, Abimbola Motunrayo Enitan

• 2015

Anaerobic digestion, a proven and highly efficient biological process for treating industrial wastewater and biogas generation is an underutilized technology in South Africa. Some of the industries that have on-site anaerobic reactors tend to face problems in operating these reactors due to poor understanding of the process and implementation of the technology. This has resulted in high pollutant loads in their final effluents and low energy recovery. In this study, an on-site full–scale upflow anaerobic sludge blanket (UASB) reactor treating brewery wastewater was extensively monitored in order to evaluate the efficiency in terms of effluent quality, biogas production and microbial structure. Furthermore, developed and adopted kinetic models were used to optimize the performance of the full–scale UASB reactor using a combined Pareto differential evolution (CPMDE) algorithm. A preliminary analysis of the raw wastewater has shown that the wastewater produced from the brewery industry was high in organic matter with a total chemical oxygen demand (COD) between 1096.41 to 8926.08 mg/L. The average removal efficiency of COD from the UASB reactor after treatment was 79% with a methane (CH4) production of 60-69% at temperature ranges of 28-32˚C and hydraulic retention time (HRT) of 12 h within the optimal pH range for anaerobic bacteria (6.6 and 7.3) under various organic loading rates. However, the results also showed an increase in total suspended solids (TSS), nitrogen (N2), ammonia (NH3) and orthophosphate concentrations when comparing the influent to the effluent, which indicated the necessity for further optimization of the reactor condition in order to reduce these effluent parameters to acceptable standards and to increase CH4 production. In order to optimize the process, a thorough understanding of microbial interaction was essential. A combination of different molecular techniques viz., fluorescence in–situ hybridization (FISH), polymerase chain reaction (PCR) and quantitative real-time PCR (QPCR) were employed to understand the microbial community structure of the granular sludge samples using species specific primers and probes. The results revealed that the dominance of diverse groups of eubacteria belonging to phyla Proteobacteria, Firmicutes and Chloroflexi and an uncultured candidate division WS6 with four different orders of methanogenic Archaea viz., Methanomicrobiales, Methanococcales, Methanobacteriales and Methanosarcinales belonging to hydrogenotrophic and aceticlastic methanogens were within the reactor samples. Quantification of the 16S rDNA copies of eubacteria and methanogenic Archaea using species-specific primers further confirmed the spatial distribution of these microorganisms within the different compartments of the reactor where, the upper compartments were dominated by eubacteria and the lower compartments by methanogenic Archaea. The concentration of Archaea per nanogram of DNA was much higher (96.28%) than eubacteria (3.78%) in lower compartments, while, the eubacteria concentration increased to 98.34% in upper compartments with a decrease in Archaea quantity (1.66%). A modified kinetic methane generation model (MMGM) was developed on the basis of mass balance principles with respect to substrate (COD) degradation and the endogenous decay rate to predict CH4 production efficiency of the reactor. Furthermore, a Stover–Kincannon kinetic model was adopted with the aim of predicting the final effluent quality in terms of COD concentration and model coefficients were determined using the data collected from the full–scale reactor. Thereafter, a model-based multi-objective optimization was carried out using the CPMDE algorithm with three–objective functions namely; maximization of volumetric CH4 production rate; minimization of effluent substrate concentration and minimization of biomass washout, in order to increase the overall efficiency of the UASB reactor. Important decision variables and constraints related to the process were set for the optimization. A set of non-dominated solutions with high CH4 production rates of between 2.78 and 5.06 L CH4/g COD/day at low biomass washout concentrations were obtained at almost constant solution for the effluent COD concentration. A high COD removal efficiency (85-87%) at ~30-31˚C and 8-9 h HRT was obtained for the multi-objective optimization problem formulated. This study could significantly contribute towards optimization of a full–scale UASB reactor treating brewery wastewater for better effluent quality and biogas production. Knowledge on the activity and performance of microbial community present in the granular sludge taken from the full–scale UASB reactor would contribute significantly to future optimization strategies of the reactor. In addition, optimization using an evolutionary algorithm under different operational conditions would help to save both time and resources wasted in operating anaerobic bioreactors.

Ziyi Shi, Yanghao Jin, Tong Han et al.

Scientific Reports • 2024

Abstract Producing sustainable anode materials for lithium-ion batteries (LIBs) through catalytic graphitization of renewable biomass has gained significant attention. However, the technology is in its early stages due to the bio-graphite's comparatively low electrochemical performance in LIBs. This study aims to develop a process for producing LIB anode materials using a hybrid catalyst to enhance battery performance, along with readily available market biochar as the raw material. Results indicate that a trimetallic hybrid catalyst (Ni, Fe, and Mn in a 1:1:1 ratio) is superior to single or bimetallic catalysts in converting biochar to bio-graphite. The bio-graphite produced under this catalyst exhibits an 89.28% degree of graphitization and a 73.95% conversion rate. High-resolution transmission electron microscopy (HRTEM) reveals the dissolution–precipitation mechanism involved in catalytic graphitization. Electrochemical performance evaluation showed that the trimetallic hybrid catalyst yielded bio-graphite with better electrochemical performances than those obtained through single or bimetallic hybrid catalysts, including a good reversible capacity of about 293 mAh g −1 at a current density of 20 mA/g and a stable cycle performance with a capacity retention of over 98% after 100 cycles. This study proves the synergistic efficacy of different metals in catalytic graphitization, impacting both graphite crystalline structure and electrochemical performance.

Jasreet Kaur, Amandeep Singh Pannu, Muhammad J. A. Shiddiky et al.

Advanced Sustainable Systems • 2024

Abstract To address the fundamental challenge of resource sustainability and to effectively deal with issues pertaining to supply chain resilience, cost efficiency, environmental impact, and the ability to meet specific local needs; there is an urgent need for high‐grade battery anode materials produced locally from readily available raw materials. In this work, synthesis of high‐quality graphitic carbon (GH) derived from human hair is demonstrated using an in‐house engineered reactor based on Joule's Flash heating method. The GH is characterized using various techniques to examine its chemical composition, particle morphology, crystallinity, and demonstrate its usability as an anode material for lithium‐ion batteries. Fabricated coin cell with active material exhibits a gravimetric capacity of 320 mAh g −1 at a current density of 30 mA g −1 (equivalent to a C rate of ≈0.1C) over the 100 cycles. The in situ and ex situ studies using XRD, Raman, XPS, and UPS techniques conclude that during the initial charge cycle for GH, lithium ions diffused into the electrode during the resting period are effectively removed. This not only improves the lithium inventory to start with but also mitigates subsequent solvent degradation during solid electrolyte interphase (SEI) formation. Thus, these improvements ultimately enhance the capacity of the anode to 500mAh g −1 at a current density of 20 mA g −1 . The study offers the potential to initiate a new realm of research by redirecting the focus to a material once considered as mere waste.

Mario Culebras, Hugh Geaney, Anne Beaucamp et al.

ChemSusChem • 2019

Abstract Development of cost‐effective and increasingly efficient sustainable materials for energy‐storage devices, such Li‐ion batteries, is of crucial future importance. Herein, the preparation of carbon nanofibres from biopolymer blends of lignin (byproduct from the paper and pulp industry) and polylactic acid (PLA) or a thermoplastic elastomeric polyurethane (TPU) is described. SEM analysis shows the evolving microstructural morphology after each processing step (electrospinning, stabilisation and carbonisation). Importantly, it is possible to tailor the nanofibre porosity by utilising miscibility/immiscibility rules between lignin and the polymer additive (PLA/TPU). PLA blends (immiscible) generate porous structures whereas miscible lignin/TPU blends are solid when carbonised. Electrodes produced from 50 % PLA blends have capacity values of 611 mAh g −1 after 500 charge/discharge cycles, the highest reported to date for sustainable electrodes for Li‐ion batteries. Thus, this work will promote the development of lignocellulose waste materials as high‐performance energy‐storage materials.

Zhihan Gao, Bo Wang, Jinhua Liu et al.

Materials Research Express • 2023

Abstract Non-calcined petroleum coke can serve as an anode material for lithium-ion batteries (LIBs). Nevertheless, this method results in materials with insufficient conductivities and low Coulombic efficiencies during the initial cycle. To address these challenges, the usage of pre-baked carbon anodes as a material for anodes in LIBs is proposed in this study. The surface features of the pre-baked anode (i.e. wrinkle-like filaments) aid in reducing the volume expansion of the electrode during the lithium-ion insertion–removal process. Furthermore, the treatment increases the particle contact area, improving the conductivity of the pre-baked anode. At a current density of 3 A g −1 , the pre-baked anode demonstrated an initial discharge capacity and a stable discharge capacity of 548.7 and 134.5 mAh g −1 , respectively, after 100 cycles. The capacity of the anode (after 1000 cycles) consistently varies within a narrow range at a current density of 3 A g −1 , indicating the stability of the electrode capacity over extended use. Therefore, this study provides valuable insights into exploring potential applications of pre-baked anode materials.

Wei He, Zihao Su, Meizhen Qu et al.

Chemistry – A European Journal • 2025

Abstract Silicon (Si) is considered to be one of the most promising anode materials for next‐generation lithium‐ion batteries because of its abundant reserves, low discharge potential, and most importantly, its high theoretical specific capacity. However, the practical application of Si‐based anodes is mainly hindered by the low intrinsic conductivity of Si and the large volume change upon lithiation/de‐lithiation. In order to improve the electrochemical performance of Si‐based anodes, we prepared a composite material consisting of Si nanoparticles (NPs) and coconut silk bio‐carbon (CSC) skeleton. The porous carbon skeleton derived from coconut silk with natural through‐holes and ample micropores on the wall, which was used as the carrier of Si NPs. The continuous through‐holes and well‐distributed oxygen‐containing functional groups of the CSC provided sufficient space and abundant adsorption active sites for Si NPs, what‘s more, the good dispersion of Si NPs in the through‐holes increased their contact with the surrounding carbon materials, which was conducive to electron transport. Meanwhile, the pore structure also provided buffer space for the volume expansion of Si. The rich oxygen‐containing functional groups can form a certain chemical force with silicon particles, and further stabilize the nano silicon particles. Hence, the CSC/Si electrode revealed an excellent capacity retention of 82.8 % at 1 A g −1 after 100 cycles. This study provides a simple universal high‐throughput method to obtain anode materials with outstanding electrochemical properties and promotes the further development of Si/C composites.

Yan Qiao, Xiao-Shuai Wu, Cai-Xia Ma et al.

RSC Adv. • 2014

A three-dimensional graphene/nickel composite electrode with a hierarchical porous structure is developed to simultaneously boost the bio- and electro-catalysis for high-performance microbial fuel cells.

Shantanu Bhattacharyya, Srikanta Moharana, Santosh K Satpathy et al.

Journal of Advanced Zoology • 2023

Bio-photovoltaics (BPV) is sustainable energy production technology that utilize photosynthetic organisms and convert it into electricity. This Study has been carried out to study the photosynthetic efficiency of three microalgae on a Reduced Graphene Oxide (RGO) anode surface. RGO, with its exceptional electrical conductivity and large surface area, presents an attractive platform for enhancing the performance of BPV systems. The work aims to investigate the combined effect of microalgae and RGO anodes for use in BPV technology. RGO was synthesized and characterized on which Chlorella vulgaris, Gloeocapsa and Synechocystis were allowed to grow. A model BPV system was assembled, incorporating the microalgae and cyanobacteria as photoactive agents and RGO as the anode surface. The system was subjected to different experimental condition and photosynthetic efficiency, current generation, and power output were collected and analysed. Results demonstrated a significant improvement in the photosynthetic activity of microalgae when cultured on the RGO anode surface. Chlorella Shows maximum Efficiency in terms of growth and current generation. Statistical analysis confirmed the reliability and significance of these findings. Our finding bridges a crucial knowledge gap in the field of BPV, highlighting the potential of microalgae-RGO systems for cleaner energy production.

Aisyah Nadhirah Juhari, Muhd Syazwan Sharani, Wan Ramli Wan Daud et al.

Sains Malaysiana • 2020

A biophotovoltaic cell (BPV) is an electrobiochemical system that utilises a photosynthetic microorganism for instance is algae to trap sunlight energy and convert it into electricity. In this study, a local algae strain, UKM2 Chlorella sp. was grown in a BPV under different trophic conditions and light wavelengths. Once the acclimatisation phase succeeded, and biofilm formed, power generation by UKM2 algae at the autotrophic mode in synthetic Bold’s Basal media (BBM) under white, blue and red lights were tested. Polarisation and power curves were generated at these different conditions to study the bioelectrochemical performance of the system. Later, the condition switched to algal mixotrophic nutritional mode, with palm oil mill effluent (POME) as substrate. Maximum power generation obtained when using UKM2 in BBM under red light where a power density of 1.19 ± 0.16 W/m3 was obtained at 25.74 ± 3.89 A/m3 current density, while the open circuit voltage OCV reached 226.08 ± 8.71 mV. UKM2 in POME under blue light recorded maximum power density of 0.85 ± 0.18 W/m3 at current density of 16.75 ± 3.54 A/m3, while the OCV reached 214.05 ± 23.82 mV. Chemical oxygen demand (COD) removal reached an efficiency of 35.93%, indicating the ability of wastewater treatment and electricity generation in BPV at the same time.

Sadananda Muduli, Rupan Das Chakraborty, Pramod Verma et al.

Journal of The Electrochemical Society • 2022

Lead-carbon hybrid ultracapacitors (Pb-C HUC) are the solution to the sulfation issue of lead-acid batteries. The Pb-C HUCs are of much interest due to the aqueous system with longer cycle life and higher power density. Here, honeycomb structured porous activated carbons with 1790 m 2 g −1 of surface area were synthesized from Carica papaya biowaste by chemical treatment followed by carbonization at 800 °C (PAC-800). PAC-800 composite electrode delivers a specific capacitance of 250 F g −1 at 1 Ag −1 and has 10000 stable cycle life in 4.5 M H 2 SO 4 . Further, a kinetic study of the PAC-800 electrode illustrates that at 2 mV s −1 , they show 61% of capacitive and 39% of pseudocapacitive charge storage. Pb-C HUCs fabricated using in situ activated PbO 2 sheet as cathode and PAC-800 composite electrode as anode delivers 390 F g −1 at 1 A g −1 and have 93% capacitance retention over 15000 cycles at 5 A g −1 . Further, the current Pb-C HUC results are compared with commercially available high surface area (2484 m 2 g −1 ) carbons based Pb-C HUCs. This work illustrates an easy, scalable synthesis root for biowaste carbons and their electrochemical performance in Pb-C HUCs, which is on par with commercial high surface area carbons.

Jiashen Tian, Ryan J. Milcarek

Journal of The Electrochemical Society • 2021

Siloxane, a common contaminant present in biogas, is known for adverse effects on cogeneration prime movers. In this study, the siloxane deposition products and mechanism in the solid oxide fuel cell nickel-yttria stabilized zirconia (Ni-YSZ) anode are investigated analytically and experimentally. An SOFC with Ni-YSZ anode and pure Ni/YSZ pellets were exposed to a simulated biogas-reformate fuel with octamethylcyclotetrasiloxane (D4) contamination at 750 °C. The electrochemical characterization results show that the SOFCs performance degradation caused by D4 contamination is irreversible. Morphology and XRD results illustrate that silicon and carbon deposition can both be detected in the anode and pellets. Graphite, SiC and SiO 2 are all possible products based on the results of XRD test. According to the formation of graphite and SiC, the new mechanism suggests that carbon is also an essential factor in siloxane contamination of Ni-YSZ anodes besides silicon, which can be explained by the catalytic and electrochemical analysis.

Koichi Kasahara, Hirokazu Ishitobi, Shota Yamamori et al.

Journal of Electrochemical Energy Conversion and Storage • 2016

By modifying the carbon electrode with a yeast extract (YE) using a support material (SM), a complete bio-anode was established without adding any extrinsic enzymes and mediators in a glucose–air fuel cell. The yeast extract was mixed into a paste with carbon black and an SM, i.e., glutaraldehyde (GA), TritonX-100, polyethyleneglycol, chitosan, or agarose. Chitosan was the best support, producing lower overpotentials and a good stability. Optimization of the paste composition and its loading were carried out for the bio-anode of a glucose–air fuel cell. The fuel cell generated a power of 33 μW cm−2 at 333 K with an aqueous glucose solution without adding any extrinsic enzymes and mediators. It showed about 70% of the initial power output at a stable condition. The bio-anode is expected to be used for energy recovery from hot wastewater-containing glucose.

Şebnem Cingisiz, Emin Arca, Rezan Demir‐Cakan

ChemElectroChem • 2024

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

Dongling Jia, Jianguo Huang

New Journal of Chemistry • 2017

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

Giulia Massaglia, Adriano Sacco, Angelica Chiodoni et al.

Nanomaterials • 2021

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

En Ren Zhang, Qiang Ji, Lei Liu

Applied Mechanics and Materials • 2012

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

Irene Bavasso, Daniele Montanaro, Elisabetta Petrucci et al.

Sustainability • 2018

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

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

AIMS Bioengineering • 2016

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

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

ACS Nano • 2023

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

Jiaxin Xu, Zhanying Liu, Fang Zhang et al.

RSC Advances • 2020

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

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

ACS Applied Energy Materials • 2020

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

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

Journal of the American Chemical Society • 2025

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

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

International Journal of Energy Research • 2022

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

Zhenzhen Yang, Hongna Li, Na Li et al.

International Journal of Environmental Research and Public Health • 2022

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

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

Dalton Transactions • 2023

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

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

ECS Transactions • 2009

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

Ermete Antolini

Catalysts • 2023

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

Xuejiao Liu, Shixiong Li, Jiantao Zai et al.

Dalton Transactions • 2019

The enormous volume expansion during cycling and poor electron conductivity of SnS 2 limit its cycling stability and high rate capability.

Thomas Tao, Mike Slaney, Linda Bateman et al.

ECS Transactions • 2007

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

Ziyan Zheng, Shaojie Guo, Mengyu Yan et al.

Advanced Materials • 2023

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

Rong Liu, Lina Ma, Gudan Niu et al.

Particle & Particle Systems Characterization • 2017

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

Eric Liese

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

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

Shailesh Kumar Jadhav, Reena Meshram

International Journal of Renewable Energy Development • 2017

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

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

Environmental Engineering Research • 2019

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

Pei Fu, Min Zeng, Qiuwang Wang

Volume 6B: Energy • 2016

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

Tianyun Zhang, Fujuan Wang, Liang Yang et al.

New Journal of Chemistry • 2020

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

Fujuan Wang, Xiaohong Shi, Junlei Zhang et al.

Nanoscale • 2022

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

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

Bulletin of Chemical Reaction Engineering & Catalysis • 2017

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

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

Microorganisms • 2024

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

Agathe Paitier, Naoufel Haddour, Chantal Gondran et al.

Molecules • 2022

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