Bioprocess and biosystems engineering • 2025

Microbial fuel cells (MFCs) have attracted considerable interest as a promising bioelectrochemical technology for directly converting chemical energy into electrical energy. However, their performance remains limited by the properties of anode materials and their interactions with microbial communities. In this study, PPy-MXene/PDA and PDA-PPy-MXene composite hydrogel electrodes (PMP and PPM) were fabricated on a conductive carbon felt substrate to systematically evaluate the influence of different PDA doping strategies on electrode performance. The PMP electrode exhibited a maximum power density of 3.62 W/m 2 , which represented a 34.6% increase compared to the PPM electrode (2.69 W/m 2 ). Moreover, the protein content on the PMP electrode reached 38.05 ± 4.88 mg/cm 2 , 3.79 times higher than that on the PPM electrode (10.05 ± 3.05 mg/cm 2 ). High-throughput sequencing of the 16S rRNA gene revealed that the relative abundance of Geobacter on the PMP electrode surface reached 73.66%, significantly higher than the 51.17% observed on the PPM electrode. These results are attributed to the PDA doping method involving secondary deposition on the electrode surface. This method optimizes the electron transfer pathways and significantly enhances the electrode's conductivity and electrochemical activity by altering the surface roughness of the electrode and increasing the content of hydrophilic functional groups. Consequently, it significantly promotes the enrichment of electroactive microorganisms and improves the efficiency of extracellular electron transfer. This study optimized PDA doping strategies to significantly enhance the electrochemical performance of MFCs, providing new insights and approaches for the rational design of high-performance bioelectrochemical electrodes.

Environmental research • 2025

Exoelectrogenic bacteria (EEB) act as critical drivers in terrestrial and aquatic ecosystems, mediating pivotal biogeochemical processes. However, their low abundance in natural environments poses significant challenges for accurate identification and enrichment. Bioelectrochemical systems (BESs) have emerged as a promising tool for enriching EEB from environmental samples, yet the influence of applied potentials on shaping specific EEB populations remains poorly understood. Here, we developed an effective strategy to selectively enrich targeted exoelectrogenic consortia by adapting anode potentials to the redox conditions of paddy soil. Notably, in BESs inoculated with flooded soil, an applied potential of -0.28 V (simulating the redox conditions dominated by iron oxide-hydroxide reduction) preferentially enriched Geobacter-dominated EEB consortia. Metagenomic functional analysis indicated these EEB were primarily engaged in iron respiration. In contrast, drained soil-inoculated BESs required a higher potential (0.33 V, mimicking nitrate-reducing conditions) for optimal enrichment, resulting in Aeromonas as the predominant genus. The enriched community in this scenario exhibited chemoheterotrophic metabolism and nitrate reduction capabilities. The enrichment dynamics underscore how applied potentials modulate both taxonomic composition and functional specialization of EEB along soil redox gradients, with implications for targeted manipulation of microbial communities for environmental biotechnology applications.

Bioresource technology • 2025

Microbial fuel cells (MFCs), as a green energy technology that simultaneously enables electricity generation and wastewater treatment, exhibit performance that is highly dependent on the structural distribution of the microbial community. In this study, we investigated the effect of magnetic field (MF)-coupled magnetic carbon dots (N-CD/Fe 3 O 4 ) as a selective pressure on the structure of mixed microbial communities in an intermittent pulsating fluidized-bed bioelectrochemical reactor. Under a moderate magnetic field (15 mT), N-CD/Fe 3 O 4 were effectively adsorbed onto microbial cells and subsequently aggregated, significantly enhancing electron transfer within the community. The maximum power density reached 38.43 mW/m 2 , which is about 5.07 times that of the blank control group. 16S rRNA and metagenomic analyses showed that the MF (15 mT) group exhibited significant enrichment of typical electroactive bacteria (40.32 %), such as Geobacter, which directly contributed to improved power production performance. In contrast, under a stronger magnetic field (60 mT), the abundance of typical electroactive bacteria (17.94 %) decreased, while atypical electroactive (38 %) and metabolically complementary bacteria that facilitate syntrophic cooperation (42.85 %) showed adjusted abundances, forming a functionally more balanced microbial community with improved adaptability to real wastewater conditions. This study demonstrates that by tuning magnetic field intensity and coupling with magnetic carbon dots, the structure and function of microbial communities can be directionally regulated, providing an effective strategy for developing electroactive inocula with enhanced power generation and wastewater adaptability.

Journal of hazardous materials • 2025

The widespread existence of tetrabromobisphenol A (TBBPA) in the aquatic environment requires efficient treatment technology. The feasibility and related molecular mechanisms for the simultaneous deep removal of nitrate and TBBPA in a bio-electrochemical system coupled with a constructed wetland (BES-CW) are unclear. This study fabricated the BES-CW to achieve simultaneously deep removal of nitrate and TBBPA. TBBPA majorly went through reductive debromination, hydrolytic debromination, ring-cleavage, and oxidation in the open and closed circuits of BES-CW. Electricity activated key genes encoded in oxidoreductase (pflA, pflX) and oxygenase (dmpB, pobA) from electroactive bacteria (Geobacter and Desulfovibrio), accelerating TBBPA metabolites' oxidation and mineralization. Nitrate enriched the Acinetobacter and stimulated genes encoded in hydrolytic dehalogenase, inducing TBBPA hydrolytic debromination and further mineralization. Electricity and nitrate synergistically enhance TBBPA degradation and mineralization, guiding the advanced treatment of emerging pollutants in the aquatic environment.

Bioresource technology • 2025

Recent studies on bioelectrochemical system (BES) denitrification focus predominantly on removal efficiency and electrode materials, yet a comprehensive understanding of electron transfer mechanisms and process coupling remains lacking. This research critically reviews the key microbial populations, Shewanella and Geobacter, and their dynamic electron transfer pathways. It reveals how electrodes, electron shuttles, and microbial communities establish three-dimensional extracellular electron transfer (EET) networks via cytochromes, nanowires and redox shuttle molecular. This review also evaluates prominent EET enhancement strategies such as the addition of exogenous redox mediators and metal nanoparticles that significantly improve nitrate removal efficiency in laboratory reactors. Additionally, the practical applications of BES in treating nitrogenous wastewater and its integration with other technologies, including groundwater remediation and constructed wetland coupling, are explored. By framing the EET process as a ternary interface of electrodes, mediators, and microbial communities, this review offers a generalized conceptual framework linking EET mechanisms to denitrification performance.

Environmental research • 2025

A denitrifying bio-electrochemical system (BES) with reduced graphene oxide/polypyrrole (rGO/PPy)-modified biocathodes was explored to achieve near-complete nitrate removal at low carbon-to-nitrogen (C/N) ratios (1, 3, and 5). Mechanistic investigations indicated that the rGO/PPy scaffold provided high surface area microbial anchoring sites and mediated efficient electron shuttling between the electrode and biofilm. The conductive 3D rGO/PPy network facilitated direct extracellular electron transfer, eliminating the need for organic carbon supplementation while achieving a maximum power density of 8.2 ± 0.9 mW/m 2 with a coulombic efficiency of 59.1 % at C/N of 5. 16S rRNA sequencing revealed a uniquely balanced consortium dominated by Geobacter (electrogenic), Comamonadaceae (heterotrophic denitrifier), and Thauera (autotrophic denitrifier). Co-occurrence network analysis further demonstrated cross-feeding interactions between these functional groups, enabling concurrent heterotrophic and electrodic autotrophic denitrification pathways. This abiotic-biotic synergy establishes an energy-positive wastewater treatment paradigm, achieving carbon-neutral nitrogen removal with reduced operational costs.

Journal of environmental management • 2025

This study was conducted to explore enhancement of biological anode-dependent ammonium oxidation (bioanoammox) in a bioelectrochemical-enhanced constructed wetland (BECW) by an approach of regulating applied voltage, nitrogen transformation patterns and associated microbiological characteristics of the BECWs were then investigated at four different applied voltages during the advanced treatment of anaerobically-digested swine wastewater. The results showed that, application of different applied voltage could significantly affect start-up and operating performance of the BECW. As the applied voltage was 0.80 V, abundance and activities of the functional microbes (especially Nitrosomonas, Empedobacter, Geobacter, Candidatus Brocadia, and denitrifying bacteria) involved in bioanoammox significantly increased in the anode layer, resulting that the multi-path coupled nitrogen removal process based on bioanoammox was enhanced most effectively on this occasion. Correspondingly, the COD, TP, TN, NH 4 + -N, and NO 3 - -N removal efficiencies of the apparatus, which start-up duration was 25 days, could respectively reach up to (77.01 ± 3.72)%, (94.46 ± 1.96)%, (87.16 ± 2.61)%, (82.87 ± 2.68)%, and (97.27 ± 1.44)% during the stable running phase, as well as the peak current density of (5.29 ± 2.42) A/m 3 and the output power density of 883.51 mW/m 3 . It is concluded that microbial electrochemical driven anaerobic ammonium oxidation could become a primary route for nitrogen removal in the BECW with optimized microenvironment that developed as a result of the appropriate applied voltage.

Environmental science and ecotechnology • 2025

Microbial electrorespiration harnesses bacteria to drive reductive dechlorination, offering a sustainable method to remediate environments contaminated with persistent chlorinated organic pollutants (COPs). However, aquifers' complex hydrogeological and hydrochemical conditions, combined with uneven COP distribution, create substantial spatial and temporal variability in biochemical reactions, environmental factors, and microbial communities. Traditional trial-and-error experiments are labor-intensive and slow, impeding the quick identification of conditions that accelerate dechlorination rates. Here we show that a machine learning framework, integrating experimental design with cathodic biofilm data, uncovers key interrelationships among environmental variables, dechlorination kinetics, electrochemical properties, and functional microbes, enabling rapid optimization of bioelectrodechlorination. Trained on literature-derived datasets using models such as extreme gradient boosting, random forest, and multilayer perceptron, this framework identifies temperature and cathode potential as primary drivers in experimental design while highlighting key biofilm genera, including Clostridium , Desulfovibrio , Dehalococcoides , Pseudomonas , Dehalobacter , Arcobacter , Lactococcus , and Geobacter . It supports inverse design to determine optimal parameters-such as cathode potential, temperature, and additives-for dechlorinating representative COPs, including tetrachloroethene, trichloroethene, and 1,2-dichloroethane, achieving reaction rate predictions with errors below 6 %. This approach surpasses conventional methods by increasing efficiency, cutting costs, and accelerating bioremediation without extensive laboratory testing. By incorporating microbial community insights into predictive models, our data-driven strategy advances the scalable application of microbial electrorespiration for COP-contaminated water remediation and paves the way for broader bioelectrochemical uses in environmental engineering.

Microorganisms • 2025

This work investigated the use of microbial fuel cells (MFCs) for the degradation of polyethylene terephthalate (PET) and the simultaneous generation of electricity. The study implemented two separate single-chamber MFCs, one with a co-culture of Ideonella sakaiensis and Geobacter sulfurreducens (I.S-G.S) and the other with Ideonella sakaiensis and activated sludge (I.S-AS). The effectiveness of microplastic (MP) degradation was assessed based on the electroactivity of the anodic biofilm, the reduction in particle size, and the decrease in PET mass. Both systems achieved a significant reduction in MP size and mass, with the I.S-AS system notably surpassing the I.S-G.S in terms of efficiency and electricity generation. The I.S-AS system achieved a 30% mass reduction and 80% size reduction, along with a peak voltage of 222 mV. The study concludes that MFCs, particularly with the activated sludge co-culture, offer a viable and more environmentally friendly alternative for MP degradation and energy recovery. These findings suggest a promising direction for improving waste management practices and advancing the capabilities of bio-electrochemical systems in addressing plastic pollution. Further research is recommended to optimize the operational conditions and to test a broader range of MP sizes for enhanced degradation efficacy.

Microorganisms • 2025

Aniline aerofloat (AAF) is a typical refractory organic regent residual in mineral processing wastewater (MPW). Microbial fuel cells (MFCs) have been proven highly effective in degrading organic contaminants and resource recovering in wastewater treatment processes. However, AAF biodegradation potential and the related mechanisms in MFC systems remain poorly understood. In this study, the degradation of AAF, electricity generation performance and microbial mechanisms in the single-chamber MFC (sMFC) were confirmed. Affecting factors including AAF concentration, operation resistor, and pH were analyzed. The results indicated that under initial sodium acetate/AAF concentration of 300/100 mg/L, pH 7.0 and an operation resistor of 200 Ω, the AAF removal efficiency achieved 72.7 ± 1.6% with an output voltage of approximately 232 mV. The existence of AAF increased the relative abundance of electroactive bacteria, especially Comamonas and Geobacter . Functional prediction analysis showed that carbohydrate metabolism pathways was the dominant process. The relative abundance of N-respiration and S-respiration functional groups significantly increased, thereby improving COD and AAF removal. This study demonstrated that the MFC anode was beneficial to AAF degradation and provided an alternative route for the biodegradation of organic mineral processing reagents. To our knowledge, this is the first study evaluating AAF biodegradation performance in the MFC system.

Small (Weinheim an der Bergstrasse, Germany) • 2026

Extracellular electron transfer (EET) at the microbe-anode interface remains a critical bottleneck in microbial fuel cells (MFCs). While high-entropy oxides (HEOs) show promise for enhancing anode kinetics, conventional synthesis methods yield poor interfacial integration and fail to elucidate entropy-driven EET mechanisms. Herein, an entropy-engineered bioanode fabricated via ultrafast flash Joule heating (FJH) is reported, which uniformly anchors HEO nanoparticles (Fe─Co─Ni─Cr─Mn─O) onto vertically aligned Fe, N-doped carbon nanotubes grown on carbon cloth (HEO/Fe, N-CNTs/CC). This design synergizes CNT conductivity with HEO pseudocapacitance, achieving a record power density of 3.76 W m -2 , surpassing the state-of-the-art HEO anode by 9.6% and bare carbon cloth by 2.2-fold. The entropy-broadened conduction bands and strengthened cytochrome adsorption (ΔE ads = -3.20 eV) reduce the electron tunneling distance to 2.47 Å, as revealed by DFT calculations. Furthermore, the anode promotes Geobacter enrichment (71% biofilm abundance) and riboflavin secretion, facilitating dual direct and mediated EET pathways. This work establishes entropy modulation as a universal strategy for high-performance bioelectrochemical systems, opening avenues for sustainable energy harvesting and environmental sensing.

ACS applied materials & interfaces • 2025

The low efficiency of extracellular electron transfer (EET) at the bioanode-electrolyte interface remains a critical bottleneck limiting power output and startup kinetics in microbial fuel cells (MFCs). To address this, we developed a biomimetic FeCo bimetallic phthalocyanine/reduced graphene oxide composite anode (FeCo-rGO@CC) inspired by the heme cofactors in cytochrome c . Iron phthalocyanine (FePc) and cobalt phthalocyanine (CoPc) provide atomically dispersed M-N-C active sites analogous to enzymatic centers, synergistically enhancing EET kinetics. Reduced graphene oxide (rGO) serves as a highly conductive scaffold with a large specific surface area, promoting robust electroactive biofilm formation. This integrated design yields improved performance: the FeCo-rGO@CC anode achieves a 43% faster startup (1.03 vs 1.81 days) and a 65% higher maximum power density (3.69 vs 2.23 W/m 2 ) compared to conventional carbon cloth (CC). These significant improvements stem from the anode's ability to enhance bacterial adhesion, enrich electroactive populations, and accelerate interfacial EET. Our work elucidates that the bimetallic Fe/CoN 4 synergy not only mimics but electronically complements the function of c-Cyts, establishing a dual pathway for enhanced direct and mediated electron transfer. This bioinspired strategy of coupling precisely engineered bimetallic active sites with a conductive macroscaffold presents a versatile and effective paradigm for designing high-performance bioanodes in bioelectrochemical systems.

Bioelectrochemistry (Amsterdam, Netherlands) • 2025

Sediment microbial fuel cell (SMFC) is a device for biological denitrification, in which electrons produced by sediment microorganisms can be transferred to the upper layer of the water column lacking electron donors. However, the low efficiency of denitrifying bacteria in acquiring electrons and enriching at the cathode greatly hinders the application of SMFC for nitrogen removal. In this study, we report a novel method of constructing a high-performance biocathode by modifying electrodes with zero-valent iron to enhance the enrichment and electron transfer of electroactive bacteria. The surface chemical and biological analysis of the biocathode revealed that the ZVI gradually oxidized to form magnetite and goethite, and finally stabilized into better crystallized lepidocrocite. On the other hand, the microbial community of the biocathode gradually evolved into a community dominated by denitrifying bacteria, specifically Clostridium. The co-evolved "Clostridium-lepidocrocite" composite endows the sediment microbial fuel cell with a 99% nitrate removal capacity. These results indicate that the cathode constructed by using ZVI modified electrode achieves efficient nitrate reduction by denitrifying bacteria. Furthermore, the construction method of biocathode may also have the potential application in water remediation and the geochemical cycling of elements.

Journal of hazardous materials • 2025

Electronic mediators are an effective means of enhancing the efficiency of microbial electrochemical electron transfer; however, there are still gaps in understanding the strengthening mechanisms and the efficiency of removing antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB). This study systematically elucidates the effects of various electron mediators on bioelectrochemical processes, electron transfer efficiency, and the underlying mechanisms that inhibit ARG propagation within sediment microbial fuel cell systems (SMFCs). The results indicate that the addition of electron mediators significantly increased the output voltage (33.3 %-61.1 %) and maximum power density (14 %-106 %) of SMFCs, while also reducing ARB abundance and transmission risk. The enhancement effect follows the order of biochar, nanoscale zero-valent iron, graphene, and carbon nanotubes, with biochar emerging as the most economical and efficient choice for generating electricity and removing human pathogenic bacteria carrying ARGs. Procrustes analysis revealed that electron mediators facilitated the removal of ARGs by altering the structure of the microbiome, particularly the electricity-generating microorganisms (EGMs). Voltage and mobile genetic elements were the primary drivers of ARGs in the SMFCs. The network analysis results show that multiple carbohydrate-active enzymes, cluster of orthologous groups, and EGMs were negatively correlated with ARGs, indicating that the electron mediator-enhanced SMFCs mainly inhibit the spread of ARGs by promoting cell division, carbohydrate metabolism, and electricity generation. This study provides novel insights into how electron mediators affect ARG removal in microbial electrochemistry, which can inform economically viable strategies for sustainable environmental remediation.

Environmental technology • 2025

The continuous release of phosphorus from sediments by geochemical processes can cause endogenous eutrophication. This study examined the effect of carbon felt-sediment microbial fuel cells (CF-SMFCs) on the release of deposited phosphorus into the overlying water. In the CF-MFC system, the voltage ranged from 27 to 584 mV and the anode electrode potential increased from -130 mV to 202 mV. The Standard Measurements and Testing (SMT) method was employed to sequentially extract the sediment phosphorus in the sediments. A notable vertical increase in NaOH-P and HCl-P concentrations was observed downward in the sediment. The DGT phosphorus, visualized by Zr-Oxide DGT with submillimeter resolution, was removed by 52.04% in CF-SMFC. CF-SMFC notably facilitated the stabilization of phosphorus, promoting its conversion from pore water to sediment. The underlying mechanism suggests that the dissolution of solid-phase phosphorus into the overlying water was mitigated by the competition for organic substrates between Fe(III) reduction and the solid electrode. CF-SMFC can be used to increase the redox potential of the sediment and in-situ stabilize phosphorus in the sediment.

Bioelectrochemistry (Amsterdam, Netherlands) • 2025

Microbial fuel cells (MFCs) generate electricity by converting organic materials and utilizing electroactive bacteria, where anodic biofilms play a vital role in electron transfer and controlling internal resistance. The adaptation of deep-sea microbial communities to diverse environmental conditions, particularly the effects of temperature on biofilm formation and MFC efficiency in high-salinity environments, remains under-explored. This study aims to fill this gap by examining how different temperatures (4 °C (F35), 25 °C (R35), and 37 °C (I35)) affect anodic biofilm formation and MFC performance. The research employs deep-sea sediment inoculum from the South China Sea to enhance understanding of microbial adaptability and optimize performance in extreme conditions. Among the tested conditions, I35 demonstrated the highest current and power densities at 172.49 mA/m 2 and 20.09 mW/m 2 , representing increases of approximately 129 % and 350 % compared to F35. R35 displayed moderate output. Microbial analysis revealed that I35 had the highest CFU count at 7.67 × 10 7  CFU/mL, with Gram staining and colony morphology indicating greater diversity and a higher abundance of electroactive Gram-negative populations at elevated temperatures. Performance improved with increased temperature; however, the power gains were more significant than variations in microbial counts, underscoring the importance of microbial composition, biofilm conductivity, and electron transfer efficiency. Despite having viable bacteria, F35 showed low output due to a less electroactive community and considerable charge transfer resistance. These findings highlight the need to enhance microbial quality, not just quantity, to improve MFC performance in extreme conditions and support the future application of thermally adapted biofilms in high-salinity MFC systems.

Scientific reports • 2026

Self-driven monitoring technique is specifically requested in remote areas. Microbial fuel cell (MFC) was a galvanic cell that has been applied for various environment monitoring. However, MFC is a self-driven probe rather than sensor, since external power was needed for data acquisition. Here, a real self-driven MFC based sensor was developed by using a simplified energy management system (EMS) to enable MFC to power data logger. In this simplified EMS, some common electronics of capacitor, voltage comparator, resistance and trigger switches were removed to reduce power dissipation. As a result, the logger was powered without longtime energy harvesting from MFC. Moreover, since the MFC current generation is changeable with the sampling signal, a rechargeable battery was added as backup power when the current from MFC was too low, or as an energy storage for surplus energy collection other times. Take a dissolved oxygen (DO) sensor as an application example, a MFC was able to detect DO (with a very short energy harvesting time of 10 s), and power logger (with a 1.6% deviation to that with an AC powered Keithley logger), and charge backup battery at the same time, when DO > 5.3 mg/L. When DO < 0.8 mg/L, the power generated from MFC was too low to drive the EMS, and logger was only powered by the rechargeable battery. Besides DO monitoring, this self-driven system may work for other types of MFC sensor as well, such as toxicant sensor, biochemical oxygen demand (BOD) sensor and so on. With a 38$ cost, this self-driven MFC sensor was competitive and attractive for in-situ environment survey.

Environmental technology • 2026

Excessive phosphorus discharge into lacustrine systems was recognized as a primary factor for eutrophication, significantly disrupting the ecological equilibrium of freshwater ecosystems. Effectively controlling endogenous phosphorus release from sediment reservoirs constitutes a fundamental prerequisite for mitigating this environmental challenge. In this study, a sediment microbial fuel cell (SMFC) was developed to address the challenges of sediment-bound phosphorus mobilization. Sediment Total Organic Carbon (TOC) removal in CC-FA-0.2 yielded 2.25 times greater than the control, indicative of aromatic and fulvic acid degradation. Phosphorus in interstitial water decreased by 66% in closed-circuit (CC) reactors, with sequential fractionation revealing enhanced iron-bound phosphorus (BD-P) retention in sediment (105% increase in CC-FA-0.05 vs. versus control). Fe(Ⅲ) redox cycling under SMFC operation maintained higher Fe(Ⅲ) retention (58-54% vs. 51-52% in open-circuit), critical for phosphate immobilization. Microbial profiling identified Proteobacteria (20.41%) and Desulfobacterota (20.41%) as dominant phyla, with genera like Geobacter and Sideroxydans synergistically driving Fe(Ⅲ)/Fe(Ⅱ) cycling and extracellular electron transfer. This study establishes a novel bioelectrochemical strategy based on fulvic-iron synergy, which drive a sustainable electrode-iron-humus redox cycle. This process offers a highly effective and sustainable approach for the simultaneous immobilization of sediment phosphorus and removal of organic pollutants in situ.

ACS omega • 2025

Enhancing bioelectrocatalytic activity to increase the efficiency of toxic compound biodegradation and energy generation continues to be a critical challenge in bioelectrochemical systems. In this context, the present study aimed to obtain a novel electrogenic microbial consortium, sourced from mangrove sediments, capable of improving microbial fuel cell (MFC) performance in both energy generation and aromatic compound's biodegradation. This new microbial consortium was tested in dual-chamber MFCs designed for the biodegradation of benzene, employed as a model aromatic compound. Overall, the results demonstrated that the enrichment of a microbial community derived from mangrove sediments in the southeastern region of Brazil (State of Espírito Santo) significantly enhanced bioelectricity generation in MFCs via benzene biodegradation. During the initial acclimation phase using 1000.0 mg L -1 sodium acetate, the bacterial genera Arcobacter (20.2%) and Comamonas (11.0%) were predominant. As sodium acetate was progressively replaced and the MFC operated solely with benzene (330.0 mg L -1 ), Bacillus (32.9%) and Arcobacter (30.3%) became the dominant genera. The MFC exhibited remarkable efficiency, achieving 98.7 ± 2.4% benzene removal within 96 h, while the output voltage increased from 568.0 ± 10.3 mV to 902.3 ± 20.6 mV as the feedstock shifted from sodium acetate to benzene. The maximum power density, Coulombic efficiency, and MFC cumulative energy efficiency were 390.1 ± 26 mW m -2 , 14.4%, and 17.8%, respectively, surpassing previously established benchmarks and improving power density by approximately 100-fold compared to other devices. In conclusion, this innovative electrogenic microbial consortium, characterized by its unique bacterial diversity, markedly enhanced electron transfer, voltage, power density, and current generation in MFCs. It represents a highly promising and sophisticated approach for both substantial bioelectricity production and the effective bioremediation of aromatics, especially benzene, a compound known for its extreme toxicity, mutagenicity, and carcinogenicity.

Bioelectrochemistry (Amsterdam, Netherlands) • 2026

Sediment resistivity limits the performance of sediment microbial fuel cells (SMFCs) by hindering mass electron transfer in the anodic region. This microcosm study evaluates the effect of bamboo biochar as a conductive additive at different dosages: SMFC-0 (0%), SMFC-0.1 (0.02%), SMFC-1 (0.2%), and SMFC-10 (2%). The study examines the current density, polarization behavior, redox activity, elemental composition, textural properties, anodic biofilm morphology and nutrient removal. The results show that 2% biochar (SMFC-10) increase sediment conductivity by 1.2-fold and reduces ohmic loss for mass electron transfer, achieving the highest power density (26.01 mW/m 2 ) and current output (171 mA/m 2 ). Field emission scanning electron microscopy (FESEM) analysis reveals dense anodic biofilm formation in SMFC-10, supporting higher bioelectricity generation. SMFC-10 improves pollutant removal and mitigates pollutant release into the overlying water, reducing ammonia‑nitrogen (NH 3 -N) from 5 to 1 mg/L and chemical oxygen demand (COD) from 163 to 33 mg/L. High specific BET surface area (430.15 m 2 /g), small pore size (1.62 nm) and high carbon content (79.46%) of biochar contribute to improve performance and long-term stability (165 days) without nutrient replenishment. These findings demonstrate that bamboo biochar is a promising sediment additive to enhance SMFC power generation and water quality.

Microbial cell factories • 2026

This study investigates the potential of microbial fuel cells (MFCs) for bioelectricity generation from seawater and wastewater sources. It focuses on the isolation, identification, and statistical optimization of electrogenic bacteria from diverse environmental samples, aiming to enhance sustainable production of bioenergy.

Frontiers in microbiology • 2025

Lake Towuti, Sulawesi, Indonesia is an ancient tectonic lake, exhibiting iron-rich, sulfate-poor anoxic deep waters. Temporal variations in water column stratification led to sediment accumulation under variable redox conditions. Such ferruginous settings make Lake Towuti an ideal study site to evaluate how a cryptic sulfur cycle could possibly operate under a scarcity of sulfate and abundance of iron minerals, similar to Earth's primitive oceans. Here, we integrate downcore profiles for pore water geochemistry, reactive iron mineralogy, and bulk sediment elemental composition with microbial cell counts, sulfate reduction rates, 16S rRNA genes and metagenomes to resolve microbial sulfur transformations down to 15 m below lake floor (mblf). Sulfate concentrations and reduction rates dropped within the upper mblf, while pore water ferrous iron increased to its highest concentration down to 3 mblf. Any microbially-produced sulfide precipitated as reduced inorganic sulfur in the sediment, apparently forming authigenic millerite (NiS) during burial. The decrease in cell densities tracked the decline in electron acceptors in pore waters with depth. From 3 to 10 mblf, low but sustained sulfate reduction rates were observed with intermittent presence of nitrate in pore water and increased goethite in the sediment, both acting as potential oxidants of sulfur intermediates. A subsequent re-increase in pore water sulfate occurred in parallel with syntrophic fermentation of volatile fatty acids. Consistent with geochemical evolution, the taxonomic diversity of microbial populations shifted from a bacterial assemblage near the surface to selective but prevailing Bathyarchaeia down to 15 mblf. The corresponding metagenome-assembled genomes predicted metabolic potential for complete sulfate reduction ( aprAB , dsrAB ) in Thermodesulfovibrionia, whereas Desulfobacterota (incl. Geobacterales, Desulfuromonadales, Syntrophales) and Aminicenantia exhibited versatility in reducing iron, nitrate ( narG , napA ), nitrite ( nirS , nrfA ) and sulfate ( dsrAB , asrA ). By contrast, Bathyarchaeia were predicted to disproportionate sulfur to polysulfides and reduce ferredoxin via electron bifurcation ( hyd I-II , sudA , dsrC , dsrE ) to fuel a Wood-Ljungdahl pathway, defining homoacetogenesis as terminal electron sink. Together, these mineralogical, geochemical, and metagenomic features provide evidence for a spatially confined but active cryptic sulfur cycle with tight coupling between reduction of mineral ferric iron and intermittent pore water nitrate to syntrophic and lithotrophic (homo)acetogenesis.

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Uchenye Zapiski Kazanskogo Universiteta Seriya Estestvennye Nauki • 2025

Plant microbial fuel cells (PMFC) offer a promising alternative to traditional electricity sources. However, their practical application is limited due to poor electrochemical performance, which is enhanced using various electrode modifications. In this study, MnO2 was electrochemically deposited on the surface of carbon felt and then used as a bifunctional material for the anode and cathode configurations in PMFC systems. The modified carbon felt samples were characterized in terms of electrochemically active surface area and the number of defects determined using cyclic voltammetry and Raman spectroscopy. The resulting density power was 15, 2, and 33 mW/m2 for the control system, PMFC-anode-MnO2, and PMFC-cathodeMnO2, respectively. Thus, the deposition of MnO2 on the cathode in PMFC systems results in a twofold increase of electrical energy generation.

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2025 IEEE International Workshop on Metrology for Industry 4.0 & IoT (MetroInd4.0 & IoT) • 2025

This paper introduces a sustainable IoT framework combining Plant-Microbial Fuel Cells (P-MFCs) and wakeup radio technology within the EcoSentinel project. P-MFCs generate renewable energy from plant-soil-microbe interactions, while wake-up radios enable ultra-low-power communication, addressing energy constraints in environmental monitoring. We evaluate the energy harvested by P-MFCs and the power consumption of wake-up-enabled nodes, demonstrating the feasibility of a self-sustaining sensor network. A tailored communication protocol ensures reliable, event-driven data transmission with minimal energy use. Applications include climate monitoring, precision agriculture, and urban ecology. This work highlights a shift toward bio-integrated, carbon-negative IoT systems, offering eco-friendly solutions for global sustainability. Future efforts will focus on optimizing efficiency and expanding functionality in diverse environments.

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Coatings • 2025

Plant microbial fuel cells (PMFCs) represent an eco-friendly solution for generating clean energy by converting biological processes into electricity. This work presents the first integration of tin sulfide (SnS)-coated 304 stainless steel (SS304) electrodes into Aloe vera-based PMFCs for enhanced energy harvesting. SnS thin films were obtained via chemical bath deposition and screen printing, followed by thermal treatment. X-ray diffraction (XRD) revealed a crystal size of 15 nm, while scanning electron microscopy (SEM) confirmed film thicknesses ranging from 3 to 13.75 µm. Over a 17-week period, SnS-coated SS304 electrodes demonstrated stable performance, with open circuit voltages of 0.6–0.7 V and current densities between 30 and 92 mA/m2, significantly improving power generation compared to uncoated electrodes. Polarization analysis indicated an internal resistance of 150 Ω and a power output of 5.8 mW/m2. Notably, the system successfully charged a 15 F supercapacitor with 8.8 J of stored energy, demonstrating a practical proof-of-concept for powering low-power IoT devices and advancing PMFC applications beyond power generation. Microbial biofilm formation, observed via SEM, contributed to enhanced electron transfer and system stability. These findings highlight the potential of PMFCs as a scalable, cost-effective, and sustainable energy solution suitable for industrial and commercial applications, contributing to the transition toward greener energy systems. These incremental advances demonstrate the potential of combining low-cost electrode materials and energy storage systems for future scalable and sustainable bioenergy solutions.

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

Microbial Cell Factories • 2025

Microalgal biodiesel is a key fossil fuel alternative, but enhancing lipid accumulation via single metabolic gene overexpression is often ineffective. Transcription factor engineering overcomes this by coordinating multiple metabolic pathways. To address the unexplored role of LEC1-type transcription factors in diatoms, we engineered the euryhaline and psychrotolerant biodiesel candidate diatom Phaeodactylum tricornutum through heterologous expression of the key plant lipid regulators AtLEC1 and AtL1L. Codon-optimized genes driven by the endogenous fcpA promoter were integrated into the nuclear genome, with regulators localization confirmed in the nucleus. Crucially, AtL1L transformants exhibited significant redirection of carbon flux from carbohydrates toward lipids, evidenced by lipid content increasing to 29.8%-33.9% of dry weight compared to 20.9% in wild-type controls while carbohydrates decreased to 13.3%-16.5% from 23.1%. AtL1L transformants accumulated 42–64% more neutral lipids and 48–68% higher total fatty acids without compromising biomass yield or photosynthetic efficiency (Fv/Fm). Molecular analyses revealed coordinated upregulation of key lipogenic, glycolytic and pyruvate metabolism genes such as acetyl-CoA carboxylase, pyruvate kinase and malic enzyme, which were corroborated by significant increases in corresponding enzyme activities and NADPH levels. Metabolite profiling confirmed accumulation of lipid precursors including acetyl-CoA (1.7-fold elevation) concurrent with reduction of sugars like glucose to less than 39% of wild-type levels. This study demonstrates the first functional transfer of plant transcription factors to diatoms, providing a transformative strategy for high-productivity microalgal biodiesel.

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The 3rd International Online Conference on Agriculture • 2026

As the global population grows rapidly, effective wastewater management and resource recovery is increasingly critical. Conventional wastewater treatment is energy-intensive, and it increases reliance on fossil fuel supplies. Microbial Electrochemical Systems (MES) offer a sustainable alternative by treating wastewater and producing renewable electricity. This study evaluates a combined MES–hydroponic system facilitating Lactuca sativa growth in cathodes via nutrient transport across a cation exchange membrane (CEM) from municipal wastewater being treated in the anode chamber. The system achieved 56 ± 11% COD removal, 48 ± 21% N removal, 4.32 mW/m 2 peak power density, and a 25% increase in plant wet weight. In contrast, a standard air-cathode cell had 60 ± 15% COD removal, 55 ± 20% N removal, and 0.29 mW/m 2 peak power density. Findings demonstrate the potential of combined MES–hydroponic systems for wastewater treatment and agriculture in a circular economy framework.

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Science and Technology of Engineering, Chemistry and Environmental Protection • 2025

As an important component of the Earth's ecosystem, soil health is directly related to ecological security and human health. In recent years, the combined pollution of heavy metals and microplastics has become increasingly serious, which seriously weakens the ecological function of soil and brings potential health risks. In this paper, typical pollution cases and technical literature are systematically reviewed, focusing on the mechanism of combined pollution of heavy metals and microplastics, to analyze the application efficiency and limitations of bioremediation (Microbial fuel cell, phytoextraction and plant-microbe synergy) and physicochemical remediation (thermal desorption, leaching, solidification-stabilization) technologies. Phytoremediation relies on hyperaccumulators (e.g., pteris vittata) that accumulate arsenic, but is limited by the growth cycle and multitargeting defects. Microbial fuel cells are highly efficient for the degradation of organic pollutants, but are not suitable for large-scale applications. As a carrier of pollutants, microplastics significantly amplify the risk of heavy metal migration, but the existing technology has not yet formed a systematic solution to their synergistic treatment. This study provides a theoretical basis for constructing a soil treatment path of“Pollution removal-ecological function restoration”, and has important practical significance for improving the overall health and sustainable use of soil systems.

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Industrial Biotechnology • 2025

Water scarcity and pollution continue to be crucial challenges globally. By 2030, it is expected that approximately 1.8 billion people will suffer from water scarcity worldwide. Hence, there is a need to shift toward sustainable methods of wastewater treatment, such as hydroponics, which not only treat wastewater but also facilitate the recovery of nutrients like nitrogen and phosphorus, important for crop production. It enables nutrient recovery under controlled environmental conditions, resulting in both crop cultivation and environmental protection. This review highlights the mechanism and effectiveness of hydroponic systems in removing pollutants and nutrients such as nitrogen compounds, phosphates, heavy metals, organic pollutants, and pathogens from wastewater. Additionally, a novel hybrid system of hydroponics-plant-microbial fuel cell has also been proposed for simultaneous wastewater treatment and bioelectricity generation. Further research is required to assess the adaptability of hydroponics wastewater systems on a large scale and to develop agronomic strategies that enhance their efficiency.

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

Jurnal Integrasi Sains dan Qur'an (JISQu) • 2026

The global energy crisis and demand for environmentally friendly energy have driven the development of alternative bioelectrochemical technologies, such as the microbial fuel cell (MFC). This study analyses the effect of soil moisture on the electrical power generated by the MFC system. The research was conducted at Trensains Muhammal High School in Sragen from September to October 2025, using simple linear regression analysis. The analysis shows a regression equation of Y = 1.83 + 0.82X with a coefficient of determination (R²) of 0.994, indicating that 99.4% of the electrical power variability is explained by changes in soil moisture. The regression model was declared valid based on the F test (Fcount = 1258.7; p < 0.05), t test (tcount = 35.48; p < 0.05), and classical assumption tests (p > 0.05). The MFC system can produce 38.2 mW on an area of 100 cm², which is sufficient to power low-power devices. This technology has significant potential for use in sustainable agriculture and achieving SDGs 7 and 13.

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

2025 IEEE International Workshop on Metrology for Industry 4.0 & IoT (MetroInd4.0 & IoT) • 2025

Monitoring plant health is essential for ecosystem stability and sustainable environments. While satellite-based systems like Copernicus support large-scale outdoor vegetation analysis, indoor plants require localized, high-resolution monitoring. This work presents an Indoor Plant Health Monitoring System, designed to assess plant health through a combination of image processing, plant-microbial interaction information and environmental conditions monitoring. The system integrates a high-quality camera with a red-filter lens for Normalized Difference Vegetation Index (NDVI) imaging of the plant, a Plant Microbial Fuel Cell (PMFC) for the potential bioelectricity generation from the plant-microbial activity in the rhizosphere and a soil moisture sensor for humidity monitoring. Experimental results on a Pothos plant demonstrate that the system can detect plant stress early, with PMFC Open Cell Voltage changes occurring 12-24 hours before visible NDVI alterations. The integration of multiple data sources enables detailed insights into plant responses to environmental changes and supports timely interventions.

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

Journal of Advances in Biology &amp; Biotechnology • 2025

Farnesenes are C₁₅ isoprenoids comprising six structurally related α- and β-isomers. These sesquiterpene volatile compounds play a crucial role in plant defense mechanisms and are associated with insect attraction, as well as the development of superficial scald in apples and pears during cold storage. Farnesenes hold substantial economic importance across various industries, including bioenergy, food, cosmetics, and pharmaceuticals. Additionally, they have been recognized as promising alternatives to conventional jet fuels due to their high cetane number, low greenhouse gas emissions, and superior cryogenic properties. Farnesene occurs naturally in several plant species, including rose, rosemary, citrus, apple, cannabis, gardenia, and basil. However, its biosynthesis in plants is inherently limited, yielding insufficient amounts for industrial demands. To address this, metabolic engineering has been used to develop microbial cell factories for farnesene production. Modified microorganisms like Saccharomyces cerevisiae, Escherichia coli, and Pichia pastoris have been engineered to enhance farnesene biosynthesis, providing a sustainable alternative for commercial production.

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

Environmental Quality Management • 2026

The main bottleneck found in microbial fuel cells (MFC) is substrate loss due to unwanted microorganisms, which will reduce the electron transfer and hence coulombic efficiency (CE). Methanogens present in the inoculum competitively inhibit the process of electrogenesis, thereby reducing power output. There are various methods established to inhibit the methanogens or to suppress methane production. Among that, the inhibition methods using medicinal plant metabolites are very prevalent. The allicin compound present in garlic extract is reported to inhibit methanogens and hence can be used as a pretreatment agent, which would enhance the performance of MFC. During long‐term operation, to enrich the electrogens to maintain a stable microbial biofilm and suppress the methanogens, unwanted microorganisms in the anodic inoculum should be removed. The combination of extract pretreatment and inoculum removal strategies has been employed in this study to ensure long‐term improved performance. A significant reduction in the methanogenic population of the anaerobic sludge inoculum could be obtained with garlic extract pretreatment. A maximum CE (20%) and maximum power density (8.4 W/m 3 ) could be obtained while using garlic extract pretreated inoculum in MFC. The CE further improved to 31.7% with the removal of sludge inoculum from the MFC. An increase in bio‐electrochemical activity on the anode was observed during cyclic voltammetry and linear sweep voltammetry after the sludge was removed from the system. In addition, the Congo red dye degradation rate was also found to be enhanced using this strategy, which is found to be sustainable.

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

Journal of Energy Research and Reviews • 2025

This study explores the innovative application of Microbial Fuel Cells (MFCs) for simultaneous treatment and power generation from fertilizer wastewater, addressing the pressing issue of pollution mitigation and renewable energy production. Using urea fertilizer wastewater as a substrate, the research investigates the performance of single- and dual-chamber MFC systems under varying operational conditions. Key parameters, including COD removal efficiency, ammonia and urea reduction, current, and power density, were monitored. Results demonstrate that MFCs can achieve significant treatment efficiencies (COD > 80%, ammonia > 70%) while generating stable power outputs up to 0.66 mA and 0.91 V. The findings highlight the potential of ammonia fertilizer plant effluent as a promising substrate for energy generation in MFCs. This research contributes to the development of sustainable wastewater-energy nexus solutions, enhancing wastewater treatment efficiency and promoting decentralized power generation. The study examines the feasibility, challenges, and scalability of MFC technology for agro-industrial applications, supporting the transition towards circular economy models.

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

Jurnal Presipitasi • 2025

Sustainable domestic wastewater treatment is urgently needed amid water scarcity and rising energy demands. The Constructed Wetland–Microbial Fuel Cell (CW-MFC) system integrates phytoremediation and bioelectricity production by electroactive microorganisms, yet previous studies rarely compared the synergistic effects of different plant species within this system, limiting its optimization. This study evaluated CW-MFC performance using three plant configurations (Pistia stratiotes, Eichhornia crassipes, and their combination) integrated with Lactobacillus plantarum at two concentrations (2×10⁸ CFU/mL and 5×10⁸ CFU/mL). The reactors were operated for 18 days under identical hydraulic conditions to assess BOD, COD, ammonia, and TSS removal efficiencies and power density generation. Results showed that Eichhornia crassipes achieved the highest pollutant removal efficiencies with COD reduction up to 82%, while the system with 2×10⁸ CFU/mL bacterial concentration produced the highest power density of approximately 1032 mW/m². Interestingly, lower bacterial concentrations yielded higher power outputs, possibly due to reduced microbial competition for electron transfer sites, enhancing electroactive bacteria performance. In conclusion, integrating Eichhornia crassipes with L. plantarum at 2×10⁸ CFU/mL optimizes both pollutant removal and bioelectricity production, confirming CW-MFC as an environmentally friendly technology with potential for sustainable wastewater treatment and renewable energy generation. 

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

Environmental Quality Management • 2026

Fish market wastewater has high content of organic pollutants that quickly decompose crustacean and fish residues. This study investigates the performance of sediment microbial fuel cell (SMFC) and plant microbial fuel cell (PMFC) systems where mint plants are used to improve the microbial activity and electricity generation. Over 42 days, both systems were monitored for voltage output, power density, and removal of COD, BOD, oil and grease, and TSS. PMFC delivered a higher peak voltage (181.5 mV) and maximum power density of 25.6 mW/m 2 that was superior to SMFC which delivered 12.8 mW/m 2 and whose voltage decreased after 840 h. Pollutant removal was also superior in PMFC, oil and grease pollutant removal decreased from 2710 to 59 mg/L as compared to 90 mg/L in SMFC. Both systems achieved similar reductions in TSS to below 50 mg/L. Overall, PMFC was shown to be more efficient in wastewater treatment and the bioelectricity production, which promotes its prospects of sustainable wastewater management.

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

BIO Web of Conferences • 2026

Constructed Wetlands and Microbial Fuel Cells represent two promising low-energy technologies for domestic wastewater treatment. Their integration has the potential to enhance both pollutant removal and bioelectricity generation through combined microbial, plant-based, and electrochemical processes. This study evaluated the performance of an integrated CWMFC system operated with two plant configurations, namely the emergent species Equisetum hyemale and the floating species Pistia stratiotes. Five reactor configurations were examined: CW MFC with aeration and bacterial augmentation (CWMFC AB), CW MFC with bacterial augmentation (CWMFC B), CW MFC without augmentation (CWMFC), MFC only system, and CW only system. Each reactor with a volume of 9 liters was operated in batch mode for 18 d using domestic greywater, with monitoring conducted every three days. The CWMFC AB configuration consistently produced the greatest reductions in BOD, COD, and TAN. Emergent plant systems demonstrated stronger TAN removal than floating plant systems. Bioelectricity generation reached a maximum of 794.7 milliwatts per square meter in the emergent CWMFC AB reactor, whereas floating systems produced up to 196.5 milliwatts per square meter. These results indicate that the combined CW MFC approach supported by aeration and Lactobacillus plantarum augmentation, offers an effective strategy for decentralized wastewater treatment and energy recovery.

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

Energies • 2025

Plant Microbial Fuel Cells (PMFCs) represent a promising technology that uses electroactive bacteria to convert the chemical energy in organic matter into electrical energy. The addition of carbon pellet on electrodes may increase the specific surface area for colonization via bacteria. Use of nutrients such as urea could enhance plant growth. Our study aims to address the following questions: (1) Does carbon pellet layering affect the electrical performance of PMFCs? (2) Does urea treatment of the plants used to feed the PMFCs affect the electrical performance? A new prototype of PMFC has been tested: the plant pot is on the top, drainage water percolates to the tub below, containing the Microbial Fuel Cells (MFCs). To evaluate the best layering setup, two groups of MFCs were constructed: a “Double layer” group (with carbon pellet both on the cathode and on the anode), and a “Single layer” group (with graphite only on the cathode). All MFCs were plant-fed by Spathiphyllum lanceifolium L leachate. After one year, each of the previous two sets has been divided into two subsets: one wetted with percolate from plants fertilized with urea, and the other with percolate from unfertilized plants. Open circuit voltage (mV), short circuit peak current, and short circuit current after 5 s (mA) produced values that were measured on a weekly basis. PMFCs characterized by a “Single layer” group performed better than the “Double layer” group most times, in terms of higher and steadier values for voltage and calculated power. Undesirable results regarding urea treatment suggest the use of less concentrated urea solution. The treatment may provide consistency but appears to limit voltage and peak values, particularly in the “Double layer” configuration.

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

2025 IEEE International Workshop on Metrology for Industry 4.0 & IoT (MetroInd4.0 & IoT) • 2025

In the current context of energy transition and sustainability, the need for natural systems capable of generating and managing their own energy is increasingly relevant. This work presents the development of a Green Twin, a digital replica integrated with real-time monitoring systems, to optimize the potential energy generation in a Plant Microbial Fuel Cell (PMFC). The system correlates environmental parameters such as soil moisture, temperature and light intensity, with the bioelectric output generated by a plant and the microbial activity in its rhizosphere. By leveraging environmental sensors and temporal data analysis, the system can identify the optimal conditions in which the PMFC achieves stable and sustainable energy production. A predictive model is established through the analysis of parameter correlations, temporal trends and behavioral rules, enabling the system to anticipate environmental variations and proactively adjust conditions to enhance bioelectrical conversion efficiency. This study proposes a stand-alone implementation of a Green Twin using a Spider Plant (Chlorophytum comosum (Thunb.) Jacques), integrated with an Internet of Everything (IoE) framework to continuously monitor plant status and power generation metrics. The proposed system contributes to the advancement of self-sustaining potential energy generation technologies, with potential applications in agricultural, remote monitoring or ecosystem preservation and conservation, aligning with emerging trends in green technology and ecofriendly electronics.

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

Journal of Qassim University for Science • 2026

The synthesis of luminous metal nanoclusters (MNCs) from natural plant sources is a long-lasting and cost-effective approach to developing improved optical sensors. This thorough study examines the potential of two desert plant species native to the Qassim region of Saudi Arabia as biomediators for the green synthesis of silver nanoclusters (AgNCs) for optical sensing. Desert plants accumulate a wide range of secondary metabolites, such as flavonoids, phenolic compounds, and tannins, that are effective at stabilizing and reducing MNCs. Silver nanoclusters exhibit strong photoluminescence, significant Stokes shifts, and high selectivity for heavy metal ions, making them ideal for building inexpensive, easy-to-use optical sensors. This review brings together what we know about (1) the botanical and phytochemical properties of plant extracts from the Qassim region, (2) the principles and mechanisms of green synthesis of AgNCs using plant extracts, (3) the optical properties and sensing mechanisms of luminescent AgNCs, (4) recent advances in AgNC-based fluorescence sensors for finding toxic metal ions and biomolecules, and (5) the possible scale-up and practical use of plant-derived AgNCs in clinical and environmental settings. The focus is on creating optical sensors that are sensitive, selective, and reversible, with detection limits in the nanomolar range, by employing fluorescence quenching and amplification methods. The combination of traditional ethnobotanical knowledge with current analytical chemistry and nanotechnology demonstrates that it is possible to develop new optical biosensing platforms using plants native to Saudi Arabia.