Hui Cai, Juan Wang, Yunfei Bu et al.

Journal of Chemical Technology & Biotechnology • 2012

Abstract BACKGROUND: For a microbial fuel cell (MFC), the anode material plays a crucial role in power output. RESULTS: A dual‐chamber MFC was constructed using carbon cloth (CC) anodes treated by concentrated nitric acid (CC‐A) and heated in a muffle furnace (CC‐H), respectively. The experiment results showed that the stable maximum voltages were 0.42–0.46 V for CC, 0.52–0.58 V for CC‐A and 0.80 V for CC‐H under the condition of a 1000 Ω external resistance, which were much higher than those reported in the literature so far. Moreover, the maximum power density of the CC‐H anode (687 mW m −2 ) was larger than for the CC‐A anode (480 mW m −2 ) and the CC anode (333 mW m −2 ). Electrochemical impedance spectroscopy (EIS) results revealed that the internal resistance was 251 Ω for CC anode, 202 Ω for CC‐A anode and 162 Ω for CC‐H anode. Scanning electron microscopy (SEM) results indicated that the increase of power generation was attributed to the increase of bacteria counts attached to anodes. The power output of the MFC increased along with the increase of the N1s/C1s ratio, which was proved by X‐ray photoelectron spectroscopy (XPS) analysis. CONCLUSIONS: Carbon cloth anodes treated by concentrated nitric acid and high temperature resulted in improved power generation by a microbiol fuel cell. © 2012 Society of Chemical Industry

Girum Ayalneh Tiruye

Sewage - Recent Advances, New Perspectives and Applications • 2022

Microbial fuel cells (MFC) are emerging as a versatile eco-friendly bioelectrochemical system (BES) that utilizes microorganisms as biocatalysts to simultaneously convert chemical energy in the chemical bond of organic and inorganic substrates into bioelectricity and treat wastewater. The performance of MFC depends on the electroactive microorganisms, popularly known as exoelectrogens, the loading rate of organic substrate, pH, MFC configurations, hydraulic retention time, and temperature. In most cases, the performance of MFC can be evaluated by measuring chemical oxygen demand (COD) removal efficiency, Coulombic efficiency and MFC power density output. To date, the most common MFC’s reactor designs are single-chamber MFC, double-chambers MFC, and stacked-MFC configurations. Generally, considerable developments in MFC systems for waste treatment, renewable energy generation and resource recovery have been made in the last two decades, despite critical challenges of capital cost investment, and low efficiency for large scale applications are impeding MFC from commercialization. This mini-review chapter provides a comprehensive assessment of principles and configurations of MFC, treatment of domestic wastewater, energy generation, and resource recovery by MFC and challenges of MFC. I believe the information provided in this chapter will enlighten the current and future prospects of versatile applications of MFC during domestic wastewater treatment.

Tobias Junginger, Lucas Tardio Ascarrunz, Azariel Ruiz Valencia et al.

• 2025

The demand for energy-efficient groundwater remediation technologies has driven interest in Microbial Fuel Cells (MFCs) as a dual solution for contaminant degradation and energy production. Although laboratory-scale MFC studies have explored the interaction between microorganisms and electrode materials, the scalability of these systems for real-world applications in heterogeneous environments remains understudied. This study presents a highly controlled and monitored field-scale MFC design aimed at optimizing power output within a 1 x 1 x 6 m flow-through tank filled with porous medium and contaminated with diesel fuel. The system utilizes stainless steel electrodes with and without activated carbon filling and anaerobic bacteria to convert diesel into electrical energy through bioelectrochemical processes.Experimental parameters—including water conductivity, flow rate, and dissolved oxygen—were held constant, while electrode material, spacing, and external resistance were systematically varied to assess their effects on power enhancement. Stainless steel electrodes emerged as the most efficient, with activated carbon reaching stable power output faster than other materials. The optimized configuration generated a stable power output of 1.1 W, coupled with an estimated degradation of 800 mg of diesel over 173 days. Additionally, microbial analysis indicated that exoelectrogenic bacteria adapted to sustain higher power generation without altering environmental conditions adversely.This work demonstrates that electrode material and spatial arrangement are key to improving MFC power output and therefore remediation efficiencies in field-scale settings. The results advance the potential of MFCs as a sustainable technology for groundwater remediation and renewable energy generation, bridging the gap between lab-scale experimentation and practical environmental applications.

Matthew Ko, Elliot Padgett, Venkata Yarlagadda et al.

Journal of The Electrochemical Society • 2021

Achieving high power performance and durability with low Pt loadings are critical challenges for proton exchange membrane fuel cells. PtCo catalysts developed on new carbon black supports show promise by simultaneously providing good oxygen reduction kinetics and local oxygen transport. We investigate the role of nanoscale morphology in the performance of these catalysts supported on accessible (HSC-e and HSC-f) and conventional (Ketjen Black) porous carbons using 3D electron tomography, nitrogen sorption, and electrochemical performance measurements. We find that the accessible porous carbons have hollow interiors with mesopores that are larger and more numerous than conventional porous carbons. However, mesopore-sized openings (>2 nm width) are too rare to account for significant oxygen transport. Instead we propose the primary oxygen transport pathway into the interior is through 1–2 nm microporous channels permeating the carbon. The increased mesoporosity in the accessible porous carbons results in a shorter diffusion pathlength through constrictive, tortuous micropores in the support shell leading to lower local oxygen transport resistance. In durability testing, the accessible porous carbons show faster rates of electrochemical surface area loss, likely from fewer constrictive pores that would mitigate coarsening, but maintain superior high current density performance at end of test from the improved local oxygen transport.

Shaimaa Nghamish Mizil

Al-Mustansiriyah Journal of Science • 2017

In this study we tried to convert the chemical energy to electrical energy by using microbial fuel cell (MFC) consist of two chambers (anode and cathode) in presence of bacteria (Escherichia coli, pseudomonas aeroginosa ) and yeast (Saccharomyces cervesia) in the anode chamber to generate electrons. The system was started with glucose concentration 5gm/l in different pH value from (5-8). From the results we get the great generation of electricity with S. cervesia at pH 5 and the maximum voltage was 833mv. In case of bacteria that used in our experiment, the suitable pH for generation the electricity was (7).

Ademola Rabiu, Myalelo Nomnqa, Daniel Ikhuomoregbe

ASME 2012 10th International Conference on Fuel Cell Science, Engineering and Technology • 2012

One of the attractions of high temperature polymer electrolyte membrane (PEM) fuel cell is the quality of the heat co-produced with power that could be recovered for use in a combined heat and power system. In this study, a one-dimensional model for a single PEM fuel cell was developed and implemented in Engineering Equations Solver (EES) environment to express the cell voltage as a function of current density among others. The single cell model was employed to investigate the energetic behaviour of a 1 kWe high temperature PEM fuel cell stack system, and the corresponding power and thermal efficiencies at different operating modes. A multiple parametric analyses using the built-in EES uncertainty propagation tool was used to determine the stack performance for the selected parameter range. The influence of the stack operating temperature, hydrogen utilization, the carbon monoxide content in the anode gas feed and the current density, on the efficiency of the fuel cell stack were studied at the required stack electrical output. The study showed that an increase in temperature increased the stack electrical power output whilst the thermal output decreased. The stack electrical power output was seen to increase with increase in the current density and hydrogen stoichiometry. It can be seen that ratio between the electrical power and thermal output increased as the current density increases. This ratio becomes unity at an operating current density of 0.3 A/cm2, representing the optimal operating current density of the stack. An increase in the hydrogen utilization has positive effects on both the cogeneration and thermal efficiency.

Lingling Gong, Mehran Abbaszadeh Amirdehi, Jayesh Sonawane et al.

ChemRxiv • 2022

Microfluidic microbial fuel cells (MFCs) hold great potential to reproduce core functions of bulk MFCs for study and optimization under precise conditions. Unlike most MFC types, those in a microfluidic format typically do not use a membrane to separate anode and cathode compartments, relying instead on the physics of laminar flow to maintain isolation of independent liquid streams. This lowers cost, device complexity, and should reduce internal resistance. However, to avoid solution crossover, which is likely to occur due to inevitable instabilities during long operational times, authors often separate electrodes by distances of several millimeters or more. This reverses benefits on internal resistance, undermining a prime advantage of microfluidic MFCs. This work demonstrates a facile method for the in-situ synthesis of a microscale membrane, supporting sub-milimeter electrode spacing. The membrane added only 68.5 Ω to the cell internal resistance and its synthesis resulted in no measurable changes to Rct at either electrode. However, the method to grow the membrane after device synthesis greatly reduced complexity in device fabrication. Overall, the reduced electrode spacing that was facilitated by the membrane lowered internal resistance from 25 k to 10 k and provide stable operation even under non-ideal flow conditions. Compared to a state-of-the-art membraneless MFC with 6 mm electrode spacing, the membrane MFC provided approximately 45% higher power density, 290% higher current density and 7 times higher acetate conversation efficiency. Membrane-enhanced flow stability also delivered continuous increases to power density with increased flow rate over baseline levels, rising to 30% higher for flow rate increases of 100 times.

Hegazy Rezk, Enas Taha Sayed, Mohammad Ali Abdelkareem et al.

International Journal of Energy Research • 2022

Summary Microbial fuel cell (MFC) is a promising technology since two important processes: wastewater treatment and electrical energy, can be obtained simultaneously. The performance of the MFC (maximum power density (MPD) and COD removal) depends mainly on substrate concentration, pH time, and initial COD. Therefore, the main target of this work is to simultaneously increase the MPD and COD removal by determining the optimal controlling parameters. The proposed methodology integrates fuzzy modelling and Harris Hawks optimization (HHO). Firstly, based on the experimental data set, an accurate fuzzy model is created to simulate the performance of MFC in terms of four controlling parameters. To prove the superiority of fuzzy model, the results are compared with response surface methodology (RSM) in terms of RMSE and coefficient of determination ( R 2 ). Secondly, using HHO, the optimal values of substrate concentration, co‐culture composition, pH, and time are determined. These four controlling parameters are used as decision variables during the optimization process, whereas the objective function is the simultaneous maximization of the MPD and COD removal. The obtained results proved that the optimal substrate concentration, pH, time, and initial COD values are 58.2%, 7, 14.4 days, and 32 × 10 −3 (mg/L) respectively. Under this condition, the integration between fuzzy and HHO, the overall performance of MFC has been improved by 10.37% and 19.13%, respectively, compared with the experimental and RSM.

Sreelakshmi Chandrasekharan, Kiruthika Sathiasivan, Jeyalakshmi Ramaswamy

Journal of Chemical Technology & Biotechnology • 2024

Abstract BACKGROUND The microbial fuel cell (MFC) is a potential cost‐effective technology for the energy‐neutral treatment of wastewater. However, the successful implementation of this technology in resource recovery is still limited. In this study, a microbial electrochemical cell was designed and operated for 30 days. Critical factors for removal and recovery of nitrogen and phosphorus as struvite from wastewater were assessed. RESULTS Optimization studies on critical factors such as the chemical oxygen demand (COD) of wastewater (500–2000 mg L −1 ) and cathode aeration rate (45–135 mL min −1 ) were conducted using a pure culture of Escherichia coli . The system yielded an average power density of 465 mW m −2 , average current density of 915 mA m −2 and phosphorus recovery at an extent of 40% as struvite. Additionally, a maximum reduction in the COD of 90% with an average coulombic efficiency of about 82% was obtained at a short interval of 30 days. Solubility studies of the recovered struvite for 12 h at different pH values from 4.5 to 9 showed a maximum solubility of 80% at pH 4.5 and a minimum of 3.5% at pH 9. CONCLUSION This study moves one step closer to applying MFC technology for nitrogen‐ and phosphorus‐rich wastewater treatment with concurrent struvite precipitation and electricity production. In this way, Sustainable Development Goals 2, 6 and 7 can be achieved through resource recovery, clean water and bioenergy. © 2024 Society of Chemical Industry (SCI).

Rudzani Sigwadi, Touhami Mokrani, Phumlani Msomi et al.

Preprints.org • 2021

To investigate the effect of acidic nanoparticles on proton conductivity, permeability and fuel cell performance, a commercial Nafion® 117 membrane was impregnated with zirconium phosphates (ZrP) and sulfated zirconium (S-ZrO2) nanoparticles. The tensile test, water uptake, methanol crossover, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermal gravimetric analysis (TGA) and Scanning Electron Microscopy (SEM) were used to assess the ca-pacity of nanocomposite membrane to function in a fuel cell. The modified Nafion® membrane obtained the higher water uptake and a lower water content angle than the commercial Nafion® 117 membrane, indicating that it has a greater impact on conductivity. Under strain rates of 40, 30 and 20 mm/min, the nanocomposite membranes demonstrate more stable thermal deterioration and higher mechanical strength, which offers tremendous promise for fuel cell applications. When compared to 0.113 S/cm and 0.013 S/cm, respectively, of commercial Nafion® 117 and Nafion® ZrP membranes, the modified Nafion® membrane with ammonia sulphate acid had the highest proton conductivity of 7.891 S/cm. When tested using a direct single cell methanol fuel cell, it had the highest power density of 183 m. cm-2 which is better than commercial Nafion® 117 and Nafion® ZrP membranes.

Susanta K. Das

ASME 2011 9th International Conference on Fuel Cell Science, Engineering and Technology • 2010

In this study, we experimentally evaluated our newly designed high temperature PEM fuel cell (HTPEMFC) prototype performance at different operating conditions. In particular, we investigated the effects of operating temperature, pressure, air stoichiometry and CO poisoning in the anode fuel stream on the current-voltage characteristics of the HTPEMFC prototype. Experimental results obtained from the single HTPEM fuel cell show that the performance is quite steady with high CO-level reformate at high operating temperature which makes it possible to feed the reformate gas directly from the reformer to the stack without further CO removal. In order to develop design parameters for fuel reformer, experimental data of this type would be very useful. The results obtained from this study showed significant variations in current-voltage characteristics of HTPEMFC at different temperatures with different CO poisoning rates. The results are promising to understand the overall system performance development strategy of HTPEMFC in terms of current-voltage characteristics while fed with reformate with different CO ratios in the anode fuel stream.

Milad Kadivarian, Ali A. Dadkhah, Mohsen Nasr Esfahany

Water Science and Technology • 2019

Abstract While microbial fuel cells are being considered as a tool for energy saving in wastewater treatment facilities, such applications in oil refineries pose a challenge due to harder acclimation of microorganisms. In this research, the effect of heat pretreating mixed culture microorganisms (MCM), and cell cross section, on the performance of a novel cell design with two cross sections (single chamber microbial fuel cells, with circular: SCMFC_CC and rectangular: SCMFC_RC cross section) fed batched with refinery wastewater were investigated. First, using original and heat pretreated MCM, the performance of SCMFC_CC in terms of chemical oxygen demand (COD) removal and electricity production was investigated. Then, using only the heat pretreated MCM, the electricity production of SCMFC_RC was measured and compared with that of SCMFC_CC. Heat pretreatment of MCM improved maximum open circuit voltage (OCV) and maximum power density generated by 14% and 16%, respectively. However, heat pretreatment reduced COD removal by about 4%. The performance of SCMFC_CC in terms of maximum OCV and power density compared to SCMFC_RC was improved by 41% and 279%, respectively. Heat treatment of MCM increases the electricity generation of the cell, while reducing the performance of COD reduction due to decreasing the microorganism varieties in the MCM.

S. Zecevic, E. M. Patton, P. Parhami

3rd International Conference on Fuel Cell Science, Engineering and Technology • 2004

This paper describes a Direct Carbon-Air Fuel Cell (DCFC) which uses a molten hydroxide electrolyte. In DCFCs, carbon is electrochemically directly oxidized to generate the power without a reforming process. Despite its compelling cost and performance advantages, the use of molten metal hydroxide electrolytes has been ignored by DCFC researches, primarily due to the potential lack of invariance of the molten hydroxide electrolyte caused by its reaction with carbon dioxide. This paper describes the electrochemistry of DCFC based on molten hydroxide electrolyte and discusses means to overcome the historical carbonate formation. Furthermore, it describes the cell performance during the initial stage of a long term operation and discusses the causes for the initial cell performance degradation. To date, five successive generations of medium temperature DCFC prototypes have been built and tested at SARA Inc. to demonstrate the technology, all using graphite rods as their fuel source. The basic feature of the cell is a simple design in which the cathode is not traditional gas fed electrode type. It is a non-porous electrode structure made of an inexpensive Fe-Ti alloy and gaseous oxygen is introduced into the cell by bubbling humid air through the electrolyte. The cell successfully demonstrated delivering more than 50 A at 0.3 V with the current density exceeding 100 mA/cm2. Main feature of DCFC with hydroxide electrolyte is that the cell performance decreases over time mainly due to oxygen cathode polarization. There are three possible causes for this performance decay: Carbonate formation, electrolyte evaporation due to air bubbling, and corrosion products build up. In order to determine the right cause for the performance decay a series of experiments was carried out investigating various parameters involving cell temperature, water content in the melt, current density, carbonate content in the melt, melt level in the cell, air flow rate and intermittent on-off operation. DCFC was operating at constant current while cell voltage and electrode potentials were recorded over time. Results obtained indicated that the performance of DCFC with hydroxide electrolyte during initial 200 h is governed by the oxygen cathode performance that is mainly affected by corrosion products. The corrosion products catalyze decomposition of peroxide ions which are reacting species at the cathode resulting in an increase of cathode polarization over time. Effect of carbonate ions on the initial cell performance decay is insignificant as compared to the effect of corrosion product. Means to overcome the corrosion products issue were discussed.

Xin Hong Peng, Xi Zhang Chu, Peng Fei Huang et al.

Applied Mechanics and Materials • 2014

Poor energy output and high cost are the key factors to inhibit the development and application of microbial fuel cells (MFCs). Different types of modification techniques for anode material are suggested to improve power performance in MFCs. nanoFe 2 O 3 is characteristics of no toxicity, biocompatibility and low cost. In this work, stainless steel mesh (SSM), ultracapacitor activated carbon with SSM (AcM), Fe 2 O 3 added AcM (AMF) anodes are investigated to improve MFCs performance. The highest maximum power density (806 ± 26 mW·m - 2 ) is obtained in AMF anode, which is 11 % higher than that of AcM (730 ± 27 mW·m - 2 ), and 57 folds higher than that of SSM anode (12 ± 0.7 mW·m - 2 ). The semi-conducting properties of passive film on the anode surface play a rather important role in anodic reaction by Mott-Schottky analysis. Tafel test demonstrates that the exchange current density (8.36×10 - 4 A·m - 2 ) is improved by 20 % for AMF compared with AcM control (6.93×10 - 4 A·m - 2 ). These results show AcM is suitable as MFCs anode, and further addition of Fe 2 O 3 can increase the extracellular electron transfer in that way increase power production in MFCs.

Adriana Solares Basurto, Mateo Pérez Ruiz, María Angélica Luján Vega et al.

Eng • 2024

This research emphasizes the effect of using Eisenia foetida in vermicompost for power generation in microbial fuel cells (MFCs). By accelerating the organic decomposition, the bioenergy generation is improved. A vermicompost-microbial fuel cell employing electrogenic microorganisms was used to convert chemical energy into electrical energy. In this work, substrates of black soil, tree bark, leaves, eggshells, and ground tomatoes were used. The vermicompost MFC has a copper cathode and a stainless steel anode. In this study, the performance of MFCs was evaluated using different numbers of Eisenia foetida specimens, with three specimens (MFCW3), five specimens (MFCW5), and seven specimens (MFCW7). Our key findings show that by increasing the number of Eisenia foetida specimens does not bring higher power densities; as a result, the best power density was observed in MFCW3 and MFCW5 at the end of the fourth week, both presenting a total of five Eisenia foetida specimens with a power density of 192 mW m−2. Therefore, optimal results were found when 330 g of substrate and five Eisenia foetida specimens were used to achieve a maximum current density of 900 mW m−2 and a maximum power density of 192 mW m−2. This type of microbial fuel cell can be considered as an alternative for power generation with a significantly reduced environmental impact, considering the use of organic waste. It can be considered a game-changer in waste management and bioenergy projects.

Naveen Jain

Advances in Nonlinear Variational Inequalities • 2024

The quest for enhanced fuel cell efficiency is pivotal in advancing sustainable energy solutions. This paper investigates novel catalyst formulations aimed at improving the performance and longevity of fuel cells. Traditional catalysts, primarily based on precious metals such as platinum, present challenges related to cost and resource availability. In response, this study explores non-precious metal catalysts (NPMCs), composite materials, and nanostructured catalysts, which have shown promising results in recent research. Through rigorous experimental methods, including synthesis and characterization techniques, we evaluate the catalytic activity and efficiency of these novel formulations. The findings demonstrate significant improvements in power output and operational durability compared to conventional catalysts. Mechanistic insights into the reaction dynamics reveal how these new materials enhance performance metrics such as current density and voltage output. An economic analysis highlights the potential for scalability and cost-effectiveness of these innovative catalysts in commercial applications. This research underscores the critical role of catalyst design in optimizing fuel cell technology and sets the stage for future explorations aimed at overcoming existing limitations in the field. By leveraging advanced materials and formulations, we aim to contribute to the development of next-generation fuel cells with enhanced efficiency and practicality.

Kumar Sonu, Monika Sogani, Zainab Syed

ChemistrySelect • 2021

Abstract The present study aims at integrating Constructed Wetland using biochar as matrix with Microbial Fuel Cell (CW‐MFC) and evaluating its effect on textile wastewater (TW) treatment in the form of removal of COD, Color and TDS along with Bioelectricity generation. Two vertical down flow systems of CW‐MFC were investigated for TW treatment and system reusability (with and without corn cob biochar) in batch mode with retention time of 10 days for 10 cycles. The performance of CW‐MFC with the corn cob biochar (CW‐MFC−A) was better than the CW‐MFC without corn cob biochar (CW‐MFC−B) in terms of parameters of TW treatment, bioelectricity generation and matrix reusability. The maximum power density, COD removal efficiency, decolorization efficiency and TDS reduction as obtained with CW‐MFC−A (102.08 mW/m 2 ; 83 %; 90 %; 84 % respectively) were higher in comparison to the values obtained in CW‐MFC−B (78.24 mW/m 2 ; 66 %; 65 %; 67 % respectively). Furthermore, the germination assessment studies using the treated effluent from CW‐MFC−A resulted in 100 % germination of Vigna radiata seeds indicating the usefulness of corn cob biochar as wetland matrix for treatment of wastewaters.

Wolfgang Winkler, Mark Williams

ASME 2008 6th International Conference on Fuel Cell Science, Engineering and Technology • 2007

This study gives information of new opportunity fuels having increasing importance is all future energy scenarios. It compares the basic thermodynamic performance of fuel cells with various fuels — ammonia, methanol, hydrogen, carbon monoxide and carbon(s). For both oxygen ion conducting and proton conducting fuel cell, where applicable, its performance as a function of utilization is considered. The fuel cell itself will be considered as a reversible electrochemical reactor, generating power and mixing substances, but without further restrictions on its design. The thermodynamic state and the excess air are further parameters of variation. The consequences of the use of air and oxygen are considered as well. The principal reversible combustion of the fuel is the base of the operation of any fuel cell. The utilisation of the fuel changes the gas concentrations on the anode and cathode side depending on the ionic transport mechanism. The reversible SOFC model was used to describe the influence of the fuel utilisation, the thermodynamic state, and the operational parameters for the fuel H2 on the local Nernst voltage in previous publications. This work has been expanded to proton conducting cells and different opportunity and hydrocarbon fuels. Ammonia is quite different and at lower utilizations appears to be a superior fuel. Methanol is superior to methane over a wide utilization range. Hydrocarbons like methane have a smaller voltage decrease during utilization than hydrogen and carbon monoxide. Excess air larger than two has a small impact on voltage loss. Direct utilization of hydrocarbon fuels without reforming is a key development path toward higher efficiency.

Marcelinus Christwardana, Linda Aliffia Yoshi

International Journal of Renewable Energy Development • 2020

The Microbial fuel cells (MFCs) are electrochemical devices that can be utilized as biosensors, specifically Dissolved Oxygen (DO) biosensors. In this research, performance and techno-economic of MFC-based DO biosensors with two sizes, small and large, were evaluated and analysed to determine whether it is more economical to use a small or large reactor. MFC-based DO biosensors were also applied to an irrigation canal. When MFC immersed into distilled water with several variations of DO, the correlation between DO and current density produced equation with R2 values around 0.9989 and 0.9979 for SYMFC and LYMFC, respectively. The power density for SYMFC and LYMFC was 3.48 and 10.89 mW/m2, respectively, in DO 6. Higher power densities are correlated with the electrode surface area, especially the larger cathodic surface area. When applied to the irrigation canal, DO values measured using SYMFC and LYMFC have errors of around 3.39 and 4.42%, respectively, when compared to DO values measured using DO meters. LYMFC requires a capital cost of around $ 234.22 or 2.57 times higher than SYMFC, although it generates almost similar cost per mW/m2, $ 21.51 and $ 26.23 for LYMFC and SYMFC, respectively. The results concluded that yeast MFC -based DO biosensors with smaller sizes can achieve more economical compared to larger sizes.

Dani Permana, Herlian Eriska Putra, Oman Rohman et al.

Indonesian Journal of Biotechnology • 2024

A suitable wastewater treatment system is required due to the high organic compound content in tofu wastewater, which can harm the environment. Biological treatment methods are effective for treating tofu wastewater due to its characteristics. Microbial fuel cells (MFCs) represent one such biological treatment option, effectively removing organic contaminants while generating low‐power electricity through bioenergetic reactions. In MFCs, microorganisms are used as biocatalysts to degrade the organic compounds present in wastewater. This study aimed to assess the efficacy of Salt‐bridge microbial fuel cells (SB‐MFC) using various acclimatized microbe cultures for reducing organic compounds and generating energy from tofu wastewater. Tofu wastewater was sterilized prior to introduction into the reactor. Additional microbes, including the native microbe consortium from tofu wastewater, Escherichia coli, Saccharomycopsis fibuligera, and a mixed culture of E. coli and S. fibuligera, were then introduced as biocatalysts. Carbon electrodes were utilized as both the anode and cathode. The results indicate that the mixed culture of E. coli and S. fibuligera significantly reduced COD and BOD5 levels, with removal rates of 82.74% and 76.53%, respectively, after 48 h. Furthermore, the culture generated a voltage of 676 mV, a current of 2.53 mA, a power density of 428 mWatt/m2, and 4.789×10‐2 kWh of energy. This study contributes to the advancement of SB‐MFC by utilizing wastewater and a combination of bacteria and yeast as biocatalysts.

Peng Cheng, Rui Shan, Hao-Ran Yuan et al.

bioRxiv (Cold Spring Harbor Laboratory) • 2018

Abstract Electron transfer from microorganisms to the electrode is the key process in microbial fuel cells (MFCs). In this study, a trehalose lipid was added to a Rhodococcus pyridinivorans-inoculated MFC to improve the power output by enhancing electron transfer. Upon trehalose lipid addition, the current density and maximum power density were increased by 1.83 times and 5.93 times, respectively. Cyclic voltammetry analysis revealed that the addition of trehalose lipid increased the electron transfer performance, while electrochemical impedance spectroscopy results proved a decrease in internal resistance. Microscopy images showed that the trehalose lipid-treated bacteria interacted more closely with various fagellum-like contacts, while in the pure trehalose lipid (200 mg/L), pores were obviously observed in the cell surface. Importance Improving the power output of microbial fuel cells by the addition of bio-surfactants have been proved to be a novel method. However, only rhamnolipid and sophorolipid are certified to be effective. Trehalose lipid is a common material in cosmetic and bio-medicine industry. Our research broaden the application of bio-surfactant in MFC and preliminarily explain the mechanism. Highlights Trehalose lipid enhanced MFC power generation Trehalose lipid decrease MFC internal resistance Pores were observed with the addition of trehalose lipid Addition of bio-surfactant is a promising way to increase MFC performance

Maha A. Allawi Abdulwahhab, Sarmad talib Najim

Research Square • 2023

Abstract This study compared the performance of microbial fuel cells (MFCs) using parchment paper as a separator to a CMI7000 proton exchange membrane. The MFCs were operated in two chambers with whey solution as the substrate. Parameters such as COD removal, internal resistance, power density, current density, and Columbic efficiency ratio (CE) were evaluated. The CMI7000 membrane exhibited the highest COD removal at 92%, while the parchment paper achieved removal percentages ranging from 72–91%. The internal resistance was lower for the parchment paper separator for the first run, the internal resistances were 68 and 84 for parchment paper and CMI7000, respectively. The maximum energy densities were 219 mW/m (5.74 mA/m) and 421 mW/m (8.24 mA/m) for parchment paper and CMI7000 membrane, respectively. The CE values for parchment paper were 36.32 and 33.5, while for the CMI7000 membrane, they were 42.73 and 32.0, for the two runs. Overall, the study demonstrated that the parchment paper separator performed reasonably well in terms of COD removal, internal resistance, energy density, and Columbic efficiency ratio compared to the CMI7000 membrane in microbial fuel cells.

Akanksha Mishra, Meenu Chhabra

Research Square • 2023

Abstract This present study investigated the effect of co-culturing the photobiont and mycobiont in the microbial fuel cell (MFC) cathode for lipid generation. Chlorella vulgaris provides oxygen and nutrients for the yeast Cystobasidium oligophagum JRC1 while latter provides CO 2 and quench oxygen for higher algae growth. Co-culture enhanced the lipid output of biomass by 28.33%. The total lipid yield and productivity with co-culture were 1.47 ± 0.18 g/L and 0.123 g/L/day respectively. The MFC attained open circuit voltage of 685 ± 11 mV. Synthetic wastewater was used at the anode with sodium acetate as a substrate. The power density of the system was 5.37 ± 0.21 mW m -2 with 75.88 ± 1.89% of COD removal. The total energy output (Lipid + Electrical energy) from the co-culture MFC was 11.5 ± 0.035 kWh m -3 which was 1.4-fold higher than algae alone.

Alok Tiwari, Niraj Yadav, Dipak A. Jadhav et al.

Environmental Engineering Research • 2024

The membrane employed in microbial fuel cells (MFC) stands as a pivotal component, comprising more than half of the overall construction cost of the assembled MFC. This study introduces a novel earthen membrane, crafted by inclusion of wood ash in different weight ratios, providing a low-cost substitute to the conventional Nafion 117 membrane. Among the fabricated membranes, X3, engineered with red soil and 20% wood ash exhibits superior performance. The inclusion of wood ash enhances proton transport and mitigates oxygen diffusion into the anode, while also augmenting the ion exchange capacity of the fabricated membrane. The MFC equipped with the X3 membrane (MX3) demonstrates the highest COD removal (93.89±0.73%) and coulombic efficiency (66.10±2.53%). Notably, MX3 achieves a remarkable power density (Pmax: 1450.09±151.3 mW/m3), surpassing all other microbial fuel cells and marking a 9.8-fold increase in comparison to the control MFC. This study underscores the potential of the X3 membrane as a novel and economically viable alternate to Nafion 117 membrane.

N. Samsudeen, Shivanand Chavan, T. K. Radhakrishnan et al.

Journal of Renewable and Sustainable Energy • 2016

The effect of chemically synthesized activated carbon (AC) on the performance of microbial fuel cell (MFC) was investigated in this study. Coconut fiber was used as a source material for synthesizing the AC. The AC with different ranges (5, 10, and 15 mg/cm2) was coated on the anode electrode surface to investigate and compare the performance of MFC with the control electrode (plain surface). The experimental results showed that the AC-5 (5 mg/cm2) coated electrode produced a peak power density (5.8 W/m3) which was higher than the control (plain) electrode (3.8 W/m3). The MFC performance in terms of power density and chemical oxygen demand (COD) removal efficiency was increased with increasing loading quantity of AC. When an AC-15 (15 mg/cm2) coated was electrode used in the MFC, the highest power density of 9.5 W/m3 with a COD removal efficiency of 74.8% was observed. Cyclic voltammetry analysis visualized the clear enhancement in electrochemical activity with an AC coated electrode. The effect of wastewater COD concentration on the performance was also investigated. The AC derived from coconut fibers can be considered as a biocompatible material to enhance MFC performance.

Deepak Lohani, Anupam Gautam

International Journal For Multidisciplinary Research • 2025

Wastewater treatment has traditionally been an energy intensive process, consuming between 950 and 2850 kJ/m3 of wastewater treated. By one account, wastewater contains 9.3 times more energy than is used to treat an equivalent volume, thus creating the desire to harness this energy through the use of a Microbial Fuel Cell (MFC). MFCs oxidize organic substrates, allowing simultaneous wastewater treatment and electricity generation. Previous research has primarily focused on the development of MFCs for electricity generation, mainly at the small, laboratory scale. Herein, an industrial-scale MFC process is proposed for the treatment of wastewater from a microbrewery based on a previously published model describing MFC operation. Through optimization and scale-out, a two chamber MFC process is developed for the treatment of wastewater with an inlet Chemical Oxygen Demand (COD).

Dena Z Khater, Rabab S Amin, Monera O Zhran et al.

Research Square • 2021

Abstract Mixed transition metal (Ni & Cu) oxides supported on graphene (NiO-CuO/G) electrocatalyst was fabricated and tested as an efficient and cost-effective cathode for oxygen reduction reaction (ORR) in microbial fuel cells (MFCs). The electrocatalytic activity and selectivity of the NiO-CuO/G for ORR were examined using linear sweep voltammetry measurements (LSV) on a rotating disc electrode (RDE) in pH-neutral electrolyte. In comparison with a benchmark platinum cathode, the NiO-CuO/G showed high selectivity towards the ORR. The analysis of Koutecky-Levich relationship suggests that the electrocatalyst follows the four-electron ORR pathway. NiO-CuO/G cathode in an air-cathode MFC exhibited a slightly lower power density 21.25 mWm − 2 compared to 50.4 mW m − 2 for Pt/C. Both scanning and transmission electron microscope analyses of anodic biofilm showed that a thick biofilm was successfully developed with a rod-like shape. Biochemical characterization of the communities showed that four genera named Escherichia coli ( E-coli ), Shewanella putrefaciens , Bacillus cereus and Bacillus Thuringiensis/mycoides , which belonging to GammaProteobacteria and Firmicutesphyla thatwerethe most abundant bacteria in the anodic biofilm. Our results revealed that NiO-CuO/G cathode demonstrates an enhanced electrocatalytic activity toward ORR in a pH-neutral solution; thus, the newly developed mixed transition metal oxides electrocatalyst can replace other expensive Pt-based catalysts for MFC application.

Sudhir V Ambekar, Makarand M Ghangrekar

Journal of Environmental Engineering and Science • 2022

Microbial fuel cells (MFCs) have proven to be an effective technology for treatment of waste water with the additional advantage of electricity generation. Although the power density obtained has increased manyfold over the past decade, the cost of treatment and cost of electricity generation need to be brought down to make the process feasible. In the present research, an attempt was made to use locally available, low-cost and effective materials for the construction of an MFC using novel anode architecture. The MFC was made using multiple membranes in a single cell. The special design of the anode proved to be very effective in obtaining a higher power density. A volumetric power density of 2002 mW/m 3 could be achieved without the use of any chemical catholyte. The corresponding coulombic efficiency obtained was 13.17%. When a chemical catholyte was used, the power density increased to 5201 mW/m 3 , an increase by more than 2.5 times. The corresponding coulombic efficiency of the MFC also increased to 29.16%. Such novel anode architecture could take this technology a step forward for practical implementation to harvest carbon dioxide neutral electricity from waste water. The performance of the MFC in the removal of chemical oxygen demand (COD) from waste water was found to be 93.9–97.75%, which is highly satisfactory. The removal efficiency was found to be independent of the initial COD of the substrate.

Jiaqi Lv, Weiye Wang, Qingliang Zhao et al.

Environmental Engineering Research • 2022

Microbial fuel cell powered electro-Fenton system (MFCⓅEFs) is a self-sustainable energy conversion process to degrade refractory pollutants utilizing green biomass energy. Most previous works usually employed innovative cathode to minimize electron transfer losses but neglected the development of high-efficiency anode to enhance electron generation. The synergy of polyaniline (PANI) and MnO<sub>2</sub> on electrode could improve charge accessibility and facilitate rapid electron transfer due to its superior conductivity and capacitance, which had not been applied to MFCⓅEFs as anode so far. In this study, a PANI-Mn/CF (carbon fiber loaded with polyaniline and MnO<sub>2</sub>) composite anode was introduced into MFCⓅEFs to enhance interface activity and realize more efficient electricity generation and pollutant degradation. Experimental results showed that a higher power density (5.49 times that of the original CF) and lower ohmic resistance (7.17 Ω) occurred in the MFCⓅEFs with PANI-Mn/CF anode, which consumed more sewage sludge (37.14% of TCOD removal), leading to achieving more effective pollutant degradation (93.03% of tetracycline hydrochloride removal). Overall, this study provided an innovative way of thinking and approach to efficient utilization of biomass waste and degradation of refractory pollutants with the merits of environmental sustainability.

Adrianna Nogalska, Andreu Bonet Navarro, Ricard Garcia-Valls

Membranes • 2020

Membrane electrode assemblies (MEAs) with palladium catalysts were successfully prepared by using a home-made manual pressing system with Nafion glue application that contributed to a decrease of additional energy consumption. The catalyst coated membranes were prepared with supported palladium on activated carbon (PdC) and unsupported palladium black (PdB) for comparison. The performance of passive, air breathing, functioning under ambient conditions and with low concentration (1 M) formate/formic acid fuel cell was evaluated. Based on polarization curves, the best result was obtained with carbon supported catalyst and HCOOK fuel, achieving 21.01 mW/mgPd. Still, constant current discharge with PdC showed an energy generation efficiency of 14% with HCOOH over 3% with HCOOK caused by lower potassium ion conductivity and its permeability through the proton exchange membrane. The faradic efficiency of conversion in the cell is equal to the overall energy efficiency and makes the cell self-sufficient.

Melisa Acosta-Coll, Adalberto Ospino-Castro, Stalin Carbonell-Navarro et al.

Preprints.org • 2019

Plants Microbial Fuel Cells (PMFC) is a new technology that generates electricity in a renewable, clean and sustainable way. In spite of these advantages, it still faces limitations in power generation and current density, reaching lower production values than other renewable technologies. Different studies maintain that the high resistivity of the cathode is the main limitation in the generation of energy; therefore, non-metallic materials to obtain a better performance are replacing the metallic electrodes. The implementation of these materials applied to PMFC requires a complex interdisciplinary work. Through three experimental tests using metallic electrodes for the extraction of electrons, this research study shows that the treatment of the substrate with natural materials, the volume plant roots, and substrate temperature and humidity control have a significant influence in the increase of the electric potential and the generated current.

Mohammed Yousri Silaa, Mohamed Derbeli, Oscar Barambones et al.

Sustainability • 2021

Taking into account the restricted ability of polymer electrolyte membrane fuel cell (PEMFC) to generate energy, it is compulsory to present techniques, in which an efficient operating power can be achieved. In many applications, the PEMFC is usually coupled with a high step-up DC-DC power converter which not only provides efficient power conversion, but also offers highly regulated output voltage. Due to the no-linearity of the PEMFC power systems, the application of conventional linear controllers such as proportional-integral (PI) did not succeed to drive the system to operate precisely in an adequate power point. Therefore, this paper proposes a robust non-linear integral fast terminal sliding mode control (IFTSMC) aiming to improve the power quality generated by the PEMFC; besides, a digital filter is designed and implemented to smooth the signals from the chattering effect of the IFTSMC. The stability proof of the IFTSMC is demonstrated via Lyapunov analysis. The proposed control scheme is designed for an experimental closed-loop system which consisted of a Heliocentric hy-Expert™ FC-50W, MicroLabBox dSPACE DS1202, step-up DC-DC power converter and programmable DC power supplies. Comparative results with the PI controller indicate that a reduction of 96% in the response time could be achieved using the suggested algorithm; where, up to more than 91% of the chattering phenomenon could be eliminated via the application of the digital filter.

David M. Mackie

• 2016

Applications for bio-hybrid fuel cells (BHFCs) and other weak energy sources would greatly benefit from highly-efficient power compression that substantially increased the voltage and also allowed intermittent draws of high current. The assumption of a weak energy source necessitates also minimizing parasitic energy draws. We present results for a power compressor composed of a boost converter (variable voltage upconversion), a harvest regulator (matching impedances on the fly), and a bank of low-leakage capacitors (high current draw for short times). The power compressor was not externally powered. Performance was evaluated while connected to two direct ethanol fuel cells (DEFCs) in series, for periods of 3 and 10 days. The DEFCs' design was not optimized for power. They were non-flowing, room-temperature, air-cathode, PtRu/Pt units, which simulated the output of small BHFCs. The power compressor automatically kept the DEFCs close to the voltage yielding maximum power output, which was 400 mV for two DEFCs in series. The output voltage of the capacitor bank was repeatedly raised to 10.25 V and then discharged to 5 V through a resistor. Energy efficiency of the power compressor was uniformly 50%, except for very weak input power.

Yuyang Wang

Coatings • 2024

Anode materials play a crucial role in the performance of microbial fuel cells (MFCs) in terms of power output. In this study, carbon nanotube (CNT)/polyaniline (PANI)/chitosan (CS) composites were prepared on a porous sponge matrix. The high electrical conductivity of CNTs, the capacitive behavior of PANI, and the biocompatibility of CS were leveraged to enhance the electricity generation and energy storage capabilities of MFCs. Experimental results demonstrated that the MFC with the modified anode achieved a maximum power density of 7902.4 mW/m3. Moreover, in the charging–discharging test, the stored electricity of the S/CNT/PANI/CS anode was 16.38 times that of the S/CNT anode when both the charging and discharging times were 30 min. High-throughput sequencing revealed that the modified composite anode exhibited remarkable biocompatibility and selective enrichment of electrogenic bacteria. Overall, this study presents a novel approach for developing composite MFC anode materials with energy storage functionality.

A. Janicek, N. Gao, Y. Fan et al.

Fuel Cells • 2015

Abstract Replacing precious metal catalysts by inexpensive activated carbon (AC) is a breakthrough in microbial fuel cell (MFC) cathode fabrication. In this study, AC powders made from bamboo, peat, coal, coconut, and hardwood sources are evaluated in terms of their electrochemical performance with carbon cloth as the base material. These ACs are characterized in terms of their conductivity, surface chemistry, surface area, and pore size distribution. The bamboo‐based AC demonstrates the highest potential for use as a catalyst for carbon cloth based cathode, reaching 10.6 A m −2 at 0V vs. Ag/AgCl and a loading of 25 mg cm −2 . The maximum power density reached 3.3 W m −2 in CEA–MFCs. The high performance of the bamboo‐based AC cathode was possible due to the good conductivity and suitable surface chemistry of the bamboo AC and the high surface area of the base material. The hydrostatic pressure tolerance of the AC carbon cloth cathode is greater than 1.8 m, allowing for a more versatile cathode, suitable for use in many different reactor configurations.

A. Jamekhorshid, G. Karimi, X. Li

ASME 2009 7th International Conference on Fuel Cell Science, Engineering and Technology • 2008

Non-uniform current distribution in polymer electrolyte membrane fuel cells results in local over-heating, accelerated ageing, and lower power output than expected. This issue is very critical when fuel cell experiences water flooding. In this work, the performance of a PEM fuel cell is investigated under cathode flooding conditions. A partially flooded GDL model is proposed to study local current density distributions along flow fields over a wide range of cell operating conditions. The model results show as cathode inlet humidity and/or cell pressure increase the average current density for the unflooded portions of the cell increases but the system becomes more sensitive to flooding. Operating the cell at higher temperatures would lead to higher average current densities and the chance of system being flooded is reduced. In addition, higher cathode stoichiometries prevent system flooding but the average current density remains almost constant.

Imologie Meshack Simeon, Alfons Weig, Ruth Freitag

Biotechnology for Biofuels and Bioproducts • 2022

Abstract Background Microbial fuel cells (MFCs) are among the leading research topics in the field of alternative energy sources due to their multifunctional potential. However, their low bio-energy production rate and unstable performance limit their application in the real world. Therefore, optimization is needed to deploy MFCs beyond laboratory-scale experiments. In this study, we investigated the combined influence of electrode material (EM), electrode spacing (ES), and substrate feeding interval (SFI) on microbial community diversity and the electrochemical behavior of a soil MFC (S-MFC) for sustainable bio-electricity generation. Results Two EMs (carbon felt (CF) and stainless steel/epoxy/carbon black composite (SEC)) were tested in an S-MFC under three levels of ES (2, 4, and 8 cm) and SFI (4, 6, and 8 days). After 30 days of operation, all MFCs achieved open-circuit voltage in the range of 782 + 12.2 mV regardless of the treatment. However, the maximum power of the SEC–MFC was 3.6 times higher than that of the CF–MFC under the same experimental conditions. The best solution, based on the interactive influence of the two discrete variables, was obtained with SEC at an ES of 4.31 cm and an SFI of 7.4 days during an operating period of 66 days. Analysis of the experimental treatment effects of the variables revealed the order SFI < ES < EM, indicating that EM is the most influential factor affecting the performance of S-MFC. The performance of S-MFC at a given ES value was found to be dependent on the levels of SFI with the SEC electrode, but this interactive influence was found to be insignificant with the CF electrode. The microbial bioinformatic analysis of the samples from the S-MFCs revealed that both electrodes (SEC and CF) supported the robust metabolism of electroactive microbes with similar morphological and compositional characteristics, independent of ES and SFI. The complex microbial community showed significant compositional changes at the anode and cathode over time. Conclusion This study has demonstrated that the performance of S-MFC depends mainly on the electrode materials and not on the diversity of the constituent microbial communities. The performance of S-MFCs can be improved using electrode materials with pseudocapacitive properties and a larger surface area, instead of using unmodified CF electrodes commonly used in S-MFC systems.

Leyuan Zhang, Yucheng Zhang, Yang Liu et al.

ChemRxiv • 2024

Microbial fuel cells (MFCs) utilize exoelectrogenic microorganisms to directly convert organic matter into electricity, offering a compelling approach for simultaneous power generation and wastewater treatment. However, conventional MFCs typically require thick biofilms for sufficient metabolic electron production rate, which inevitably compromises mass and electron transport, posing a fundamental tradeoff of limiting the achievable power density (<1 mW cm-2). Herein, we report a new concept of redox mediated microbial flow fuel cells (MFFCs) by exploiting artificial redox mediators in flowing medium to efficiently transfer metabolic electrons from bacteria to electrodes, which effectively overcomes mass transport limitations and markedly reduces internal resistance. The biofilm-free MFFC thus breaks the inherent tradeoff in dense biofilms, resulting in a maximum current density surpassing 40 mA cm-2 and a highest power density exceeding 10 mW cm-2, approximately one order of magnitude higher than those of state-of-the-art MFCs, to the best of our knowledge.

Hoang Dung Nguyen, Sandhya Babel

Suranaree Journal of Science and Technology • 2024

This study explores the utilization of a cation exchange membrane (CEM) in a microbial fuel cell (MFC) system to isolate nitrogen from wastewater influents. While employing a CEM in an MFC system has drawbacks, such as increased internal resistance and reduced power output, it also provides a means for optimal energy recovery from organics while allowing isolated nitrogen to be treated in subsequent steps. This study evaluated the diffusion of ammonium through CEM in a dual-chamber MFC under different operating conditions. Results indicated that the MFC reactor with CEM as a separator isolated 88-93% of the nitrogen input, demonstrating the feasibility of this approach for nitrogen separation in wastewater treatment applications. Factors affecting nitrogen isolation, including COD input at the anode, dissolved oxygen (DO) at the cathode, and external resistance (ER), are identified. Higher COD input at the anode and the DO at the cathode were found to enhance nitrogen separation, while increased ER had an adverse effect on nitrogen isolation capacity. Additionally, changes in the surface characteristics of the CEM during operation could impact nitrogen isolation, emphasizing the need for careful monitoring and maintenance of the CEM to ensure consistent performance over time. In conclusion, this study highlighted the potential of using a CEM in MFC systems for nitrogen isolation, provided insights into the factors affecting the efficacy of nitrogen separation, and underscored the need for monitoring and maintenance of the CEM. These results could significantly impact the development of more efficient and sustainable wastewater treatment using the MFC system.

Mustapha Abdeldjabar Charef, Hakima Kebaili, Mostefa Kameche et al.

Indonesian Journal of Chemistry • 2021

A Microbial Fuel Cell (MFC) was conceived by using garden soil as a source to culture. It was then utilized as a bio-catalyst to decompose waste organic matter, reduce pollution from the soil, and produce energies. The MFC was composed of a bio-anode inoculated with a mixture of garden compost leachate and an abiotic stainless steel cathode. Besides, the bio-anode consisted of a Nafion membrane modified with carbon. The microorganisms agglomerated under polarization and formed electroactive bio-film onto bio-anode. In the preliminary test of MFC, potassium hexacyanoferrate has been utilized as catholyte, to enhance the reduction of proton and electrons resulting in a higher voltage. However, this electrolyte is toxic and oxidized rapidly, thus substituted by the hydrochloric acid. The results showed that the MFC with modified Nafion, gave relatively high current-density 379 mA/m2 in two days, whereas the conventional biofuel cell without modification attained the current-density 292 mA/m2 in four days. Nevertheless, both cells yielded almost the same current density of 20 mA/m2 during 60 days. Although it has been used for a long time, the modified Nafion has not been corroded and preserved its physicochemical properties.