Robert Hren, Annamaria Vujanović, Yee Van Fan et al.

Renewable and Sustainable Energy Reviews • 2022

Hydrogen applications range from an energy carrier to a feedstock producing bulk and other chemicals and as an essential reactant in various industrial applications. However, the sustainability of hydrogen production, storage and transport are neither unquestionable nor equal. Hydrogen is produced from natural gas, biogas, aluminium, acid gas, biomass, electrolytic water splitting and others; a total of eleven sources were investigated in this work. The environmental impact of hydrogen production, storage and transport is evaluated in terms of greenhouse gas and energy footprints, acidification, eutrophication, human toxicity potential, and eco-cost. Different electricity mixes and energy footprint accounting approaches, supported by sensitivity analysis, are conducted for a comprehensive overview. H2 produced from acid gas is identified as the production route with the highest eco-benefit (−41,188 €/t H2), while the biomass gasification method incurred the highest eco-cost (11,259 €/t H2). The water electrolysis method shows a net positive energy footprint (60.32 GJ/t H2), suggesting that more energy is used than produced. Considering the operating footprint of storage, and transportation, gaseous hydrogen transported via a pipeline is a better alternative from an environmental point of view, and with a lower energy footprint (38 %–85%) than the other options. Storage and transport (without construction) could have accounted for around 35.5% of the total GHG footprint of a hydrogen value chain (production, storage, transportation and losses) if liquefied and transported via road transport instead of a pipeline. The identified results propose which technologies are less burdensome to the environment.

Myrto‐Panagiota Zacharof

Waste and Biomass Valorization • 2016

Grape wine is among the most important alcoholic beverages in the globe, with a continuously rising world demand, currently sizing at 25 billion litres. Such a large and heavily industrialised market calls for the maintenance of a steady production of raw materials to end products. Consequently, intensive cultivation of land, harvesting of the goods and manufacturing for the production of commercially available products are being implemented. Wine making is a timed, multistage process producing a large amount of organic and inorganic waste. It has been calculated that during cultivation and harvesting about 5 tonnes of solid waste are generated per hectare per year, while the winery wastewater varies according to the production size from 650,000 m3 (Greece) to over 18,000,000 m3 (Spain) per year. Conventional treatments of winery waste are becoming increasingly expensive, demanding significant amounts of effort, resources and energy for safe waste discharge. Therefore, the need to recycle, reuse and recover energy and valuable chemicals from winery waste and wastewater becomes apparent. Valorisation of winery waste is possible when introducing the concept of biorefinery, i.e. the use of winery waste as bioconversions feedstock in order to produce platform chemicals, biofuels, heat and energy.

Mebrahtu Hagos Kahsay

National Academic Digital Repository of Ethiopia • 2019

The release of brewery wastewater sludge with high pollutants and soluble organic contents can pose a significant threat to human health and environment due to their toxicity. The present study aims at investigating the potential of Microbial Fuel Cell (MFC) to utilize brewery wastewater sludge as feed stock of electricity generation. The characterization of the brewery wastewater sludge before and after it goes through the microbial fuel cell was analyzed using reactor digestion method, OxiTop BOD5, (HACH method DR890) molybdovanadate method, (HACH method DR 890) TNT per-sulfate digestion method for chemical oxygen demand (COD), biological oxygen demand (BOD), total nitrogen (TN), and total phosphorus (TP) respectively. The effect of varying salt concentrations (1 M, 2M, and 3M) of the salt bridge in MFC have been analyzed with different factors like temperature ranging 20 to 45 °C, and pH ranging from 4 to 10. Results were analyzed in terms of efficiency in chemical oxygen demand (COD), biological oxygen demand (BOD5), total nitrogen (TN), and total phosphorus (TP) removal and capability of energy generation. The optimum temperature was found 32.5 °C, with the optimum pH of 7 and 3 M salt bridge concentration in which the maximum removal percentage and power generation was observed. At the optimum condition the observed power output, removal percentage of chemical oxygen demand (COD), biological oxygen demand (BOD5), total nitrogen (TN), and total phosphorus (TP) were 0.88 V, 93.58%, 93.07%, 1.39%, and 1.19% respectively. Box-Behnken experimental design (BBD) has been used to find the optimum condition for voltage production, chemical oxygen demand (COD), biological oxygen demand (BOD5), total nitrogen (TN), and total phosphorus (TP) removal percentage.

Getachew Bantihun, Andualem Mekonnen, Seid Mohammed et al.

Environmental Technology & Innovation • 2025

Potentially useful species, electrogenicbacteria are used as sustainable anode biocatalysts to produce green energy and in wastewater management. Here, this study aims to identify and characterize electrogenic bacteria from six wastewater and one soil samples. Double chambered microbial fuel cell (MFC) system was designed to develop anode biofilm. Bio-electrochemical property of electrogenic bacteria isolates (EBIs) were characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and observation of biofilm on the anode using scanning electron microscope (SEM). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and 16S rRNA gene sequencing was performed for identification. From a total of 72 biofilm forming EBIs, MALDI-TOF-MS identified 21 selected EBIS, including Aeromons, Bacillus, Citrobacter, Pseudomonas and Raoultella genus . This is the first study to characterize Enterococcus species from real brewery sludge waste, using the 16S rRNA sequencing. Evolutionary history analysis, GC content (53.72 %) and sequence alignment profiles infer this isolate as the first time report with biocatalyst potential. The evolutionary history for EBIs was found to be Enterococcus species and designated as E. faecium strain BSE14. The isolate showed biologically stable for long term operation of MFC (0.46 ± 0.038 V) with chemical oxygen demand (COD) (95.4 ± 0.82 %), biological oxygen demand (BOD) (53.3 ± 0.531 %), total nitrogen (TN) (73.1 ± 0.674) and total phosphorus (TP) (44.8 ± 0.281). Voltage generation among unknown mixed and pure EBIs exhibited significant variation (df=6, p < 0.05 and df=7, p < 0.05, respectively). Finally, the EBIs contribute as a potential biocatalyst in energy generation and wastewater treatment applications . • Wastewater was potential hosting environment for electrogenic bacteria. • 16S rRNA analysis revealed a biocatalyst Enterococcus species for MFC application. • Isolated spp. showed active metabolic process in electron transfer & biodegradation. • The electrogenic isolates showed 95.4 % of COD removal efficiency of wastewater. • Use of electrogenic bacteria for wastewater treatment is promising and low cost.

Barbara Włodarczyk, Paweł P. Włodarczyk

Energies • 2026

The increasing generation of industrial wastewater necessitates sustainable treatment strategies combined with resource recovery. Brewery wastewater, characterized by high organic content and low toxicity, represents a promising substrate for bio-electrochemical systems such as microbial fuel cells (MFCs). This study evaluates the feasibility of electricity generation from wastewater originating from a small-scale research brewery using a dual-chamber glass MFC equipped with a carbon felt anode and a foamed-glass separator. The system was operated in a repeated fed-batch mode over six consecutive 100 h cycles, with fresh wastewater supplied when the cell voltage decreased to 60% of its maximum value. Stable electrochemical performance was observed, with an average cell voltage of 304 mV and a maximum power density of 24 mW·m−2. A consistent decrease in COD concentration of approximately 8.66% per 100 h operational cycle was recorded, along with a 4.93% reduction in NO3− concentration, while NH4+ levels remained largely unchanged. The results indicate that brewery wastewater from small-scale facilities can support sustained bio-electrochemical activity under simplified, non-optimized conditions. Although power output and contaminant concentration changes were limited, the study provides a laboratory-scale study and highlights the need for further optimization of reactor configuration and operational parameters.

Shaoqin Liu, Jinzhi Sun, Ruiwen Wang et al.

SSRN Electronic Journal • 2023

Dawn E. Holmes, Pravin Malla Shrestha, David J. F. Walker et al.

Applied and Environmental Microbiology • 2017

The possibility that Methanothrix (formerly Methanosaeta ) and Geobacter species cooperate via direct interspecies electron transfer (DIET) in terrestrial methanogenic environments was investigated in rice paddy soils. Genes with high sequence similarity to the gene for the PilA pilin monomer of the electrically conductive pili (e-pili) of Geobacter sulfurreducens accounted for over half of the PilA gene sequences in metagenomic libraries and 42% of the mRNA transcripts in RNA sequencing (RNA-seq) libraries. This abundance of e-pilin genes and transcripts is significant because e-pili can serve as conduits for DIET. Most of the e-pilin genes and transcripts were affiliated with Geobacter species, but sequences most closely related to putative e-pilin genes from genera such as Desulfobacterium , Deferribacter , Geoalkalibacter , and Desulfobacula , were also detected. Approximately 17% of all metagenomic and metatranscriptomic bacterial sequences clustered with Geobacter species, and the finding that Geobacter spp. were actively transcribing growth-related genes indicated that they were metabolically active in the soils. Genes coding for e-pilin were among the most highly transcribed Geobacter genes. In addition, homologs of genes encoding OmcS, a c -type cytochrome associated with the e-pili of G. sulfurreducens and required for DIET, were also highly expressed in the soils. Methanothrix species in the soils highly expressed genes for enzymes involved in the reduction of carbon dioxide to methane. DIET is the only electron donor known to support CO 2 reduction in Methanothrix Thus, these results are consistent with a model in which Geobacter species were providing electrons to Methanothrix species for methane production through electrical connections of e-pili. IMPORTANCE Methanothrix species are some of the most important microbial contributors to global methane production, but surprisingly little is known about their physiology and ecology. The possibility that DIET is a source of electrons for Methanothrix in methanogenic rice paddy soils is important because it demonstrates that the contribution that Methanothrix makes to methane production in terrestrial environments may extend beyond the conversion of acetate to methane. Furthermore, defined coculture studies have suggested that when Methanothrix species receive some of their energy from DIET, they grow faster than when acetate is their sole energy source. Thus, Methanothrix growth and metabolism in methanogenic soils may be faster and more robust than generally considered. The results also suggest that the reason that Geobacter species are repeatedly found to be among the most metabolically active microorganisms in methanogenic soils is that they grow syntrophically in cooperation with Methanothrix spp., and possibly other methanogens, via DIET.

Jinzhi Sun, Ruiwen Wang, Huidong Li et al.

Materials Today Energy • 2023

Khaya Pearlman Shabangu, Babatunde Femi Bakare, Joseph K. Bwapwa

Water • 2022

An evaluation of a laboratory scale chemical coagulation using aluminium chlorohydrate (1%) and polyamine (1%) coagulants on its effectiveness in the removal of bulk inert pollutant contents such as particulate chemical oxygen demand (COD) and turbidity to obtain clean effluent discharge and most cost-effectively treated effluent using a jar test was conducted in this current study. This study aimed to find the viable inert removal coagulant between the two above-mentioned coagulants in order to achieve zero liquid effluent discharge (ZLED). The preliminary results showed that adding variable dosages of polyamine and 50% aluminium chlorohydrate combined coagulants dosages presented an improved particulate chemical oxygen demand, color, and turbidity removal efficiencies. The ascertained turbidity removal efficiency using the combined coagulation dosage of polyamine–aluminium chlorohydrate (PAC) treatment was 90.50% and 59.36% particulate chemcial oxygen demand removal, as comparable to polyamine alone with particulate chemical oxygen demand removal of 50% and turbidity of 75%. Likewise, an appreciable removal efficacy was observed as the aluminium chlorohydrate treatment alone was for particulate chemical oxygen demand and turbidity was 37% and 54%, respectively. In essence, this study emphasized the knowledge gap of the significant effect of the polymeric polyamine flocculant strength in adopting the combined coagulation dosage method to improve its coagulation efficiency and the high agglomeration on suspended solids, thereby, removing more of the unwanted inert contents from brewery wastewater. To determine zero liquid effluent discharge, this study clearly recommended an integrated treatment approach, microbial fuel cell integrated with a lab scale chemical coagulation technique for efficient non-biodegradable pollutant removal.

Somil Thakur, Rajnish Kaur Calay, Mohamad Y. Mustafa et al.

Current Research in Biotechnology • 2025

• Substrates and their constituents are the most important factor for consideration in on-field MFC operations as it determines overall power production, microbial growth, and metabolic activity. • Accurate identification and measurement of constituents in Municipal wastewater facilitates proper pretreatment for subsequent use in MFCs. • As a product of fermentation processes, brewery wastewater requires relatively less hydraulic retention time for effective MFC operation. Microbial Fuel Cells (MFC) have emerged as a potential wastewater treatment technology that utilizes metabolic processes of microorganisms present in the wastewater to disintegrate organic substrates and harness direct electricity. This paper reviews the potential of different wastewater types as a suitable substrate for microbial activities in MFCs. Substrate composition (carbon source, nutrient content and inhibitory compounds) directly affects the microbial growth, wastewater treatment potential, electron transfer rate and power harvested. Readily biodegradable substrates such as acetate and glucose promote microbial metabolism and electron transport, thus resulting in enhanced power generation. Substrates such as municipal or agricultural wastewater that constitute both simple and complex organic matter require longer breakdown durations but can provide MFCs with long term operational stability. On the other hand, substrates such as leachate from landfills, mining wastewater etc. are generally unsuitable for regular operations. The paper discusses the challenges such as suitability of various wastewaters, unpredictability of composition, presence of inhibitory chemicals like heavy metals or toxic organics that can subdue the microbial activity and reduce efficiency of a MFC reactor. It aims to identify the relationship between the substrate characteristics and MFC performance in order to select the substrate for achieving optimal output from MFC technology. The suitable substrates that exhibit optimal performance in terms of current and power output, coulombic efficiency, and reduction in chemical oxygen demand are identified.

Joshua Marks, Johan Kirkel, Patrick T. Sekoai et al.

Environmental and Climate Technologies • 2020

Abstract In recent years, fuel cells have become a renewable source of energy. Among different kinds of fuel cells, microbial fuel cells, which convert organic substrates to electricity by electrogenic bacteria have attracted most attention. In this study, which is preliminary in nature, potential of electricity generation and chemical oxygen demand (COD) removal were studied in a two-chamber microbial fuel cell (MFC) reactor. Effect of type of feedstock and inoculum source on bioelectricity generation and COD removal was studied as well. Brewery wastewater and potato waste were used as substrates while anaerobic sludge and cow dung were used as inoculum sources. The substrate and inoculum sources were in 8.2:1 ratio and a phosphate buffer was added to the anode compartment to regulate the pH. The system was operated at 30 °C and a home-made membrane served as a bridge between the electrodes. A maximum voltage of 3.6 mV was generated from the brewery wastewater sludge and the maximum COD removal after 3 days was 43.7 %. It was further found that the use of animal dung as inoculum source outperformed the use of sludge as regard the bioelectricity generation but not for COD removal. Similarly, the use of the brewery waste as an organic substrate outperformed the use of potato waste as regard the bioelectricity generation but not for COD removal. All experiments yielded a measurable voltage, however, the unsteady behaviour of the voltage output made it difficult to compare substrates in terms of their viability as organic fuel. Therefore, future studies should consider conducting substrate physico-chemical analysis and genomic analysis of the inoculum sources to understand their composition.

Jiadong Liu, Chang Tian, Xiaolan Jia et al.

Biochemical Engineering Journal • 2017

Gustavo Silveira, Sidney de Aquino Neto, José Maurício Schneedorf

Energy • 2020

Gregory Lui, Gaopeng Jiang, Michael Fowler et al.

Journal of Power Sources • 2019

Emile Tabu Ojong, S. Brunschweiger, Karl Glas et al.

Chemie Ingenieur Technik • 2018

Tegen Dagnew Tessema, Temesgen Atnafu Yemata

International Journal of Energy Research • 2022

In recent decades, shortage and crisis of energy being a serious issue of concern all over the world as the fossil fuel reserves have been diminishing. A particular emphasis has been given for bio-energy harvesting from waste and cellulosic biomass by employing an efficient conversion system. Among these, microbial fuel cell (MFC) systems are an emerging promising technology for the effective wastewater treatment. However, the collective effect of waste substrates, inoculum composition, and catholyte concentrations on the performance of MFC system remains unclear. Hence, this study aimed to investigate the effect of electron acceptors under different set of parameters in response to its electrochemical performance inoculum chemical oxygen demand (COD) concentration and type of the electron acceptor on the performance of the electrochemical has been studied. A dual-chamber MFC with 0.4 to 0.6 M values of potassium permanganate (KMnO4) and Ferricyanide K3[Fe(CN)6], (900-2520 mgL−1) of COD values, and oxygen as a control substance were used. The experiments were carried out in a batch mode for 20 days of operation. The results reveal that MFC with 0.4 M KMnO4 provides an external output voltage of 310.09 ± 0.06 mV and external output power density value of 400.4 ± 0.46 mWm−2 while 0.4 M K3[Fe(CN)6] results an external output voltage of 252.18 ± 0.12 mV and an external output power density value of 380.28 ± 0.24 mWm−2. Analysis of variance was done using central composite design approach to support the significance of each experimental factors on the responses and the result shows that the confidence interval of 95% for all the parameters that were statistically significant.

O. D. Akinwumi, M. O. Aremu, S. E. Agarry

Biomass Conversion and Biorefinery • 2022

Tegen Dagnew Tessema, Temesgen Atnafu Yemata

Data in Brief • 2021

This research data set contains data related to experimental dataset on the effect of the electron acceptors in energy generation from brewery wastewater via a microbial fuel cell. The presented data gives information on the generation of electricity and waste minimization as various electron acceptors adopted in microbial fuel cells. Dual-chamber microbial fuel cell (MFC) system was assembled with aluminium mesh electrode as an anode and sulfonated tetrafluoroethylene membrane for proton exchange as a cathode at 500-2000 mg/L chemical oxygen demand (COD). A 0.4 and 0.6 M of Potassium permanganate (KMnO 4 ) and potassium cyanide K 3 [Fe(CN) 6 were used anaerobically as a mediator for electron acceptor in the cathode chamber. Furher more, The pH, COD, total nitrogen, biochemical oxygen demand, total phosphorous, total suspended solid and electrical conductivity for the raw brewery wastewater were measured. Inaddition, the voltage generated and the current density have been obtained for both (KMnO 4 ) and K 3 [Fe(CN) 6 electron acceptors. Moreover, the COD removal efficiency, Columbic efficiency, voltage generation, current, and power density were measured.

S. Brunschweiger, Emile Tabu Ojong, Jana Weißer et al.

Bioresource Technology Reports • 2020

Fengfei Sun, Junfeng Chen, Ziren Sun et al.

The Science of The Total Environment • 2024

Alex J.T. Harewood, Srinivasa R. Popuri, Elon I. Cadogan et al.

International Journal of Environmental Science and Technology • 2017

Lalise Wadajo Negassa, Majid Mohiuddin, Girum Ayalneh Tiruye

Journal of Water Process Engineering • 2021

Ayesha Kausar, Ishaq Ahmad, Tingkai Zhao et al.

Crystals • 2023

Among nanocomposite materials, multifunctional polymer nanocomposites have prompted important innovations in the field of sensing technology. Polymer-based nanocomposites have been successfully utilized to design high-tech sensors. Thus, conductive, thermoplast, or elastomeric, as well as natural polymers have been applied. Carbon nanoparticles as well as inorganic nanoparticles, such as metal nanoparticles or metal oxides, have reinforced polymer matrices for sensor fabrication. The sensing features and performances rely on the interactions between the nanocomposites and analytes like gases, ions, chemicals, biological species, and others. The multifunctional nanocomposite-derived sensors possess superior durability, electrical conductivity, sensitivity, selectivity, and responsiveness, compared with neat polymers and other nanomaterials. Due to the importance of polymeric nanocomposite for sensors, this novel overview has been expanded, focusing on nanocomposites based on conductive/non-conductive polymers filled with the nanocarbon/inorganic nanofillers. To the best of our knowledge, this article is innovative in its framework and the literature covered regarding the design, features, physical properties, and the sensing potential of multifunctional nanomaterials. Explicitly, the nanocomposites have been assessed for their strain-sensing, gas-sensing, bio-sensing, and chemical-sensing applications. Here, analyte recognition by nanocomposite sensors have been found to rely on factors such as nanocomposite design, polymer type, nanofiller type, nanofiller content, matrix–nanofiller interactions, interface effects, and processing method used. In addition, the interactions between a nanocomposite and analyte molecules are defined by high sensitivity, selectivity, and response time, as well as the sensing mechanism of the sensors. All these factors have led to the high-tech sensing applications of advanced nanocomposite-based sensors. In the future, comprehensive attempts regarding the innovative design, sensing mechanism, and the performance of progressive multifunctional nanocomposites may lead to better the strain-sensing, gas/ion-sensing, and chemical-sensing of analyte species for technical purposes.

Aisha A. Alshahrani, Laila S. Alqarni, Maha D. Alghamdi et al.

Heliyon • 2024

The aqueous onion peel extract (OPE) was used to synthesize silver nanoparticles (Ag-onion), samarium oxide nanoparticles (Sm 2 O 3 -onion), and silver/samarium oxide core/shell nanoparticles (Ag@Sm 2 O 3 -onion). The produced nanoparticles were characterized by thermal gravimetric analysis (TGA), infrared spectra (FT-IR), absorption spectra (UV-Vis), energy band gap, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), zeta potential, and transmission electron microscopy (TEM). OPE and NPs were tested for the disinfection of some water microbes. XRD analysis exhibited an amorphous structure of samarium oxide in both Sm 2 O 3 -onion and Ag@ Sm 2 O 3 -onion. The isolated bacteria from the water sample were Bacillus subtilis (OQ073500) and Escherichia coli (MW534699), while the isolated fungi were Alternaria brassicae (MZ266540), Aspergillus flavus (MT550030), Aspergillus penicillioides (MW957971), Pythium ultimum (MW830915), Verticillium dahlia (MW830379), Fusarium acuminatum (MZ266538), Candida albicans (MW534712), and Candida parapsilosis (MW960416). High levels of antimicrobial activity were seen in both the nanoparticles and the aqueous onion peel extract. Based on experimental results, Ag@Sm 2 O 3 demonstrated the highest activity as an effective disinfectant, indicating the effectiveness of the modification process.

Jin-Beom Kwon, Yuntae Ha, Suji Choi et al.

Scientific Reports • 2024

The global industrial development and increase in the number of transportation vehicles, such as automobiles and ships, have led to a steady increase in the issues related to greenhouse gas emissions. NO 2 is a greenhouse gas emitted in large quantities from automobiles and factories, and its emission is unavoidable in the modern world. Therefore, a sensor capable of precise detection of NO 2 is required. The most commonly reported types of NO 2 sensors are those based on metal oxides. However, their operation at room temperature is impossible owing to their high-temperature operating characteristics, and therefore, a heater must be designed inside or installed outside the sensor for heating. Meanwhile, NO 2 sensors based on PbS quantum dots (QDs) are advantageous as they can operate at room temperature and can be easily manufactured through a solution process rather than a complicated semiconductor process. Herein, a NO 2 sensor was fabricated by doping PbS QDs with poly(3-hexylthiophene) (P3HT). The as-developed sensor exhibited high responsivity to 100-0.4-ppm NO 2 gas with a resolution of 200 ppb owing to the stability of the thin film and high hole mobility of P3HT.

He Zhang, Weigen Chen, Yanqiong Li et al.

Frontiers in Chemistry • 2018

Acetylene gas (C 2 H 2 ) is one of the main arc discharge characteristic gases dissolved in power transformer oil. It is of great potential to monitor the fault gas on-line by applying gas sensor technology. In this paper, gas sensors based on nanorods and nanoneedles assembled hierarchical NiO structures have been prepared. Herein, we focus on investigate the relationship between the sizes of the assembling blocking units and gas sensing properties. It can be found that the addition of CTAB/EG plays a vital role in controlling the sizes of blocking unit and assembly manner of 3D hierarchical structures. A comparison study reveals that an enhanced gas sensing performance toward C 2 H 2 for the sensor based on nanoneedle-assembled NiO flowers occurs over that of nanorod-assembled NiO. This enhancement could be ascribed to the larger specific area of needle-flower, which provides more adsorption and desorption sites for chemical reaction as well as effective diffusion channels for C 2 H 2 . Besides, a method of calculating the specific surface area without BET testing was presented to verify the results of gas sensing measurement. The possible growth mechanism and gas sensing mechanism were discussed. Such a synthesis way may open up an avenue to tailor the morphologies and control the sizes of blocking units of some other metal oxides and enhance their gas sensing performances.

Vijaykiran N. Narwade, Rajendra S. Khairnar, Vanja Kokol

Cellulose • 2017

Phenol removal from aqueous medium was studied by the batch method using novel and fully biobased solvent-cast films prepared from cellulose nanofibrils (CNFs) and in situ synthesised hydroxyapatite (HAp) by the wet-chemical precipitation method and different concentrations of HAp precursors and weight mass of CNFs. The chemical and morphological structures of as-prepared films were investigated by X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy, while their physical properties were determined by water contact angle and swelling kinetic measurements. The HAp precursor leads to a surface modification of CNFs, which increases its activity by forming differently structured, sized and distributed HAp particles, influencing the phenol adsorption kinetic and capacity. The phenol adsorption was faster and higher (~64 mg g−1) in an acidic solution (pH 2) compared to the original phenol solution pH (pH 7.4, ~30 mg g−1) using films with unevenly-distributed and positively-charged calcium-richer HAp particles synthesised on the CNFs’ surface, being reflected also in its higher water swelling properties, compared to their hybrid counterparts. The phenol adsorption is identified to follow pseudo-second order kinetic and intra-particle diffusion models. A highly-efficient reusing ability of the selected film with 86% adsorption capacity of the initial value at the third sequential regeneration cycle, is also confirmed. A super-hydrophilic nature of the films with high water-diffusing and transport properties, as well as low swelling, indicates their potential in the development of highly-effective adsorbents and, potentially, filter membranes for water purification.

Supachok Tanpichai

eXPRESS Polymer Letters • 2021

Since last decades, nanocellulose has gained much attention in nanocomposite foams owing to high stiffness and strength, renewability, sustainability and biodegradability. Nanocellulose is hydrophilic, and could be easily dispersed in hydrophilic polymer matrices; however, there are challenges to introduce nanocellulose in less hydrophilic polymers. This review addresses the development of polymer nanocomposite foams with plant-based nanocellulose (cellulose nanofibers and cellulose nanocrystals), and the chemical modification and mechanical approaches to enhance the dispersibility of nanocellulose in hydrophobic polymer matrices. The combination of nanocellulose and other nanoparticles such as graphene nanoplatelets, montmorillonite clay, carbon nanotubes and zeolites to yield multifunctional porous nanocomposite materials with promising features such as self-extinguishment, dye adsorption, microwave absorption, conductivity and biocompatibility is also discussed in this paper.

Hossein Jafari Mansoorian, Amirhossein Mahvi, Ramin Nabizadeh et al.

Journal of Environmental Health Science and Engineering • 2020

H. M. Araújo, Biljana Šljukić, Sandra Gago et al.

Frontiers in Energy Research • 2024

Climate change is showing its impacts now more than ever. The intense use of fossil fuels and the resulting CO 2 emissions are mainly to blame, accentuating the need to develop further the available energy conversion and storage technologies, which are regarded as effective solutions to maximize the use of intermittent renewable energy sources and reduce global CO 2 emissions. This work comprehensively overviews the most recent progress and trends in the use of transition metal-based electrocatalysts for three crucial reactions in electrochemical energy conversion and storage, namely, the oxygen evolution (OER), oxygen reduction (ORR), and hydrogen evolution (HER) reactions. By analyzing the state-of-the-art polyoxometalates (POMs) and metal-organic frameworks (MOFs), the performance of these two promising types of materials for OER, ORR, and HER is compared to that of more traditional transition metal oxides and alloy-based electrocatalysts. Both catalytic activity and stability are highly influenced by the adsorption energies of the intermediate species formed in each reaction, which are very sensitive to changes in the microstructure and chemical microenvironment. POMs and MOFs allow these aspects to be easily modified to fine-tune the catalytic performances. Therefore, their chemical tunability and versatility make it possible to tailor such properties to obtain higher electrocatalytic activities, or even to obtain derived materials with more compelling properties towards these reactions.

Shahira H. EL‐Moslamy, Mohamed Elnouby, Ahmed H. Rezk et al.

Scientific Reports • 2023

In this study, we identified a suitable precursor and good cellular compartmentalization for enhancing bioactive metabolites to produce biosynthetic zinc oxide nanoparticles (ZnO NPs). An effective medium for cultivating endophytic Streptomyces albus strain E56 was selected using several optimized approaches in order to maximize the yield of biosynthetic ZnO NPs. The highest biosynthetic ZnO NPs yield (4.63 g/L) was obtained when pipetting the mixed cell-free fractions with 100 mM of zinc sulfate as a precursor. The generation of biosynthetic ZnO NPs was quickly verified using a colored solution (white color) and UV-Visible spectroscopy (maximum peak, at 320 nm). On a small scale, the Taguchi method was applied to improve the culture medium for culturing the strain E56. As a result, its cell-dry weight was 3.85 times that of the control condition. And then the biosynthesis of ZnO NPs (7.59 g/L) was increased by 1.6 times. Furthermore, by using the Plackett-Burman design to improve the utilized biogenesis pathway, the biosynthesis of ZnO NPs (18.76 g/L) was increased by 4.3 times. To find the best growth production line, we used batch and fed batch fermentation modes to gradually scale up biomass output. All kinetics of studied cell growth were evaluated during fed-batch fermentation as follows: biomass yield was 271.45 g/L, yield coefficient was 94.25 g/g, and ZnO NPs yield was 345.32 g/L. In vitro, the effects of various dosages of the controllable biosynthetic ZnO NPs as antimicrobial and anticancer agents were also investigated. The treatments with controllable biosynthetic ZnO NPs had a significant impact on all the examined multidrug-resistant human pathogens as well as cancer cells.

Dennis Mwanza Nzilu, Edwin Shigwenya Madivoli, David Sujee Makhanu et al.

Environmental Nanotechnology Monitoring & Management • 2023

Water shortage and scarcity are issues of global concern. Water pollution caused by organic micropollutants further aggravates the problem, by rendering an already scarce resource unfit for human consumption. The existing conventional wastewater treatment methods and infrastructure were not designed to eliminate micropollutants. Therefore, their inefficiencies call for modern methods for removing emerging micropollutant residues such as Active Pharmaceutical Ingredients (APIs), Endocrine Disrupting Compounds (EDCs), personal care products and pesticides. The use of nanomaterials, for the abatement of micropollutants in water is gaining traction in recent years, due to the abundance of sustainable, cost-effective raw materials, especially plant extracts. Synthesis of nanoparticles and their application in removal of micropollutants in wastewater streams is addressed through this review.

Zahra Sheykhifar, Seyed Majid Mohseni

Scientific Reports • 2022

Memristors-competitive microelectronic elements which bring together the electronic sensing and memory effects-potentially are able to respond against physical and chemical effects that influence their sensing capability and memory behavior. However, this young topic is still under debate and needs further attention to be highly responding to or remaining intact against physical effects, e.g., light illumination. To contribute to this scenario, using a composite of two-dimensional graphene or MoS 2 doped with meso-structures of metal/metal-oxides of Ag, Cu and Fe family, we presented scalable and printable memristors. The memristive behavior shows strong dependency upon light illumination with a high record of 10 5 ON/OFF ratio observed so far in 2-terminal systems based on two-dimensional materials or metal oxide structures. Moreover, we found that the memristors can remain stable without illumination, providing a novel approach to use these composites for developing neuromorphic computing circuits. The sensing and memristive mechanisms are explained based on the electronic properties of the materials. Our introduced materials used in the memristor devices can open new routes to achieve high sensing capability and improve memristance of the future microelectronic elements.

Dingling Wang, Zhaokun Ma, Yangen Xie et al.

RSC Advances • 2018

Rod-like CNTs were formed on Fe–N doped graphene during a simple carbonization process, and the mechanism of the growth and disappearance of CNTs were also investigated.

Halima Alnaqbi, Oussama M. El‐Kadri, Mohammad Ali Abdelkareem et al.

Energies • 2022

Supercapacitors (SCs) are recognized by high power densities and significantly higher cyclic stability compared to batteries. However, the energy density in SCs should be improved for better applications and commercialization. This could be achieved by developing materials characterized by such porous structures as metal-organic frameworks (MOFs) and metal chalcogenides in the electrodes’ materials. Herein, the recent advances in MOF derived from metal sulfides and selenides as electrode materials for SCs are reviewed and discussed. Strategies such as adopting core-shell structures, carbon-coating, and doping, which are used to promote the electrochemical performances of these MOF-based materials, are presented. Additionally, the progress in developing S-doped MOF-derived catalysts for the oxidation-reduction reaction (ORR) in the cathode of fuel cells is also reviewed. In addition, the challenges and future research trends are summarized in this minireview.

Dena Z. Khater, R.S. Amin, Mohamed Mahmoud et al.

RSC Advances • 2022

Oxygen reduction reaction (ORR) remains a pivotal factor in assessing the overall efficiency of energy conversion and storage technologies. A promising family of ORR electrocatalysts is mixed transition-metal oxides (MTMOs), which have recently gained a growing research interest. In this study, we developed MTMOs with different compositions (designated as A x B 3- x O 4 ; A = Cu, B = Co or Mn) anchored on two different carbon supports (activated carbon Vulcan XC-72 (AC) and graphene (G)) for catalyzing ORR in neutral media. Four different MTMO electrocatalysts ( i.e. , MnO 2 -CuO/AC, CoO-CuO/AC, CoO-CuO/G, and MnO 2 -CuO/G) were synthesized by a simple and scalable co-precipitation method. We documented the morphology and electrocatalytic properties of MTMO electrocatalysts using transmission and scanning electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectrometer (XPS), energy dispersive X-ray (EDX), and electrochemical techniques. Generally, MTMOs exhibited remarkably high ORR electrocatalytic activity with MTMOs anchored on an activated carbon support outperforming their respective MTMOs anchored on a graphene support, highlighting the importance of the catalyst support in determining the overall ORR activity of electrocatalysts. MnO 2 -CuO/AC has the highest diffusion limiting current density ( j ) value of 4.2 mA cm -2 at -600 mV ( vs. SHE), which is ∼1.1-1.7-fold higher than other tested electrocatalysts ( i.e. , 3.9, 3.5, and 2.7 mA cm -2 for CoO-CuO/AC, CoO-CuO/G, and MnO 2 -CuO/G, respectively), and slightly lower than Pt/C (5.1 mA cm -2 ) at the same potential value. Moreover, all electrocatalysts exhibited good linearity and parallelism of the Koutechy-Levich (K-L) plots, suggesting that ORR followed first-order reaction kinetics with the number of electrons involved being close to four. Benefiting from their remarkable ORR electrochemical activities and low cost, our results reveal that non-precious MTMOs are efficient enough to replace expensive Pt for broad applications in energy conversion and electrocatalysis in neutral media, such as microbial fuel cells.

Sheng Xu, Rui Zhang, Junpeng Cui et al.

Micromachines • 2021

In this paper, surface acoustic wave (SAW) sensors containing porous graphene/PVDF (polyvinylidene fluoride) molecularly imprinted sensitive membrane for DMMP gas detection were investigated. A 433 MHz ST-cut quartz SAW resonator was used to convert gas concentration changes into frequency shifts by the sensors. The porous graphene/PVDF film was fabricated on the sensor's surface by using the tape-casting method. DMMP molecules were adsorbed on the porous structure sensing film prepared by the 2-step method to achieve the specific recognition effect. The sensitivity of the sensor could reach -1.407 kHz·ppm -1 . The response time and recovery time of the SAW sensor with porous graphene/PVDF sensing membrane were about 4.5 s and 5.8 s at the concentration of 10 ppm, respectively. The sensor has good anti-interference ability to most gases in the air.

Sadia Khan, Tayyaba Nооr, Naseem Iqbal et al.

RSC Advances • 2023

Designing of non-noble, cost-effective, sustainable catalysts for water splitting is essential for hydrogen production. In this research work, ZIF-67, g-C 3 N 4 , and their composite (1, 3, 5, 6, 8 wt% g-C 3 N 4 @ZIF-67) are synthesized, and various techniques, XRD, FTIR, SEM, EDX and BET are used to examine their morphological properties for electrochemical water-splitting. The linkage of ZIF-67 with g-C 3 N 4 synergistically improves the electrochemical kinetics. An appropriate integration of g-C 3 N 4 in ZIF-67 MOF improves the charge transfer between the electrode and electrolyte and makes it a suitable option for electrochemical applications. In alkaline media, the composite of ZIF-67 MOF with g-C 3 N 4 over a Ni-foam exhibits a superior catalyst activity for water splitting application. Significantly, the 3 wt% g-C 3 N 4 @ZIF67 composite material reveals remarkable results with low overpotential values of -176 mV@10 mA cm -2 , 152 mV@10 mA cm -2 for HER and OER. The catalyst remained stable for 24 h without distortion. The 3 wt% composite also shows a commendable performance for overall water-splitting with a voltage yield of 1.34 v@10 mA cm -2 . The low contact angle (54.4°) proves the electrocatalyst's hydrophilic nature. The results of electrochemical water splitting illustrated that 3 wt% g-C 3 N 4 @ZIF-67 is an electrically conductive, stable, and hydrophilic-nature catalyst and is suggested to be a promising candidate for electrochemical water-splitting application.

Abhaysinh S. Khune, Vikky Padghan, Rameshwar P. Bongane et al.

Journal of Electronic Materials • 2023

Abstract The emergence of toxic pollutants due to heavy human intervention in the ecosystem causes serious environmental problems. Therefore, sensors based on material having a strong affinity towards specific environmental gaseous pollutants are urgently needed. The present study deals with chemiresistive gas sensors for the detection of sulfur dioxide (SO 2 ) based on a composite of reduced graphene oxide (rGO) and 5,10,15,20-tetrakis(4-aminophenyl) porphyrin (TAPP). The improved Hummers method was used to synthesize graphene oxide (GO); it was further thermally reduced to rGO. The pattern of the copper electrode was coated on glass slides with a shadow mask using thermal evaporation. Then, GO was drop-cast between the two copper electrodes, thermally reduced to obtain rGO, and then modified by TAPP. The spectroscopic, structural, morphological, electrical, and optical studies were carried out using Fourier transform infrared spectroscopy, x-ray diffraction, Raman spectroscopy, atomic force microscopy, field emission scanning electron microscopy, current–voltage (I–V) and UV–visible spectroscopy, respectively. The developed sensor shows high selectivity towards SO 2 gas analytes among exposed gaseous analytes. It exhibited reproducible response from 50 ppm to 200 ppm with enhanced repeatability at 50 ppm. The rGO/TAPP sensor exhibited a significant response (57 s) and recovery time (61 s), with a 5 ppm limit of detection. Graphical Abstract

Sandeep Kaushal, Gurmeet Kaur, Jasmeen Kaur et al.

Materials Advances • 2021

Metal organic frameworks (MOFs) have captured immense attention in the last decade, owing to their better adsorption properties as compared to those of organic as well as inorganic materials, like enormous surface area, highly porous nature, tunable pore size, and high stability.