Discover insights from thousands of peer-reviewed papers on microbial electrochemical systems
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.
Hanan Abdali, Bentolhoda Heli, Abdellah Ajji
Sensors · 2019
A nanocomposite of cross-linked bacterial cellulose-amino graphene/polyaniline (CLBC-AmG/PANI) was synthesized by covalent interaction of amino-functionalized graphene (AmG) AmG and bacterial cellulose (BC) via one step esterification, and then the aniline monomer was grown on the surface of CLBC-AmG through in situ chemical polymerization. The morphological structure and properties of the samples were characterized by using scanning electron microscopy (SEM), and thermal gravimetric analyzer (TGA). The CLBC-AmG/PANI showed good electrical-resistance response toward carbon dioxide (CO 2 ) at room temperature, compared to the BC/PANI nanopaper composites. The CLBC-AmG/PANI sensor possesses high sensitivity and fast response characteristics over CO 2 concentrations ranging from 50 to 2000 ppm. This process presents an extremely suitable candidate for developing novel nanomaterials sensors owing to easy fabrication and efficient sensing performance.
Andy Shar, Angela Shar, Daeha Joung
Frontiers in Bioengineering and Biotechnology · 2023
Carbon nanotube (CNT) nanocomposite scaffolds have emerged as highly promising frameworks for tissue engineering research. By leveraging their intrinsic electrical conductivity and valuable mechanical properties, CNTs are commonly dispersed into polymers to create robust, electrically conductive scaffolds that facilitate tissue regeneration and remodeling. This article explores the latest progress and challenges related to CNT dispersion, functionalization, and scaffold printing techniques, including electrospinning and 3D printing. Notably, these CNT scaffolds have demonstrated remarkable positive effects across various cell culture systems, stimulating neuronal growth, promoting cardiomyocyte maturation, and facilitating osteocyte differentiation. These encouraging results have sparked significant interest within the regenerative medicine field, including neural, cardiac, muscle, and bone regenerations. However, addressing the concern of CNT cytotoxicity in these scaffolds remains critical. Consequently, substantial efforts are focused on exploring strategies to minimize cytotoxicity associated with CNT-based scaffolds. Moreover, researchers have also explored the intriguing possibility of utilizing the natural cytotoxic properties of CNTs to selectively target cancer cells, opening up promising avenues for cancer therapy. More research should be conducted on cutting-edge applications of CNT-based scaffolds through phototherapy and electrothermal ablation. Unlike drug delivery systems, these novel methodologies can combine 3D additive manufacturing with the innate physical properties of CNT in response to electromagnetic stimuli to efficiently target localized tumors. Taken together, the unique properties of CNT-based nanocomposite scaffolds position them as promising candidates for revolutionary breakthroughs in both regenerative medicine and cancer treatment. Continued research and innovation in this area hold significant promise for improving healthcare outcomes.
Amar Kamal Mohamedkhair, Q.A. Drmosh, Zain H. Yamani
Frontiers in Materials · 2019
In this work, sputtered tin oxide films, decorated with silver nanoparticles were fabricated as hydrogen sensors. The fabricated thin films were characterized for their structural, compositional, morphological properties using various characterization techniques including X-ray photoelectron spectroscopy, UV-Vis absorption, X-Ray diffraction, field emission scanning electron microscope, and atomic force microscopy. The morphological characterization confirmed the formation of nanoparticles decorated SnO2 thin films. X-ray photoelectron spectroscopy spectroscopic analysis established the presence of silver/silver oxide on SnO2 thin films. The gas sensing properties of the fabricated sensors were investigated at different concentrations of hydrogen gas, over an operating temperature range of room temperature to 500 °C. It was found that the prepared sensor can detect a low hydrogen concentration (50 ppm) at high operation temperature, while the higher concentration (starting from 600 ppm) can be detected even at room temperature. Furthermore, on the basis of the electronic interaction between the SnO2 and the Ag nanoparticles, we propose a reaction model to explain the qualitative findings of the study.
Jin-Ho Son, Hongseok Kim, Yoonseob Choi et al.
Microsystems & Nanoengineering · 2024
The energy devices for generation, conversion, and storage of electricity are widely used across diverse aspects of human life and various industry. Three-dimensional (3D) printing has emerged as a promising technology for the fabrication of energy devices due to its unique capability of manufacturing complex shapes across different length scales. 3D-printed energy devices can have intricate 3D structures for significant performance enhancement, which are otherwise impossible to achieve through conventional manufacturing methods. Furthermore, recent progress has witnessed that 3D-printed energy devices with micro-lattice structures surpass their bulk counterparts in terms of mechanical properties as well as electrical performances. While existing literature focuses mostly on specific aspects of individual printed energy devices, a brief overview collectively covering the wide landscape of energy applications is lacking. This review provides a concise summary of recent advancements of 3D-printed energy devices. We classify these devices into three functional categories; generation, conversion, and storage of energy, offering insight on the recent progress within each category. Furthermore, current challenges and future prospects associated with 3D-printed energy devices are discussed, emphasizing their potential to advance sustainable energy solutions.
Hongchuan Jiang, Yibing Yu, Luying Zhang et al.
Sensors · 2019
A highly sensitive and flexible hydrogen sensor based on organic nanofibers decorated by Pd nanoparticles (NPs) was designed and fabricated for low-concentration hydrogen detection. Pd NPs were deposited on organic nanofiber materials by DC magnetron sputtering. The temperature dependence of the sensitivity at 25 ppm H₂ was characterized and discussed, and the maximum response of the sensor increased linearly with increasing measurement temperature. Performances of the hydrogen sensor were investigated with hydrogen concentration ranging from 5 ppm to 50 ppm. This sensor exhibits high sensitivity, with the response up to 6.55% for H₂ as low as 5 ppm, and the output response of the hydrogen sensor increased linearly with the square root of hydrogen concentration. A cycling test between pure nitrogen and 25 ppm hydrogen concentration was performed, and the hydrogen sensor exhibited excellent consistency.
Sanna Siljander, Pasi Keinänen, Anna Räty et al.
International Journal of Molecular Sciences · 2018
We present a detailed study on the influence of sonication energy and surfactant type on the electrical conductivity of nanocellulose-carbon nanotube (NFC-CNT) nanocomposite films. The study was made using a minimum amount of processing steps, chemicals and materials, to optimize the conductivity properties of free-standing flexible nanocomposite films. In general, the NFC-CNT film preparation process is sensitive concerning the dispersing phase of CNTs into a solution with NFC. In our study, we used sonication to carry out the dispersing phase of processing in the presence of surfactant. In the final phase, the films were prepared from the dispersion using centrifugal cast molding. The solid films were analyzed regarding their electrical conductivity using a four-probe measuring technique. We also characterized how conductivity properties were enhanced when surfactant was removed from nanocomposite films; to our knowledge this has not been reported previously. The results of our study indicated that the optimization of the surfactant type clearly affected the formation of freestanding films. The effect of sonication energy was significant in terms of conductivity. Using a relatively low 16 wt. % concentration of multiwall carbon nanotubes we achieved the highest conductivity value of 8.4 S/cm for nanocellulose-CNT films ever published in the current literature. This was achieved by optimizing the surfactant type and sonication energy per dry mass. Additionally, to further increase the conductivity, we defined a preparation step to remove the used surfactant from the final nanocomposite structure.
Bárbara Socas‐Rodríguez, Antonio V. Herrera‐Herrera, María Asensio‐Ramos et al.
Processes · 2020
Nanotechnology has become a topic of interest due to the outstanding advantages that the use of nanomaterials offers in many fields. Among them, magnetic nanoparticles (m-NPs) have been one of the most widely applied in recent years. In addition to the unique features of nanomaterials in general, which exclusively appear at nanoscale, these present magnetic or paramagnetic properties that result of great interest in many applications. In particular, in the area of food analysis, the use of these nanomaterials has undergone a considerable increase since they can be easily separated from the matrix in sorbent-based extractions, providing a considerable simplification of the procedures. This allows reducing cost and giving fast responses, which is essential in the food trade to guarantee consumer safety. These materials can also be easily tunable, providing higher selectivity. Moreover, their particular electrical, thermal and optical characteristics allow enhancing sensor signals, increasing the sensitivity of the approaches based on this type of device. The aim of this review article is to summarise the most remarkable applications of m-NPs in food analysis in the last five years (2016–2020) showing a general view of the use of such materials in the field.
Xiyi Li, Chao Wang, Jianlong Yang et al.
Nature Communications · 2023
Methane activation by photocatalysis is one of the promising sustainable technologies for chemical synthesis. However, the current efficiency and stability of the process are moderate. Herein, a PdCu nanoalloy (~2.3 nm) was decorated on TiO 2 , which works for the efficient, stable, and selective photocatalytic oxidative coupling of methane at room temperature. A high methane conversion rate of 2480 μmol g -1 h -1 to C 2 with an apparent quantum efficiency of ~8.4% has been achieved. More importantly, the photocatalyst exhibits the turnover frequency and turnover number of 116 h -1 and 12,642 with respect to PdCu, representing a record among all the photocatalytic processes (λ > 300 nm) operated at room temperature, together with a long stability of over 112 hours. The nanoalloy works as a hole acceptor, in which Pd softens and weakens C-H bond in methane and Cu decreases the adsorption energy of C 2 products, leading to the high efficiency and long-time stability.