[object Object], [object Object], [object Object] et al.

Photochemical & Photobiological Sciences • 2021

Photosynthetic purple non-sulfur bacteria (PNB) have been widely utilized as model organisms to study bacterial photosynthesis. More recently, the remarkable resistance of these microorganisms to several metals ions called particular interest. As a result, several research efforts were directed toward clarifying the interactions of metal ions with PNB. The mechanisms of metal ions active uptake and bioabsorption have been studied in detail, unveiling that PNB enable harvesting and removing various toxic ions, thus fostering applications in environmental remediation. Herein, we present the most important achievements in the understanding of intact cell-metal ions interactions and the approaches utilized to study such processes. Following, the application of PNB-metal ions interactions toward metal removal from contaminated environments is presented. Finally, the possible coupling of PNB with abiotic electrodes to obtain biohybrid electrochemical systems is proposed as a sustainable pathway to tune and enhance metal removal and monitoring.

[object Object]

Electrochemistry • 2019

Electrochemical coupling of redox enzyme reactions, called bioelectrocatalysis, has been attracting great attention over the last four decades. It has become an important technology that can be applied to a wide range of bioelectrochemical devices including biosensors, biofuel cells, and bioreactors. This article presents an overview of the basic concepts of steady-state catalytic waves of mediated- and direct electron transfer (DET)-type bioelectrocatalysis. Several equations that can be used for the analysis of steady-state waves are introduced. The analysis may provide important thermodynamic and kinetic parameters that can be used not only for performance evaluation of the devices but also for fundamental research on the enzymes. Important progress made on how to tune electrode surfaces and enzymes for DET-type reactions are presented. Applications to bioelectrochemical devices are also summarized with emphasis on the achievements recorded in our research group.

[object Object], [object Object], [object Object] et al.

Biosensors • 2024

Extremozymes combine high specificity and sensitivity with the ability to withstand extreme operational conditions. This work presents an overview of extremozymes that show potential for environmental monitoring devices and outlines the latest advances in biosensors utilizing these unique molecules. The characteristics of various extremozymes described so far are presented, underlining their stability and operational conditions that make them attractive for biosensing. The biosensor design is discussed based on the detection of photosynthesis-inhibiting herbicides as a case study. Several biosensors for the detection of pesticides, heavy metals, and phenols are presented in more detail to highlight interesting substrate specificity, applications or immobilization methods. Compared to mesophilic enzymes, the integration of extremozymes in biosensors faces additional challenges related to lower availability and high production costs. The use of extremozymes in biosensing does not parallel their success in industrial applications. In recent years, the "collection" of recognition elements was enriched by extremozymes with interesting selectivity and by thermostable chimeras. The perspectives for biosensor development are exciting, considering also the progress in genetic editing for the oriented immobilization of enzymes, efficient folding, and better electron transport. Stability, production costs and immobilization at sensing interfaces must be improved to encourage wider applications of extremozymes in biosensors.

[object Object], [object Object], [object Object] et al.

Bioresource Technology • 2016

[object Object], [object Object], [object Object] et al.

Nature Communications • 2025

extraction kinetics of the APIP increased by a remarkable 2.9-fold owing to the evaporative convection and photothermal effects. Collectively, APIP overcomes the application key limitations of powdered LISs, and opens new avenues for seawater utilization and the advancement of the Sustainable Development Goals.

[object Object], [object Object], [object Object] et al.

ACS Applied Energy Materials • 2018

Harvesting the energy generated by photosynthetic organisms through light-dependent reactions is a significant step toward a sustainable future energy supply. Thylakoid membranes are the site of photosynthesis, and thus particularly suited for developing photo-bioelectrochemical cells. Novel electrode materials and geometries could potentially improve the efficiency of energy harvesting using thylakoid membranes. For commercial applications, electrodes with large surface areas are needed. Photolithographic patterning of a photoresist, followed by pyrolysis, is a flexible and fast approach for the fabrication of carbon electrodes with tailored properties. In this work, electrode chips consisting of patterned carbon supported on quartz were designed and fabricated. The patterned electrode area is 1 cm2, and the measurement chamber footprint is 0.5 cm2, 1 order of magnitude larger than previously tested electrodes for thylakoid membrane immobilization. The use of a transparent substrate allows back-side illumination, protecting the bioelectrochemical system from the environment and vice versa. Two different mediators, monomeric ([Ru(NH3)6]3+) and polymeric ([Os(2,2′-bipyridine)2-poly(N-vinylimidazole)10Cl]+/2+), are used for evaluating photocurrent generation from thylakoid membranes with different electrode geometries. Current densities up to 71 μA cm–2 are measured upon illumination through the transparent electrode chip with solar simulated irradiance (1000 W m–2).

[object Object], [object Object], [object Object] et al.

Advanced Functional Materials • 2015

before transferring them to the electrode, creating a photobioelectrochemical system in which a redox protein is used to mimic the efficient charge separation found in biological photosystems.

[object Object], [object Object], [object Object] et al.

Bioprocess and Biosystems Engineering • 2025

The purpose of this review is to gain attention about intro the advanced and green technology that has dual action for both clean wastewater and produce energy. Water scarcity and the continuous energy crisis have arisen as major worldwide concerns, requiring the creation of ecologically friendly and sustainable energy alternatives. The rapid exhaustion of fossil resources needs the development of alternative energy sources that reduce carbon emissions while maintaining ecological balance. Microbial fuel cells (MFCs) provide a viable option by producing power from the oxidation of organic and biodegradable chemicals using microorganisms as natural catalysts. This technology has sparked widespread attention due to its combined potential to cleanse wastewater and recover energy. The review presents a complete examination of current advances in MFCs technology, with a focus on the crucial role of anode materials in improving their performance. Moreover, different anode materials and their nanoscale modifications are being studied to boost MFC efficiency. This current review also focused on the effects of surface modifications and different anode compositions on power generation and system stability. It also investigates the electrochemical principles behind these enhancements, providing insights into the economic potential of MFCs. MFCs provide a long-term solution to energy and environmental issues by addressing both wastewater treatment and energy production.

[object Object], [object Object], [object Object] et al.

Environmental Science Advances • 2024

Synthesis of regenerable chitosan-embedded magnetic iron oxide beads.

[object Object], [object Object], [object Object]

Microorganisms • 2019

, ash free dry weight (AFDW), and dry weight (DW) were measured to assess phototrophic and whole biofilm biomass development over time. From the analysis of photosynthetic parameter variation with light intensity, temperature and flow rate, it was possible to identify the set of experimental values favoring biofilm photosynthetic activity. Biomass increased over time, especially at the highest irradiances, where substrata were fastly colonized and mature biofilms developed at all temperatures and flow conditions tested.

[object Object], [object Object], [object Object] et al.

Polish Journal of Environmental Studies • 2018

Constructed wetlands have been extensively applied for treating drinking water sources and other water bodies that are not severely polluted due to their low construction and operation costs. In this regard, microbial fuel cells (MFC) could potentially achieve both energy generation and wastewater purification, though the construction cost is high. Based on the bio-electrochemical theory, a novel device of the integrated vertical flow constructed wetland (IVCW) embedded with MFC (IVCW-MFC) was designed and built for treating the slightly-polluted source waters with relatively high nitrogen and low carbon, where denitrification was usually hindered. Both water purification performance and electrical characteristics were examined in this system. It was observed that the maximum output voltage and power density could reach 777 mV and 8.05 mWm -2 , respectively, when the external resistance was 6000 . With a better denitrification effect, the system exhibited a more effective removal of chemical oxygen demand (COD) and nitrate. The maximum efficiency of total nitrogen (TN) removal was as high as 97.35%, while the average removal efficiency was around 70%, even with a load of TN, 3.3 mg/L on average, in the influent. Furthermore, the macrophytes grew normally in the constructed wetland without any influence.

[object Object], [object Object], [object Object] et al.

Reviews in Agricultural Science • 2018

Denitrification, which converts soil nitrogen to nitrogen gas, involves a great loss of nitrogen fertilizer. Controlling the process of denitrification rate could help reducing the losses of applied nitrogen fertilizer in crop fields. Fertilizer nitrogen is one of the major concerns due to the high energy demand for its production. Since flooded rice soils are known to have strong denitrifying activity, innovative techniques are emerging as needs to improve nitrogen fertilizer retention efficiency in flooded rice soils. Nitrous oxide (N2O) emissions are not considered as significant, compared to that of methane (CH4) emissions from flooded rice soils, most probably due to its complete denitrification process with prolonged submergence that favors the production of nitrogen (N2) gas. This is due to a further reduction of N2O to N2. However, efficient use of nitrogen in the rice soils could have the benefits of saving energy costs that are being spent on nitrogen fertilizers in many developing countries. While conventional approaches are less efficient in controlling denitrification, technical solutions are emerging to solve this need. Technical solutions based on soil redox potential (Eh) for the control of denitrification have not been adequately covered. We propose that applicability of microbial fuel cell based on soil redox chemistry would be more promising for the control of denitrification in flooded rice soils.

[object Object], [object Object], [object Object] et al.

Sustainable Energy Technologies and Assessments • 2021

[object Object], [object Object], [object Object] et al.

Journal of Power Sources • 2018

[object Object], [object Object], [object Object] et al.

Organic Electronics • 2017

[object Object], [object Object], [object Object] et al.

iScience • 2024

This review highlights the application of biochar (BC) for attaining different SDGs (SDG 6: clean water and sanitation, SDG 7: affordable and clean energy, SDG 13: climate action, and SDG 15: life on land). These goals coincide with the various existing environmental problems including wastewater treatment, soil amendment, greenhouse gas remediation, and bioenergy generation. So, the review encompasses the various mechanisms involved in the BC-assisted treatment and reclamation of water, pollutant immobilization and enhancing soil properties, reduction of greenhouse gas emission during the wastewater treatment process and soil amendment mechanisms, bioenergy generation through various electrode material, biodiesel production, and many more. The review also explains the various drawbacks and limitations of BC application to the available environmental issues. Conclusively, it was apprehended that BC is an appropriate material for several environmental applications. More research interventions are further required to analyze the applicability of different BC materials for attaining other available SDGs.

[object Object], [object Object], [object Object] et al.

ACS Sustainable Chemistry & Engineering • 2020

Efficient depolymerization of lignocellulosic biomass is a prerequisite for sugar production and its subsequent upgradation to fuels and chemicals. Organic carbonate solvents, i.e., propylene carbonate (PC), ethylene carbonate (EC), and dimethyl carbonate (DMC), which are low in toxicity and biodegradable, were investigated as “green” co-solvents (PC/H2O, EC/H2O, DMC/H2O, solvent ratio 1:1) for depolymerization of cellulosic paper towel waste. PC/H2O and EC/H2O enhanced the depolymerization of paper towel waste and improved the total sugar yield (up to ∼25 C mol %) compared to H2O only (up to ∼11 C mol %) under mild reaction conditions (130 °C, 20 min). The higher performance of PC/H2O and EC/H2O can be attributed to higher availability of reactive protons in the catalytic system that facilitates efficient acid hydrolysis of recalcitrant cellulosic fibers. Moreover, a substantial buildup of in-vessel pressure by CO2 release during the microwave-assisted reaction because of decomposition of PC or EC might have accelerated the conversion of paper towel wastes. PC and EC are prospective solvents for lignocellulosic biomass conversion considering their green features and notable catalytic performance, which have a good potential for substituting conventional organic solvents such as dimethyl sulfoxide (DMSO) and tetrahydrofuran (THF) that are often considered hazardous in terms of health, safety, and environmental implications.

[object Object], [object Object], [object Object] et al.

Fuel • 2022

[object Object], [object Object], [object Object] et al.

Electrochimica Acta • 2018

[object Object], [object Object], [object Object] et al.

Environmental Pollution • 2022

[object Object], [object Object], [object Object] et al.

IEEE Access • 2022

Low Power Wide Area Networks (LPWAN) have emerged as an appealing IoT communication solution. Large coverage and low power consumption are critical requirements when deploying a communication network to support an IoT application. Despite the fact that existing LPWAN technology solutions promote IoT requirements such as long communication range, energy efficiency, scalability, and low cost, there are numerous concerns about the performance of this type of communication network. With a wide range of LPWAN technologies available, there is growing interest in their evaluation. This paper proposes an experimental comparative evaluation based on coverage and energy-efficiency test performance for LoRaWAN and SigFox, two emerging LPWAN technologies operating in sub-GHz Industrial, Scientific, and Medical (ISM) frequency bands. Recent works have presented various comparison studies of LPWAN technologies, however most of them have been tackled from the perspective of comparing their technical specifications without presenting measurement results obtained from network deployment scenarios. We argue that by proposing a comparative evaluation from an experimental perspective, the comparison discussion is taken to the next level. The experimental evaluation has been proposed first by selecting coverage and energy-efficiency as the most significant design goals for LPWAN applications. Second, by proposing the test performance to evaluate those goals, where extensive measurements are made in network deployments, and finally, by highlighting the main findings about performance for both network for comparison purposes. Results show that in a test with fair conditions LoRaWAN performed better than SigFox in an urban environment in terms of coverage, obtaining a better packet delivery rate (PDR ≳ 80%) with higher radio strength signal (RSSI ≳ - 110 dBm). Whereas Sigfox shows better energy efficiency with a 20 % of more sent messages under the same test conditions.

[object Object], [object Object], [object Object] et al.

Limnetica • 2019

Lake La Cruz is considered a biogeochemical analogue to early Earth marine environments because its water column is depleted in sulfate, but rich in methane and iron, similar to conditions envisaged for much of the Precambrian. Here we show that conductive particles drove the metabolic coupling between electroactive microbial clades from this environment. The anoxic sediment of Lake La Cruz was rich in biogeochemically 'reactive' iron minerals, and harbored known electroactive species such as Geobacter and Methanothrix, in addition to groups never linked to an electroactive lifestyle. Slurry incubations on various substrates in the presence of conductive particles showed 2 to 4 times higher methanogenic activity, as compared to incubations with non-conductive glass beads or without added particles. In the absence of conductive particles, all tested substrates were metabolized to acetate, which accumulated above 8 mM depending on substrate (80.6 to 11.71.2 mM). Only by enabling syntrophic acetate oxidation with conductive minerals could we prevent acetate accumulation. Acetate oxidation conductively coupled to methanogenic activity had a stoichiometric recovery of 70 % and could be maintained in subsequent transfers only if amended with conductive particles. Mud-free enrichments without conductive particles ceased any metabolic activity after the second transfer. Conductive particles preserved a consortium of Youngiibacter-Methanothrix, whereas without conductive particles Youngiibacter spp. died off. Syntrophic consortia from this early Earth analogue environment only survived in the presence of conductive particles inferring that minerals may have arbitrated the earliest interspecies associations.

[object Object], [object Object], [object Object] et al.

Malaysian Journal of Science and Advanced Technology • 2024

Water irrigation remain as a challenge to supply adequate amount of water to sustain the growth of plant and crops yield along the year in certain part of the world which are heavily affected by climate change. This scenario creates a huge risk toward the world food supply chain. Hence, the application of smart farming system is crucially important now to pave the way for a better the agriculture monitoring system to replace traditional manual monitoring labour by farmers. The smart farming system are usually equipped with environmental stimuli sensing system such as temperature, humidity, soil moisture, light intensity sensing sensors coupled with automation actuators to control the water irrigation rate for the crops in order to save water and at the same time provide adequate water supply for plant growth. The aim of using such smart farming system is to enable higher crops production and less human labour at the same time optimising resources available to minimize cost of farming. Hence, this paper aims to introduce a novel approach of a Raspberry Pi powered IoT smart farming system (ISFS) which can incorporate autonomous monitoring of plant irrigation, temperature, humidity, soil moisture and light intensity, to design a smartphone app that allows users to monitor plantation-related conditions in a user-friendly manner, and to enable automatic control of a drip irrigation system for plants based on data obtained on soil moisture, temperature and sunlight intensity. The proposed prototype with the functionality mentioned is aim to resolve the existing problem and to meet the demand of smart farming application in current era.

[object Object], [object Object], [object Object] et al.

Sustainability • 2023

This bibliometric review elucidates the emerging intersection of Internet of Things (IoT) technologies and Green Stormwater Infrastructure (GSI), demonstrating the potential to reshape urban stormwater management. The study analyzes a steadily increasing corpus of literature since 2013, pointing out considerable international collaboration. Prominent contributions originate from the United States, Canada, Italy, China, and Australia, underscoring the global acknowledgement of the potential of IoT-enhanced GSI. Diverse GSI applications such as green roofs, smart rain barrels, bioretention systems, and stormwater detention ponds have demonstrated enhanced efficiency and real-time control with IoT integration. However, existing literature reveals several challenges, notably the requirement of advanced monitoring, the development of predictive optimization strategies, and extensive scalability. Comprehensive cost–benefit analyses are also critical for the widespread acceptance of IoT-integrated GSI. Current research addresses these challenges by exploring innovative strategies such as microbial-fuel-cell-powered soil moisture sensors and large-scale RTC bioretention systems. Emphasis is also on the need for security measures against potential digital threats. Future research needs to focus on real-time data-based monitoring plans, model validation, continuous optimization, and supportive policy frameworks. As the world confronts urban development, climate change, and aging infrastructure, IoT and GSI synergism presents a promising solution for effective stormwater management and enhancement of cultural ecosystem services. Continued exploration in this promising domain is crucial to pave the way for smarter, greener urban environments.

[object Object], [object Object], [object Object] et al.

Advanced Energy Materials • 2019

Abstract Semiartificial photosynthetic systems have opened up new avenues for harvesting solar energy using natural photosynthetic materials in combination with synthetic components. This work reports a new, semiartificial system for solar energy conversion that synergistically combines photoreactions in a purple bacterial photosynthetic membrane with those in three types of transition metal–semiconductor Schottky junctions. A transparent film of a common transition metal interfaced with an n‐doped silicon semiconductor exhibits an in‐plane potential gradient when a light‐penetration variance is established on its surface by optical shading of photoabsorbing photosynthetic membranes. The in‐plane potential gradients (0.08–0.3 V) enable a directional charge transport between the synthetic and natural photoelectric systems, which is further enhanced in a device setting by a biocompatible thixotropic gel electrolyte that permeates the membrane multilayer, facilitating a strong and steady photoelectric current as high as 1.3 mA cm −2 , the highest achieved so far with any anoxygenic photosynthetic system.

[object Object], [object Object], [object Object] et al.

TrAC Trends in Analytical Chemistry • 2020

[object Object], [object Object], [object Object] et al.

Scientific Reports • 2021

Denitrification is an important part of the nitrogen cycle and the key step to removal of nitrogen in surface-flow wetlands. In this study, we explored space-time analysis with high-throughput sequencing to elucidate the relationships between denitrifying bacteria community structures and environmental factors during different seasons. Our results showed that along the flow direction of different processing units, there were dynamic changes in physical and chemical indicators. The bacterial abundance indexes (ACEs) in May, August, and October were 686.8, 686.8, and 996.2, respectively, whereas the Shannon-Weiner indexes were 3.718, 4.303, and 4.432, respectively. Along the flow direction, the denitrifying bacterial abundance initially increased and then decreased subsequently during the same months, although diversity tended to increase. The abundance showed similar changes during the different months. Surface flow wetlands mainly contained the following denitrifying bacteria genus: unclassified Bacteria (37.12%), unclassified Proteobacteria (18.16%), Dechloromonas (16.21%), unranked environmental samples (12.51%), unclassified Betaproteobacteria (9.73%), unclassified Rhodocyclaceae (2.14%), and Rhodanobacter (1.51%). During different seasons, the same unit showed alternating changes, and during the same season, bacterial community structures were influenced by the second genus proportion in different processing units. ACEs were strongly correlated with temperature, dissolved oxygen, and pH. Bacterial diversity was strongly correlated with temperature, electrical conductivity, pH, and oxidation reduction potential. Denitrifying bacteria are greatly affected by environmental factors such as temperature and pH.

[object Object], [object Object], [object Object] et al.

Ecosystem Health and Sustainability • 2017

ABSTRACT Introduction: Plant communities and soil factors might interact with each other in different temporal and spatial scales, which can influence the patterns and processes of the wetland ecosystem. To get a better understanding of the distribution of plants in wetlands and analyze their associations with environmental soil factors, the structure and types of plant communities in the eastern shore area of Lake Taihu were analyzed by two-way indicator species analysis and canonical correspondence analysis (CCA) ordination. The spatial distribution patterns of vegetation and the main factors affecting the distributions were investigated. Outcomes: Sixty-six sampling sites were selected to obtain vegetation species and soil environmental factor data. Results showed that 22 species from the 66 sites could be divided into seven communities: I: Arundo donax ; II: A. donax + Phragmites australis ; III: Zizania latifolia + Typha orientalis ; IV: P. australis + Alternanthera philoxeroides + Polygonum hydropiper ; V: P. australis ; VI: P. australis + Humulus scandens ; and VII: Erigeron acer + Ipomoea batatas + Rumex acetosa . Plant species and soil factors in the CCA analysis showed that I. batatas , E. acer, Chenopodium album, Polygonum lapathifolium , and Acalypha australis were mainly affected by pH, whereas Echinochloa crus-galli , Setaria viridis , and H. scandens were mainly affected by soil total phosphorus. Mentha canadensis and A. donax were mainly affected by soil conductivity, A. philoxeroides was mainly affected by soil organic matter and, Z. latifolia, Metaplexis japonica and P. hydropiper were mainly affected by available phosphorus. Conclusion: These results indicated that different plants adapted to different soil environmental factors and provided basic information on the diversity of Lake Taihu wetland vegetation.

[object Object], [object Object], [object Object] et al.

Journal of Polymers and the Environment • 2023

Abstract Production of bacterial cellulose hydrogel and its evaluation as a proton exchange membrane (PEM) was evaluated. Initially, the bacterial cellulose hydrogel membranes (BCH) was produced by fermentation in a 600 mL bioreactor with a 300 mL medium volume, 10% v/v inoculum with Komagataeibacter hansenii under static conditions, and a temperature of 30 °C. The bacteria were cultivated in Hestrin-Schramm (HS) medium with pH adjustment to 6.6 with HCl and/or NaOH. Five culture media were evaluated to obtain uniformity on the surface and a rapid formation of BCH membrane: HS (M1), M1 + green tea extract (M3), M1 + mixture of extra thyme and green tea (M4), and M1 + glycerin (M5). The kinetics of BCH production was followed by digital images. Subsequently, BCH production cellulose was carried out using M5 under the same operating conditions. After 3, 5, 10 and 13 days of fermentation, the thickness of BCH formed was measured, respectively, as 0.301 ± 0.008 cm, 0.552 ± 0.026 cm, 0.584 ± 0.03 cm and 0.591 ± 0.018 cm. Finally, BCH was characterized by porosity, water absorption capacity, ion exchange capacity, mechanical strength and diffusivity. The results showed that thinner membranes favor the processes of ion exchange (0.143 H + mmol g −1 ) and water absorption (93%). On the other hand, thicker membranes enhance physical parameters of transport across the membrane and its operability. Nevertheless, BCH membranes can be a good alternative as PEM to microbial fuel cell once they are functionalized.

[object Object], [object Object], [object Object] et al.

Nature Communications • 2015

Photosynthetic reaction centres show promise for biomolecular electronics as nanoscale solar-powered batteries and molecular diodes that are amenable to atomic-level re-engineering. In this work the mechanism of electron conduction across the highly tractable Rhodobacter sphaeroides reaction centre is characterized by conductive atomic force microscopy. We find, using engineered proteins of known structure, that only one of the two cofactor wires connecting the positive and negative termini of this reaction centre is capable of conducting unidirectional current under a suitably oriented bias, irrespective of the magnitude of the bias or the applied force at the tunnelling junction. This behaviour, strong functional asymmetry in a largely symmetrical protein-cofactor matrix, recapitulates the strong functional asymmetry characteristic of natural photochemical charge separation, but it is surprising given that the stimulus for electron flow is simply an externally applied bias. Reasons for the electrical resistance displayed by the so-called B-wire of cofactors are explored.

[object Object], [object Object], [object Object]

Frontiers in Plant Science • 2023

transportation in an open pond system can be saved. In this context, the present review outlines the bottlenecks of first- and second-generation biofuels along with the conventional algae cultivation systems such as open ponds and photobioreactors. Furthermore, it discusses about the process sustainability and efficiency of integrating algae cultivation with MFC technology in detail.

[object Object], [object Object], [object Object] et al.

Energy & Environmental Science • 2016

The finding of cytochrome complexes in the external matrix of electricity producing biofilms supports the proposal of a new functional model, in which electrons expelled by cells are conducted to the collecting electrode along a redox network interconnected by semiconducting pilus fibres.

[object Object], [object Object], [object Object]

Water Resources Research • 2020

Abstract Molecular diffusion of dissolved species is a fundamental mass transport process affecting many environmental and technical processes. Whereas diffusive transport of single tracers can be described by Fick's law, a multicomponent approach based on the Nernst‐Planck equation is required for charge‐coupled transport of ions. The numerical solution of the Nernst‐Planck equation requires special attention with regard to properties that are required at interfaces of numerical cells when using a finite difference or finite volume method. Weighted arithmetic and harmonic averages are used in most codes that can solve the Nernst‐Planck equation. This way of averaging is correct for diffusion coefficients but inappropriate for solute concentrations at interfaces. This averaging approach leads to charge balance problems and thus to numerical instabilities near interfaces separating grid volumes with contrasting properties. We argue that a logarithmic‐differential average should be used. Here this result is generalized, and it is demonstrated that it generally leads to improved numerical stability and accuracy of concentrations computed near material interfaces. It is particularly relevant when modeling semipermeable clay membranes or membranes used in water treatment processes.

[object Object], [object Object], [object Object] et al.

Bioelectrochemistry • 2023

[object Object], [object Object], [object Object] et al.

ACS Sustainable Chemistry & Engineering • 2019

The development of new technologies that use sunlight as an energy source is adding to pressure on finite natural resources and the challenges of recycling and disposal. Looking to nature for material assistance, we describe a proof-of-concept flexible and biodegradable photoelectrochemical cell based almost entirely on pigments, proteins, polysaccharides, and graphene platelets. In addition to being largely environmentally benign, such devices present opportunities for the recovery of valuable components such as, in the present case, the geologically scarce metal indium and the precious metal gold. Recovery is achieved through dissolution in ethanol followed by physical separation of the heavy element, leaving a residue made up from common elements that can be recycled through natural biodegradation. Potential applications for flexible, biomolecule-based photoelectrochemical cells are considered.

[object Object], [object Object], [object Object]

Journal of Water Process Engineering • 2023

Excess unmanaged nitrogen pollutes the environment. A sustainable wastewater treatment system must achieve better pollutant removal efficiency at a lower cost, and the feasibility of integrating biological nitrogen removal into bio-electrochemical systems (BES) has been reported as a tool in green technology. Nitrogen in the form of nitrate (NO3) is a common pollutant in both surface and ground waters, and a high level of NO3 makes water unsuitable for drinking water. This analysis and review of BES for treating NO3 polluted water investigate BES's components and operational factors and their importance on the NO3 removal efficiency to design more powerful but economic systems. The NO3 removal efficiencies were analyzed by the influence of electrode materials, working mode, number of chambers, type of inoculum, capacity, and microbial community structure. Overall, the electrode materials, significantly influence the NO3 removal rate. The operational parameters, such as working mode, the number of chambers, inoculum type and the systems' capacity, were deemed important and have significantly influenced the NO3 removal efficiencies when analyzed by the random forest classification algorithm. Proteobacteria and Firmicute were the prominent phyla observed in BES treating NO3 polluted water. Besides the denitrification (abundance of narG, nirS, nirK, nosZI, and nosZII genes) process in BES, there is evidence of electrochemical support for anaerobic ammonium oxidation (ANAMMOX) (abundance of hzsB or ANAMMOX-specific 16S rRNA genes) and dissimilatory NO3 reduction to ammonium (DNRA) (abundance of nrfA genes) processes. Our analysis suggest that BES, as a continuous two-chamber system with cathode and anode materials as granular carbon and carbon paper, respectively, with denitrifying microbes as inoculum type, would contribute to optimum NO3 removal efficiencies.

[object Object], [object Object], [object Object] et al.

The Science of The Total Environment • 2022

[object Object], [object Object], [object Object]

Current Opinion in Colloid & Interface Science • 2022

Electrochemical impedance spectroscopy (EIS) is a powerful probe of the processes taking place at an electrode. Depending on frequency, it is sensitive to the solid-liquid interface as well as to processes taking place in the solution further from the electrode. In principle, shrinking electrode dimensions allows probing these processes on the nanometer scale. In practice, however, this represents a formidable challenge. Signals resulting from the stray capacitance of the interconnects can dramatically exceed those from the electrode itself. Furthermore, miniaturized electrodes exhibit faster dynamics, and thus necessitate working at higher frequencies in order to achieve comparable performance. Here we discuss recent advances in nanoscale impedance measurements. We begin with a theoretical discussion of the main concepts and inherent tradeoffs, followed by a review of recent experimental efforts. As this field remains in its infancy, we place particular emphasis on the conceptual and technical aspects of the approaches being developed.

[object Object], [object Object], [object Object] et al.

Journal of Hazardous Materials • 2023

[object Object]

Materials research foundations • 2023

Day by day, the energy demand is exceeding due to consumption by increasing world population and fast-growing industrialization. As a result, the biggest problems of the 21st century are energy demand and how it affects the environment. The disquiet is caused by the excessive reliance on fossil fuels as raw materials for the production of energy, such as coal, oil, and natural gas. Around 13 terawatts of energy are needed every day by more than 6.5 billion people around the world. However, the scarcity of currently used fossil fuels and the environmental deterioration corresponding to fuel rectification processes have triggered the compulsion to produce renewable, non-polluting, and eco-friendly energy generation and conversion technologies. Suitable technologies for the conversion and storage of energy will play a vital role in addressing the current challenges associated with the increasing demand for clean, renewable, sustainable, transferable, benign, eco-friendly, nominal, and ceaseless power supplies for users. The substitution of fossil fuels could be clean energies, for example, solar, hydroelectric, wind, geothermal, biogas, and tidal energies. Generally, alternative renewable energy conversion requires various complicated physical and chemical processes on the surface and interfaces of cell components and transporting electrons, positive holes, ions, and molecules through the entire system. The harnessing of energy requires new and novel nanomaterials and evolution of nanocomposite and multifunctional nanostructured materials, including metal, ceramic, polymer matrix, and amalgamation. Various essential advantages of using engineered nanomaterials, such as high surface area, unique physicochemical properties, mechanical strength, and favorable transport properties, are crucial to energy harnessing applications. Electrocatalysis-based energy conversion devices are widely studied to get high yield and optimum performance of energy conversion services. The structural engineering of nanomaterials is associated with the fabrication of size, spatial array, hetero architecture, and shape of nanostructures, thereby producing a well-defined novel nanomaterial, which could be used for high-performance energy conversion system applications. The development and the innovations introduced in nanotechnology and material chemistry are making key breakthroughs for amplifying these devices' performance for perceiving the objective of renewable and sustainable clean energy technologies. The engineered nanomaterials such as nanoparticles, nanorods, nanospheres, nanosheets, nanotubes, and nanowires have drawn the attention of many nanotechnologists because of their attractive physical and chemical properties attributed to their significantly smaller size. The applications of zero (0-), one (1-), two (2-), and three (3-) dimensional nanostructures in the construction of high performance and cost-effective systems for harnessing energy by using renewable and sustainable technologies have been reported in many works of literature. This chapter will focus on the basic characteristics and idea of engineered nanomaterials for energy conversion cells with well-built prominence on the connection between structural features and resultant performances. In addition to emphasizing the applications of various nanomaterials in energy conversion cells, the apparent advantages, disadvantages, limitations, and challenges will be addressed. Finally, the outlook regarding the prospective futures of engineered nanomaterials for energy conversion will be discussed.