Yoda, Naoki Yoshihara

Chemistry Letters · 2022

Abstract Biomass-derived carbon materials have attracted interest as metal-free electrode candidates for electrochemical reactions. Hydrocarbon formation (i.e., methane and ethane) using the electrochemical reduction of carbon dioxide (CO2ER) on as-synthesized sulfur (S) containing lignin derived carbon electrodes was demonstrated. The current efficiencies of hydrocarbon products by CO2ER were found to be dependent on the carbonized temperature and a thermal treatment scheme, resulting in different surface structures and chemical composition of S species.

Sandipam Srikanth, Yolanda Alvarez‐Gallego, Karolien Vanbroekhoven et al.

ChemPhysChem · 2017

Abstract The enzymatic electrosynthesis of formic acid from the reduction of carbon dioxide (CO 2 ) by using formate dehydrogenase (FDH) as a catalyst at the cathode in both its free and immobilized forms was studied in detail in a bioelectrochemical system (BES). The essential role of solubilizing CO 2 for its conversion was also studied by adding carbonic anhydrase (CA) to the FDH enzyme in both its free and immobilized forms. FDH alone in the free form showed large variation in the reduction current [(−6.2±3.9) A m −2 ], whereas the immobilized form showed less variation [(−3.8±0.5) A m −2 ] due to increased enzyme stability. The addition of CA with FDH increased the consumption of the current in both forms due to the fact that it allowed rapid dissolution of CO 2 , which made it available for the catalytic reaction with FDH. Remarkably, stable consumption of the current was observed throughout the operation if both CA and FDH were immobilized onto the electrode [(−3.9±0.2) A m −2 ]. Product formation by the immobilized enzyme was also continued for three repetitive cycles, which revealed the longevity of the enzyme after immobilization. The recyclability of NADH (NAD=nicotinamide adenine dinucleotide) was also clearly evidenced on the derivative voltammetric signature. Extension of this study for continuous and long‐term operation may reveal more possibilities for the rapid capture and conversion of CO 2 .

Nhlanganiso Ivan Madondo, Sudesh Rathilal, Babatunde Femi Bakare et al.

International Journal of Molecular Sciences · 2023

The interspecies electron transfer (IET) between microbes and archaea is the key to how the anaerobic digestion process performs. However, renewable energy technology that utilizes the application of a bioelectrochemical system together with anaerobic additives such as magnetite-nanoparticles can promote both direct interspecies electron transfer (DIET) as well as indirect interspecies electron transfer (IIET). This has several advantages, including higher removal of toxic pollutants present in municipal wastewater, higher biomass to renewable energy conversion, and greater electrochemical efficiencies. This review explores the synergistic influence of bioelectrochemical systems and anaerobic additives on the anaerobic digestion of complex substrates such as sewage sludge. The review discussions present the mechanisms and limitations of the conventional anaerobic digestion process. In addition, the applicability of additives in syntrophic, metabolic, catalytic, enzymatic, and cation exchange activities of the anaerobic digestion process are highlighted. The synergistic effect of bio-additives and operational factors of the bioelectrochemical system is explored. It is elucidated that a bioelectrochemical system coupled with nanomaterial additives can increase biogas–methane potential compared to anaerobic digestion. Therefore, the prospects of a bioelectrochemical system for wastewater require research attention.

Yilkal Dessie, Sisay Tadesse

Sensing and Bio-Sensing Research · 2022

Sweta Naik, Satya Eswari Jujjavarapu

Journal of Environmental Chemical Engineering · 2021

Soon Bee Quek, Liang Cheng, Ralf Cord-Ruwisch

Bioresource Technology · 2015

Assimilable organic carbon (AOC) is a key predictor for membrane biofouling in seawater desalination reverse osmosis (SWRO). Microbial fuel cells have been considered as biosensors for the detection of biodegradable organics. However, the presence of dissolved oxygen (DO) is known to completely suppress the signal production (i.e., current) of a typical MFC. This study describes AOC detection in normal oxygenated seawater by coupling an electrochemical cell for DO removal with a MFC-biosensor for AOC detection. The electrochemical deoxygenation for oxygen removal caused no interference in the AOC detection. A linear relationship (R(2)=0.991) between the AOC concentration and current production from the MFC biosensor was achieved. The coupling of an electrochemical cell with a MFC-biosensor can be effectively used as an online, rapid and inexpensive measure of AOC concentrations and hence as an indicator for biofouling potential of seawater.

Soon Bee Quek, Liang Cheng, Ralf Cord-Ruwisch

Water Research · 2015

The development of an assimilable organic carbon (AOC) detecting marine microbial fuel cell (MFC) biosensor inoculated with microorganisms from marine sediment was successful within 36 days. This established marine MFC was tested as an AOC biosensor and reproducible microbiologically produced electrical signals in response to defined acetate concentration were achieved. The dependency of the biosensor sensitivity on the potential of the electron-accepting electrode (anode) was investigated. A linear correlation (R(2) > 0.98) between electrochemical signals (change in anodic potential and peak current) and acetate concentration ranging from 0 to 150 μM (0-3600 μg/L of AOC) was achieved. However, the present biosensor indicated a different-linear relation at somewhat elevated acetate concentration ranging from 150 to 450 μM (3600-10,800 μg/L of AOC). This high concentration of acetate addition could be measured by coulombic measurement (cumulative charges) with a linear correlation. For the acetate concentration detected in this study, the sensor recovery time could be controlled within 100 min.

Adib Mahmoodi Nasrabadi, Mahdi Moghimi

International Journal of Hydrogen Energy · 2022

Mohammad Ranjbar, Mohammadreza Esmailbagi, Mahin Schaffie

Solid State Phenomena · 2017

The objective of this study is to improve the understanding of copper sulfides dissolution and to use this knowledge for optimization of process parameters for commercial application of electrochemical bioleaching of chalcopyrite concentrates in stirred bioreactors. From the results of this study, the importance of the oxidation reduction potential (ORP) on the catalytic interaction between chalcopyrite and pyrite can be pointed out as the main parameters for successful bioprocessing of chalcopyrite concentrates. Under these conditions, the optimization of the average particle size of feed (D80) and adjusting the ORP in the range between 400-450 mV are important criteria for increasing the electrochemical bioleaching rate of chalcopyrite concentrates. It seems that the main reason for the increased copper recovery could be the control and prevention of chalcopyrite passivation resulting from improved galvanic interaction between copper sulfide minerals, here especially chalcopyrite and pyrite in the selected ORP range and the right particle size distribution of feed. At optimum conditions, the copper extraction from chalcopyrite flotation concentrate during 7 days of continuous electrochemical bioleaching operations in stirred tanks was about 95%, which should be high enough to justify the process economically.

Huajun Feng, Xueqin Zhang, Kun Guo et al.

Applied and Environmental Microbiology · 2015

ABSTRACT Fed batch bioelectrochemical systems (BESs) based on electrical stimulation were used to treat p -fluoronitrobenzene ( p -FNB) wastewater at high salinities. At a NaCl concentration of 40 g/liter, p -FNB was removed 100% in 96 h in the BES, whereas in the biotic control (BC) (absence of current), p -FNB removal was only 10%. By increasing NaCl concentrations from 0 g/liter to 40 g/liter, defluorination efficiency decreased around 40% in the BES, and in the BC it was completely ceased. p -FNB was mineralized by 30% in the BES and hardly in the BC. Microorganisms were able to store 3.8 and 0.7 times more K + and Na + intracellularly in the BES than in the BC. Following the same trend, the ratio of protein to soluble polysaccharide increased from 3.1 to 7.8 as the NaCl increased from 0 to 40 g/liter. Both trends raise speculation that an electrical stimulation drives microbial preference toward K + and protein accumulation to tolerate salinity. These findings are in accordance with an enrichment of halophilic organisms in the BES. Halobacterium dominated in the BES by 56.8% at a NaCl concentration of 40 g/liter, while its abundance was found as low as 17.5% in the BC. These findings propose a new method of electrical stimulation to improve microbial salinity resistance.

Shu-Hui Liu, Kun-Yan Lee

Journal of Power Sources · 2021

Ademola Adekunle, Vijaya Raghavan, Boris Tartakovsky

Journal of Power Sources · 2017

Chaeho Im, Minsoo Kim, Jung Rae Kim et al.

Frontiers in Microbiology · 2024

Fossil resources must be replaced by renewable resources in production systems to mitigate green-house gas emissions and combat climate change. Electro-fermentation utilizes a bioelectrochemical system (BES) to valorize industrial and municipal waste. Current electro-fermentation research is mainly focused on microbial electrosynthesis using CO 2 for producing commodity chemicals and replacing petroleum-based infrastructures. However, slow production rates and low titers of metabolites during CO 2 -based microbial electrosynthesis impede its implementation to the real application in the near future. On the other hand, CO is a highly reactive gas and an abundant feedstock discharged from fossil fuel-based industry. Here, we investigated CO and CO 2 electro-fermentation, using a CO-enriched culture. Fresh cow fecal waste was enriched under an atmosphere of 50% CO and 20% CO 2 in N 2 using serial cultivation. The CO-enriched culture was dominated by Clostridium autoethanogenum (≥89%) and showed electro-activity in a BES reactor with CO 2 sparging. When 50% CO was included in the 20% CO 2 gas with 10 mA applied current, acetate and ethanol were produced up to 12.9 ± 2.7 mM and 2.7 ± 1.1 mM, respectively. The coulombic efficiency was estimated to 148% ± 8% without an electron mediator. At 25 mA, the culture showed faster initial growth and acetate production but no ethanol production, and only at 86% ± 4% coulombic efficiency. The maximum optical density (OD) of 10 mA and 25 mA reactors were 0.29 ± 0.07 and 0.41 ± 0.03, respectively, whereas it was 0.77 ± 0.19 without electric current. These results show that CO electro-fermentation at low current can be an alternative way of valorizing industrial waste gas using a bioelectrochemical system.

Jean Pierre Muhoza, Hongzhi Ma, Loissi Kalakodio et al.

International Journal of Waste Resources · 2017

Tekalign Tesfaye, Yohannes Shuka, Sisay Tadesse et al.

Scientific Reports · 2025

A microbial fuel cell (MFC) is a modern, environmentally friendly, and cost-effective energy conversion technology that utilizes renewable organic waste as fuel, converting stored chemical energy into usable bioelectricity in the presence of a biocatalyst. Despite advancements in MFC technology, several challenges remain in optimizing power production efficiency, particularly regarding anode materials and modifications. In this study, low-cost biosynthesized iron oxide nanoparticles (Fe 3 O 4 NPs) were coated with a polyaniline (PANI) conducting matrix to synthesize hybrid Fe 3 O 4 /PANI binary nanocomposites (NCs) as modified MFC anodes via an in-situ polymerization process. Characterization techniques, including UV-Vis, XRD, SEM, and FT-IR, revealed the successful synthesis of green-routed nano-scaled materials with altered optical properties after matrix coating, high crystallinity in the iron oxide phase, rougher surface morphology, and characteristic Fe-O peaks at 594 cm⁻ 1 . Additionally, the electrochemical behavior of the prepared nano-materials was characterized by cyclic voltammetry (CV), where low ΔEp values (0.473 V) for Fe 3 O 4 /PANI NCs indicated the presence of reversible charge transfer mechanisms at the electrode surface, reflecting a high rate of electron transfer. The synthesized nanocomposite was used to modify pencil graphite anodes to construct four single-chamber MFCs: bare pencil graphite anodes, pencil graphite anodes modified with Fe 3 O 4 , PANI, and Fe 3 O 4 /PANI nanocomposites. The maximum open circuit voltage (OCV) value was 645 ± 24.50 mV, with a high power output of 424.51 ± 6.86 mW/m 2 and current density of 2475.01 ± 1.23 mA m -2 produced by the Fe 3 O 4 /PANI NCs modified pencil graphite electrode, which is more than six times the efficiency in terms of power density compared to the unmodified pencil graphite electrode (PGE). These results demonstrate that the synthesized nanocomposite plays an effective and value-added role in modifying traditional carbon anode electrodes within an MFC energy conversion device system.

Sadia Sikder, Md. Mostafizur Rahman

Case Studies in Chemical and Environmental Engineering · 2023

Kyle S. Jiang, Betar M. Gallant

ECS Meeting Abstracts · 2023

The lithium (Li) metal anode holds great promise for high energy-density rechargeable batteries due to its high gravimetric capacity (3860 mAh/g), an order of magnitude larger than graphite at a similar electrochemical potential (-3.040 V vs SHE for Li). However, limited Coulombic efficiency (CE), caused by the thermodynamic instability of conventional Li-ion electrolyte solvents and salts with Li that leads to unstable solid-electrolyte interphase (SEI) during repeated plating and stripping, has hindered the commercialization of Li metal batteries. Research efforts have focused on tuning the electrolyte composition to promote a stable SEI that simultaneously blocks continuous side reactions and electronic conductivity while facilitating Li + transport [1], with coin cells being by far the most preferred form factor for evaluating these electrolyte designs. Coin cells enable accessible and rapid testing of diverse electrolyte compositions. Their preparation requires no specialized equipment beyond an inert chemical environment, a crimping mechanism to seal the cell, and modest quantities of Li metal (~50 - 100 μm thickness) and electrolyte (~50 - 100 μL volume) [2]. Despite these attractive features, the procedures for preparing and techniques for measuring CE in coin cells are not fully standardized. In this presentation, we examine the impact on measured CE from preparation and testing procedures, including the internal coin cell stack consisting of components such as the electrodes, current collectors / spacers, and separators, and the cycling protocol. While the cycling protocol and cycling capacity are known to affect capacity loss mechanisms in Li metal batteries [3], we show that variances in CE can additionally be attributed to specific details of cell preparation. In particular, the working electrode area and stack thickness affect the pressure magnitude and uniformity inside the cell. We demonstrate that standardizing the procedures for preparing coin cells reduces variation due to nonuniformities and edge effects and hence improves the reproducibility of CE measurements. [1] Hobold, G. M., et al. Nature Energy 2021 6 (10), 951-960. [2] Xiao, J., et al. Nature Energy 2020 5 (8), 561-568. [3] Adams, B. D., et al. Advanced Energy Materials 2018 8 (7), 1702097. Figure 1

Yangyang Gao, Fengjun Yin, Weiqi Ma et al.

Bioelectrochemistry · 2020

The quantification of biodegradable organic matter (BOM) in polluted water plays an essential role for biodegradation-based processing of wastewater and management of water environment. Compared with the traditional detection of five-day biochemical oxygen demand (BOD 5 ), microbial fuel cell (MFC) sensors have shown an advantage for rapid and more accurate BOM assessment in several hours using coulombic yield of MFC as the signal. In this study, we propose a new calculation method that relies on the partial coulombic yield (P-CY) to further shorten the duration of the measurement. The P-CY is the cumulative coulomb at the point at which the voltage acquisition reaches a maximum voltage drop rate. The detection results with the standard GGA solution (a mixture of glucose and glutamic acid) show an enhanced linear relationship ranging from 37.5 mg L -1 to 375 mg L -1 in comparison to conventional methods. Notably, the response time for P-CY is remarkably shortened (0.99 ± 0.18-18.08 ± 0.58 h). The cutoff point for P-CY has more stable electrochemical characteristics, which enhances the accuracy of BOM detection. Furthermore, the validity of our determination of the cutoff point for P-CY is demonstrated by a mathematical model based on the Michaelis-Menten equation. Thus, the P-CY method is viable for the rapid detection of BOM in polluted water.