Ling Zhang, Xuqiang Ji, Xiang Ren et al.

Advanced Materials • 2018

The discovery of stable and noble‐metal‐free catalysts toward efficient electrochemical reduction of nitrogen (N2) to ammonia (NH3) is highly desired and significantly critical for the earth nitrogen cycle. Here, based on the theoretical predictions, MoS2 is first utilized to catalyze the N2 reduction reaction (NRR) under room temperature and atmospheric pressure. Electrochemical tests reveal that such catalyst achieves a high Faradaic efficiency (1.17%) and NH3 yield (8.08 × 10−11 mol s−1 cm−1) at −0.5 V versus reversible hydrogen electrode in 0.1 m Na2SO4. Even in acidic conditions, where strong hydrogen evolution reaction occurs, MoS2 is still active for the NRR. This work represents an important addition to the growing family of transition‐metal‐based catalysts with advanced performance in NRR.

J. Nutting, M. Rafiee, S. Stahl

Chemical Reviews • 2018

N-Oxyl compounds represent a diverse group of reagents that find widespread use as catalysts for the selective oxidation of organic molecules in both laboratory and industrial applications. While turnover of N-oxyl catalysts in oxidation reactions may be accomplished with a variety of stoichiometric oxidants, N-oxyl reagents have also been extensively used as catalysts under electrochemical conditions in the absence of chemical oxidants. Several classes of N-oxyl compounds undergo facile redox reactions at electrode surfaces, enabling them to mediate a wide range of electrosynthetic reactions. Electrochemical studies also provide insights into the structural properties and mechanisms of chemical and electrochemical catalysis by N-oxyl compounds. This review provides a comprehensive survey of the electrochemical properties and electrocatalytic applications of aminoxyls, imidoxyls, and related reagents, of which the two prototypical and widely used examples are 2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO) and phthalimide N-oxyl (PINO).

Weiran Zheng, Mengjie Liu, L. Lee

ACS Catalysis • 2020

Despite recent attempts using metal–organic frameworks (MOFs) directly as electrocatalysts, the electrochemical stability of MOFs and the role of in situ-formed species during electrochemistry are ...

Leigang Li, Pengtang Wang, Qi Shao et al.

Chemical Society Reviews • 2020

Metallic nanostructures with low dimensionality (one-dimension and two-dimension) possess unique structural characteristics and distinctive electronic and physicochemical properties including high aspect ratio, high specific surface area, high density of surface unsaturated atoms and high electron mobility. These distinctive features have rendered them remarkable advantages over their bulk counterparts for surface-related applications, for example, electrochemical water splitting. In this review article, we highlight the recent research progress in low-dimensional metallic nanostructures for electrochemical water splitting including hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Fundamental understanding of the electrochemistry of water splitting including HER and OER is firstly provided from the aspects of catalytic mechanisms, activity descriptors and property evaluation metrics. Generally, it is challenging to obtain low-dimensional metallic nanostructures with desirable characteristics for HER and OER. We hereby introduce several typical methods for synthesizing one-dimensional and two-dimensional metallic nanostructures including organic ligand-assisted synthesis, hydrothermal/solvothermal synthesis, carbon monoxide confined growth, topotactic reduction, and templated growth. We then put emphasis on the strategies adopted for the design and fabrication of high-performance low-dimensional metallic nanostructures for electrochemical water splitting such as alloying, structure design, surface engineering, interface engineering and strain engineering. The underlying structure-property correlation for each strategy is elucidated aiming to facilitate the design of more advanced electrocatalysts for water splitting. The challenges and perspectives for the development of electrochemical water splitting and low-dimensional metallic nanostructures are also proposed.

R. Marcus

Annual Review of Physical Chemistry • 1964

One of the active areas in reaction kinetics during the post-war years has been that of electron-transfer reactions. These reactions constitute one type of oxidation-reduction process and include both chemical and electrochemical systems. Many rate constants have now been measured (1-8) and they have stimulated a variety of theoretical studies (9-37). The field has been characterized by a strong interplay of theory and experiment, which now includes the testing of theoretically predicted quantitative correlations (34). Because of a certain unique feature of the purely electron-transfer reactions--the absence of bond rupture in the reaction step--these correlations are unusual. They do not have the arbitrary parameters that occur in theoretical studies of most other reactions in chemical kinetics. This review will be limited to purely electron transfer reactions.

Ming Yan, Yuki Kawamata, P. Baran

Chemical Reviews • 2017

Electrochemistry represents one of the most intimate ways of interacting with molecules. This review discusses advances in synthetic organic electrochemistry since 2000. Enabling methods and synthetic applications are analyzed alongside innate advantages as well as future challenges of electroorganic chemistry.

Stephanie Nitopi, Erlend Bertheussen, S. Scott et al.

Chemical Reviews • 2019

To date, copper is the only heterogeneous catalyst that has shown a propensity to produce valuable hydrocarbons and alcohols, such as ethylene and ethanol, from electrochemical CO2 reduction (CO2R). There are variety of factors that impact CO2R activity and selectivity, including the catalyst surface structure, morphology, composition, the choice of electrolyte ions and pH, and the electrochemical cell design. Many of these factors are often intertwined, which can complicate catalyst discovery and design efforts. Here we take a broad and historical view of these different aspects and their complex interplay in CO2R catalysis on Cu, with the purpose of providing new insights, critical evaluations, and guidance to the field with regard to research directions and best practices. First, we describe the various experimental probes and complementary theoretical methods that have been used to discern the mechanisms by which products are formed, and next we present our current understanding of the complex reaction networks for CO2R on Cu. We then analyze two key methods that have been used in attempts to alter the activity and selectivity of Cu: nanostructuring and the formation of bimetallic electrodes. Finally, we offer some perspectives on the future outlook for electrochemical CO2R.

A. Bard, L. Faulkner

Journal of Chemical Education • 1980

A review of a book intended to serve as both a course text at the senior-graduate level and as a reference book for those who wish to evaluate electrochemical methods as research tools.

Tatiana Magdesieva

Electrochemical Science Advances • 2022

Abstract Possible approaches to molecular design of stable diarylnitroxyl radicals capable to form sufficiently stable cations and anions under one‐electron oxidation and reduction are discussed. Both covalent and noncovalent stabilizing “tools” are considered. The main focus is made on the dynamic stabilization of oppositely charged redox states of a molecule through conformational changes. The efficiency of the approaches was confirmed on a wide range of novel diarylnitroxides designed accordingly to the suggested guidelines. Spectral and quantum‐chemical data support fast conformational changes accompanying electron transfer steps and facilitating stabilization of the cationic and anionic species. Voltammetric study of new compounds revealed the formation of reversible redox couples in both anodic and cathodic areas for the majority of nitroxides making them suitable for practical application.

Fundamentals of Electrochemical Corrosion • 2000

Abstract This chapter provides a thorough introduction to the electrochemical thermodynamics that govern electrode reactions associated with corrosion. It begins with a review of the thermodynamic criteria for the stability of chemical reactions based on Gibbs free energy and explains how energies of formation are determined using the oxidation of iron as an example. It then considers how iron reacts with hydrochloric acid, explaining how it can be expressed as two half reactions modeled as electrodes in an electrochemical cell. It goes on to describe the chemical reactions occurring at each electrode, accounting for different variables, mechanisms, and electrochemical effects. The chapter concludes with an in-depth review of Pourbaix diagrams, explaining what they reveal about the stability of metal-water systems and the formation of corrosion products.

, D. G. Kondrat'ev, V. I. Matrenin et al.

Electrochemical Energetics • 2009

The paper deals with some questions concerning carbonization and decarbonization of alkaline electrolyte in matrix fuel cell (FC). It is shown that there is an equilibrium ultimate level of carbonization that depends on CO2 content in gases delivered into FC and FC electric loading. Electrolyte decarbonization takes place at the increase of FC load current with CO2 emission at hydrogen electrode end. The possible mechanisms of electrolyte carbonization and decarbonization are suggested.

, K. G. Bol'shakov, D. G. Kondrat'ev et al.

Electrochemical Energetics • 2009

The method for air purification from carbon dioxide gas in operating electrochemical cell at oxygen pump mode is considered. The work suggests a mechanism of CO2 removal. The effect of a number of parameters to CO2 removal is discussed. A scheme of module application for air purification from CO2 completed with Alkaline Fuel Cell Stack (AFCS) is proposed. Provided is a method for alkaline electrolyte decarbonization.

Brian J. Eddie, Zheng Wang, W. Judson Hervey et al.

bioRxiv (Cold Spring Harbor Laboratory) • 2016

Abstract Biocathodes provide a stable electron source to drive reduction reactions in electrotrophic microbial electrochemical systems. Electroautotrophic biocathode communities may be more robust than monocultures in environmentally relevant settings, but some members are not easily cultivated outside of the electrode environment. We previously used metagenomics and metaproteomics to propose a pathway for coupling extracellular electron transfer (EET) to carbon fixation in “ Candidatus Tenderia electrophaga”, an uncultivated but dominant member of the Biocathode-MCL electroautotrophic community. Here we validate and refine this proposed pathway using differential metatranscriptomics of replicate MCL reactors poised at the growth potential 310 mV and the suboptimal 470 mV (vs. standard hydrogen electrode). At both potentials, transcripts from “ Ca . Tenderia electrophaga” were more abundant than from any other organism and its relative activity was positively correlated with current. Several genes encoding key components of the proposed “ Ca . Tenderia electrophaga” EET pathway were more highly expressed at 470 mV, consistent with a need for cells to acquire more electrons to obtain the same amount of energy as at 310 mV. These included cyc2 , encoding a homolog of a protein known to be involved in iron oxidation, confirmed to be differentially expressed by droplet digital PCR of independent biological replicates. Average expression of all CO 2 fixation related genes is 1.23-fold higher at 310 mV, indicating that reduced energy availability at 470 mV decreased CO 2 fixation. Our results substantiate the claim that “ Ca . Tenderia electrophaga” is the key MCL electroautotroph, which will help guide further development of this community for microbial electrosynthesis. IMPORTANCE Bacteria that directly use electrodes as metabolic electron donors (biocathodes) have been proposed for applications ranging from microbial electrosynthesis to advanced bioelectronics for cellular communication with machines. However, just as we understand very little about oxidation of analogous natural insoluble electron donors, such as iron oxide, the organisms and extracellular electron transfer (EET) pathways underlying the electrode-cell direct electron transfer processes are almost completely unknown. Biocathodes are a stable biofilm cultivation platform to interrogate both the rate and mechanism of EET using electrochemistry and study the electroautotrophic organisms that catalyze these reactions. Here we provide new evidence supporting the hypothesis that the uncultured bacterium “ Candidatus Tenderia electrophaga” directly couples extracellular electron transfer to CO 2 fixation. Our results provide insight into developing biocathode technology, such as microbial electrosynthesis, as well as advancing our understanding of chemolithoautotrophy.

Noya Loew, Isao Shitanda, Himeka Goto et al.

Research Square • 2022

Abstract In this study, the performance of a paper-based, screen-printed biofuel cell with mesoporous MgO-templated carbon (MgOC) electrodes was improved in two steps. First, a small amount of carboxymethyl cellulose (CMC) was added to the MgOC ink. Next, the cathode was modified with bilirubin prior to immobilizing the bilirubin oxidase (BOD). The CMC increased the accessibility of the mesopores of the MgOC, and subsequently, the performance of both the bioanode and biocathode. CMC also likely increased the stability of the electrodes. The pre-modification with bilirubin improved the orientation of the BOD, which facilitated direct electron transfer. With these two steps, an open circuit potential of 0.65 V, a maximal current density of 1.94 mA cm -2 , and a maximal power density of 465 μW cm -2 was achieved with lactate oxidase as bioanode enzyme and lactate as fuel. This is one of the highest reported performances for a biofuel cell.

Mary Arugula, Erica Pinchon, Kapil Pant et al.

ECS Meeting Abstracts • 2018

Recent studies have focused on tailoring the catalytic currents of multicopper oxidase (MCO) enzymes-based biocathodes to enhance oxygen reduction. Biocathodes modified with natural substrates specific for MCO enzymes demonstrated drastic improvement for oxygen reduction. Performance of 1- pyrenebutanoic acid, succinimidyl ester (PBSE) and 2,5- dimethyl-1-phenyl-1H-pyrrole-3-carbaldehyde (Di-Carb) oriented bilirubin oxidase (BOx) modified gas diffusion biocathode has been drastically improved by incorporating, a porphyrin precursor as electron transfer moiety. Porphyrin precursor modified electrodes demonstrated direct electron transfer reaction of BOx exhibiting larger O 2 reduction current density in phosphate buffer solution (pH 7.0) without the need of a mediator. A remarkable improvement in the catalytic currents with 2.5 fold increase was achieved compared to non-modified oriented BOx electrodes. Moreover, a mediator-less and compartment-less Glucose/O 2 biofuel cell based on direct electron transfer (DET) type bioelectrocatalysis via the BOx-cathode and the glucose dehydrogenase (GDH)-anode demonstrated peak power densities of 1mW/cm 2 at pH 7.0 with 100mM glucose/10mM NAD fuel. The maximum current density of 1.6mA/cm 2 and the maximum power density of 0.4mW/cm 2 were achieved at 300mV with non modified BOx cathode, while 3.5mA/cm 2 and 1.1mW/cm 2 of current and power density was achieved with porphyrin precursor modified cathode. The performance improved 2.4 times which attributes to the porphyrin precursor acting as a natural substrate and activator for BOx activity enhancement.

Sadagopan Krishnan

ECS Meeting Abstracts • 2020

Understanding the characteristics of nanomaterials in the context of electrode designs for bio-electrocatalysis is an emerging research direction. Applications for fuel cells, batteries, and biosensors are directly benefited. The objective of this study is to understand the influence of unfunctionalized multiwalled carbon nanotubes (MWNT) in comparison to carboxylated nanotubes (MWNT–COOH) for pi-pi stacking with 1-pyrenebutyric acid (Py) and covalent immobilization of bilirubin oxidase (BOD) enzyme toward the resulting oxygen reduction currents. We designed pyrolytic graphite-edge electrodes modified with MWNT/Py, MWNT–COOH/Py, or only MWNT–COOH for carbodiimide activation and BOD immobilization. The relative increase in surface –COOH groups as we move from MWNT to MWNT/Py to MWNT–COOH/Py modification is voltammetrically estimated. Although the MWNT–COOH/Py displayed the highest relative amount of surface −COOH groups, the oxygen reduction current was the largest for the BOD-immobilized MWNT/Py electrode than others. Results indicate that unfunctionalized MWNT is the optimal choice for pi-pi stacking with pyrene linkers and covalent BOD immobilization as biocathode for direct electrocatalysis with high current densities. Favorable hydrophobic MWNT surface to interact more closely with the electron-receiving T1 Cu site of BOD, as opposed to the relatively polar and more defective MWNT–COOH material due to functionalization, is suggested to be one of the underlying factors for the observed electrocatalytic trend.

Min Su, Liling Wei, Zhaozheng Qiu et al.

RSC Advances • 2015

Graphene can dramatically improve the performance of biocatalyst for hydrogen production by modifying biocathode.

Mahshid Loloei, Abbas Rezaee, Ghazaleh Ghods

Research Square • 2021

Abstract The present study evaluated effect of conductive microbial cellulose (MC) biocathode as a carbohyrate biopolymer in hexavalent chromium bio-electroreduction using immobilized sulfate reducing bacteria (SRB). The morphology studies using SEM shows that the biofilm of SRB was formed a good density on the conductive microbial cellulose biocathode. The Brunauer, Emmett and Teller (BET) analysis revealed that the particle-size distribution in the conductive biocathode was 0.9 nm. The kinetic studies shows that the Cr (VI) removal process fallow of pseudo-first-order kinetics with a constant rate was 0.6 h − 1 . The energy consumption of the bio-electroreduction system was 2.7×10 − 2 kWh/m 3 . The EDXA spectrum of sediments showed the presence of chromium peak, indicating that Cr (VI) was reduced on the bio-resuction system. The obtained results indicate that proposed bio-electroreduction system using immobilized sulfate reducing bacteria on the conductive microbial cellulose biocathode could be an efficient method for chromium bio-reduction from wastewaters.

Okan Avcı, Merve Sezer Kürkçü, Bekir Çöl et al.

ChemistrySelect • 2023

Abstract In this work, a bioanode which was based on carbon felt electrode (CFE) that contained highly boron tolerant bacterium Pseudomonas sp . isolated from a boron mine (Pseudomonas isolate BC4B) and iron‐metal organic framework (Fe‐MOF) was developed. To the best of our knowledge, this is the first study in which a highly boron tolerant bacterium, Pseudomonas isolate BC4B was investigated as a bioanode material. It was observed that Fe‐MOF increased the signal significantly by behaving as a catalyst. During the study, the optimization of Fe‐MOF amount, bacteria amount and substrate concentration were done. Also, the effect of different substrate amounts on the bioanode electrochemical signal was investigated. Consequently, the highest current density value was obtained with 5 mM substrate amount. Meanwhile, in order to investigate the reproducibility of developed bioanode, relative standard deviation value was calculated and found as 1.39 % (n : 3) for 4 mM concentration of H 3 BO 3 .

Kenichi Murata, Shuji Fujita, Shun Yamanoi et al.

ECS Meeting Abstracts • 2012

Abstract not Available.

Muhammad Nadeem Zafar, Iqra Aslam, Shahzad Murtaza et al.

ECS Meeting Abstracts • 2016

To improve communications between enzymes and electrodes, many different methods were developed including the use of diffusional electron mediators, the “wiring” of enzymes through immobilization in redox polymers, the functionalization of enzymes with electron relays, and the use of nanomaterials. Recently a new promising strategy was reported, in which the glycoprotein glucose oxidase (GOx) was directly electrically contacted with the electrodes after removal of the glycosylating layer. Although a lot of advances in the electrical communication between enzymes and electrodes has made it possible to fabricate new biosensors and biofuel cells, the technologies still face challenging issues, such as development of long-term stable miniaturized implantable amperometric biosensors and biofuel cells. Our approach to the development of a glucose biofuel cell anode is based on the combination of different redox enzymes with complementary oxidation positions thus forming a reaction cascade to oxidize the substrate at more than one position. Improvements in current density and coulombic efficiency of a glucose oxidizing electrode were realized by a combination of pyranose dehydrogenase from Agaricus meleagris ( Am PDH) with either glucose dehydrogenase from Glomerella cingulata ( Gc GDH) or cellobiose dehydrogenase from Myriococcum thermophilum ( Mt CDH). The mixed enzyme electrode oxidizes glucose in several combinations at the C-1, C-2 and C-3 positions of the pyranose ring. This concerted action of enzymes increases (i) the coulombic efficiency by extracting more than 2 e - per substrate molecule and (ii) the current density of the electrode when the mass-transfer of substrates becomes rate limiting. The electrodes were investigated with flow injection analysis (FIA) using different substrates under physiological conditions (pH 7.4). These investigations showed that the product of one enzyme can be used as substrate for the other enzyme and maximally 6 e - can be gained from the oxidation of one glucose molecule using mixed enzyme electrodes like Am PDHb/ Gc GDH/Os-polymer 2 or the Am PDHa/ Mt CDH/Os-polymer 1. We propose a bioanode for use in biofuel cells with an increased current density and coulombic efficiency obtained by a cascade reaction catalyzed by redox enzymes with a different site-specificity for glucose.

Kenji Kano

ECS Meeting Abstracts • 2014

In order to realize the promising hydrogen energy conversion system, a superior catalyst to oxidize hydrogen is needed. Nowadays, the power devices such as an H 2 /O 2 fuel cell rely on platinum as a catalyst, which is a rare metal and thus too expensive. Many researchers have explored alternative catalysts. From the aspect of bioelectrochemistry, hydrogenase that catalyzes the redox reaction between hydrogen and proton have received a lot of attention, and the bioelectrocatalytic properties has extensively been characterized all over the world. The discovery of O 2 - and CO-tolerant [NiFe]-hydrogenase is one of the breakthroughs essential for the construction of the aforementioned biofuel cell, and the unique properties have been investigated from several viewpoints. One critical problem in utilization of [NiFe]-hydrogenase is reversible inactivation caused by the anaerobic oxidation at high electrode potential or high solution potential. Several spectroscopic studies have revealed that the catalytic cycle proceeds in three states: Ni-SI (active silent form), Ni-R (H 2 -reduced form), Ni-C (one-electron oxidized form of Ni-R), and that the inactivation generates a Ni(III) state form known as Ni-B by one-electron oxidation of Ni-SI, in which a hydroxide ligand is coordinated to the Ni atom in a bridging position with respect to the Fe(II). A membrane-bound [NiFe]-hydrogenase (MBH) from Hydrogenoviblio marinus allows a direct electron transfer (DET)-type bioelectrocatalysis for the H 2 oxidation and is an O 2 -tolerant promising enzyme for the construction of enzymatic H 2 /O 2 biofuel cells. From the practical viewpoint of the electricity production, the H 2 depletion near the electrode surface and the oxidative and reversible inactivation (as a competitive inhibition) of [NiFe]-hydrogenases limit the H 2 oxidation, and consequently causes the power decline. In this research, the Michaelis constant has been evaluated as 0.57 mM under steady-state conditions for the DET-type H 2 oxidation by MBH chemically immobilized on Ketjien black mesoporous carbon electrode. In order to spontaneously supply H 2 from the gas phase and to avoid the inactivation, an MBH-adsorbed gas-diffusion-type electrode has been constructed. The maximum current density of H 2 oxidation has reached about 6 mA cm - 2 at 0 V (vs. Ag|AgCl|sat. KCl electrode) under quiescent (passive) and H 2 atmospheric conditions.

Aishwarya Mahadevan, Sandun Fernando

ECS Meeting Abstracts • 2016

Biomolecules are inherently less conductive. Therefore, bio-electronic devices that depend on conventional biomolecules to tether enzymes onto electrode supports and to shuttle electrons between the enzyme and the electrode suffer from charge dissipation. This results in bioanondes with decreased current-voltage responses as a result of ohmic losses. Thus, lack of an effective molecular wiring system that can allow unimpeded charge transport is a significant problem that hinders our ability to utilize the full potential of enzymatic self-powering bioelectronic devices. Reducing the internal resistance is the simplest way of increasing the current-voltage response associated with bioanodes and has yet been an unmet challenge. In living cells, iron-sulfur complexes ([Fe-S]) are known to aid in circumventing these issues in the mitochondrial electron transport chains. We describe a technique to attach iron-sulfur moieties to gold surface in non-aqueous media initially and then continue coenzyme and apoenzyme attachment in aqueous media while keeping the efficacy of FeS and the enzyme system intact. As a working model, a glycerol-sensitive gold bioanode is described based on direct attachment of the glycerol-dehydrogenase (GlDH)-NAD + apoenzyme-coenzyme complex onto the supporting gold surface using iron (II) sulfide (FeS) mediation. A conventional pyrroloquinoline quinone (PQQ)-based electrode was used as the control. The performances of the two electrode systems were compared using amperometric and potentiometric studies. Successful tethering of the molecular wiring schemes was verified using cyclic voltammetry and spectroscopy. Amperometric and potentiometric analyses with glycerol dehydrogenase-based model electrodes confirmed the ability of this single-molecule to remarkably amplify, about ten-fold increase in current and up to 24% increase in voltage outputs, as compared to electrodes fabricated with the conventional PQQ-based composite molecular wiring system. FeS achieves the dual purpose of anchoring the enzyme to the gold electrode while also mediating electron shuttling between coenzyme and the electrode surface. This dual functionality allows usage of a single-molecular wire to foster electrical communication between the enzyme and the electrode instead of the conventional multi-molecular wiring system and in turn reducing the internal resistance of the electrode. The resulting increase in current/voltage response opens up a wide range of possibilities for developing efficient bio-electrodes for bioelectronics applications. The importance of this work is the ability to reduce the internal resistance (and thus the overpotential) of circuits that use redox enzymes - allowing complete utilization of the “available power” and “signal capacity” in enzyme-based bioelectronic systems.

Aya Kontani, Miyuki Masuda, Nobuhumi Nakamura et al.

ECS Meeting Abstracts • 2012

Abstract not Available.

Shelley D. Minteer, Shuai Xu

ECS Meeting Abstracts • 2014

PQQ-dependent multi-heme containing aldehyde dehydrogenase (PQQ-AlDH) has been previously demonstrated to be capable of performing direct electron transfer (DET). However, theory predicts that the rate of direct bioelectrocatalysis for complex multi-subunit proteins such as PQQ-AlDH is closely related to the proximity and orientation of the enzymes toward the electrode surface, which determines the electron tunneling distances and the current density. In order to investigate the impact of enzyme orientation on the catalysis rate, we immobilized PQQ-AlDH via a site specific immobilization technique to form a monolayer of biocatalysts with a uniform orientation on a gold electrode. Six recombinant PQQ-AlDHs were employed, where the enzymes had been labeled with six-histidine tags (His-tag) at the N- or C-terminus of each of the three subunits. These His-tags were utilized as linking sites to perform site specific isotropic immobilization of PQQ-AlDHs. Results show that the orientation of PQQ-AlDHs can affect direct biocatalysis rate greatly by varying the electron tunneling distances. The favorable orientation with a minimal heme c electron transfer distance showed a current density that is 6.6-fold higher than the electrode with the orientation closest to the active site of the enzyme, while the unfavorable attachment to a non-electroactive subunit showed no bioelectrocatalytic current.

Aishwarya Mahadevan, Sandun Fernando

ECS Meeting Abstracts • 2017

Immobilization of NAD-dependent redox enzymes on electrode surfaces has been widely reported for the construction of enzymatic biosensors for detection of various biomolecules in different industries. Molecular wiring of such redox enzymes facilitate an efficient electron transfer by connecting redox center of the enzyme with the electrode surface. Iron-sulfur complexes are known for being the firstlink between protein and the mediating molecules in the mitochondrial electron transport chain to abstract electrons from NAD + . The application of iron-sulfur molecules as molecular wires to mediate electron transport between NAD-dependent glucose dehydrogenase (NAD-GDH) and gold electrode surface (i.e. a glucose bioanode) was studied. Methodology for fabrication and characterization of iron-sulfur based glucose biosensor at different construction stages were described. The biosensor performance characteritics of the novel Fe-S based glucose biosensor was investigated using amperometric analyses in the presence of glucose.

Rurika Toda, Ryoichi Tatara, Tatsuo Horiba et al.

ChemElectroChem • 2021

Abstract Invited for this month's cover picture is an invited contribution from the Shinichi Komaba group at the Tokyo University of Science. The cover picture shows a cascading reaction occurring at the multi‐enzyme‐modified bioanode, decomposing starch molecules to glucose, followed by glucose oxidation. Read the full text of the Article at 10.1002/celc.202100843 .

Xiaoyan He, Zheping Tan, Miaomiao Hou et al.

Research Square • 2024

Abstract Microbial fuel cells (MFCs) have garnered significant attention in power generation and wastewater treatment fields. Current MFCs have relatively low power density due to limited biofilm colonization and sluggish extracellular electron transfer (EET) processes. Here, a hybrid hydrogel (PPy-CMC-MXene) was prepared by doping MXene with an inexpensive and readily available biomass source carboxymethyl cellulose and polypyrrole. The MFC equipped with the PPy-CMC-MXene/CC anode exhibited a 2-, 30-, 59-, and 4.8-fold power density, specific capacitance, electron transfer efficiency, and coulombic efficiency, respectively, relative to the original carbon cloth (CC) anode. More notably, the MFC equipped with the PPy-CMC-MXene/CC anode had an excellent chemical oxygen demand (COD) removal efficiency of 89.2%. It was shown that the PPy-CMC-MXene/CC electrode offered good biocompatibility and was beneficial to the enrichment of Proteobacteria and Acinetobacter . The anode material has some application prospects in water treatment and the adsorption of electricity-producing bacteria.

Fuel Cells Bulletin • 2020

Doosan Mobility Innovation has used its hydrogen PEM fuel cell drone to distribute protective face masks to residents on several small islands around Jeju Island, off the southwestern tip of South Korea.

Fuel Cells Bulletin • 2018

Korea Midland Power Company (KOMIPO) has teamed up with Korea Expressway Corporation (KEC), KyungDong City Gas and SK E&C (Engineering & Construction) to implement a KRW100 billion (US$90 million) fuel cell power generation project in South Korea, expected to begin operation in 2020.

P. Leão

The Biochemist • 2022

A cancer patient treated with a molecule found in algae-eating sea hares native to the Indian Ocean. Jet fuel produced by algae in open urban ponds. A tonne-scale synthesis of pharmaceuticals using enzymes from a green biofilm growing in your backyard. The first example is a reality, but the others are not necessarily confined to a utopian future. All these scenarios can be linked to blue-green algae (cyanobacteria). These talented microbial biochemists generate a vast set of unique secondary (specialized) metabolites. Initially infamous for being potent toxins that have resulted in human deaths, some cyanobacterial secondary metabolites have proven useful and are currently used in the clinic. The enzymes that biosynthesize some of these compounds are likewise remarkable and could find future industrial use. Here, I discuss some aspects of past and current secondary metabolite discovery in cyanobacteria, the potential impact of these small molecules for human activities and how the study of their biosynthesis has unearthed exciting new enzymatic reactions.

, George Patani

INDIAN DRUGS • 2019

Dear Reader, Many of you would have noted the announcement of the establishment of a Centre by ICMR in New Delhi, in collaboration with a multinational pharmaceutical corporation to combat anti-microbial resistance (AMR). We see large full page advertisements with the words “AMR” in the front page of the daily news papers. These advertisements are the result of the efforts to draw the attention of all to the development of Anti-microbial resistance at a much faster pace than predicted. The action is noteworthy. However, it is difficult to comprehend how these advertisements will help to reduce AMR. While many more activities are being planned, it is hoped that the holistic approach being pursued will involve many more institutions and organizations. CDSCO has notified a separate schedule of drugs, Schedule H1 consisting of antibiotics, to ensure better prescription practices by medical professionals and the requirement that retailers maintain copies of the prescriptions served

European Food Safety Authority, European Centre for Disease Prevention and Control

EFSA Journal • 2022

Abstract Data on antimicrobial resistance (AMR) in zoonotic and indicator bacteria from humans, animals and food are collected annually by the EU Member States (MSs), jointly analysed by the EFSA and the ECDC and reported in a yearly EU Summary Report. The annual monitoring of AMR in animals and food within the EU is targeted at selected animal species corresponding to the reporting year. The 2020 monitoring specifically focussed on poultry and their derived carcases/meat, while the monitoring performed in 2019 specifically focused on fattening pigs and calves under 1 year of age, as well as their derived carcases/meat. Monitoring and reporting of AMR in 2019–2020 included data regarding Salmonella, Campylobacter and indicator E. coli isolates, as well as data obtained from the specific monitoring of presumptive ESBL‐/AmpC‐/carbapenemase‐producing E. coli isolates. Additionally, some MSs reported voluntary data on the occurrence of methicillin‐resistant Staphylococcus aureus in animals and food, with some countries also providing data on antimicrobial susceptibility. This report provides an overview of the main findings of the 2019–2020 harmonised AMR monitoring in the main food‐producing animal populations monitored, in carcase/meat samples and in humans. Where available, monitoring data obtained from pigs, calves, broilers, laying hens and turkeys, as well as from carcase/meat samples and humans were combined and compared at the EU level, with particular emphasis on multidrug resistance, complete susceptibility and combined resistance patterns to critically important antimicrobials, as well as Salmonella and E. coli isolates possessing ESBL‐/AmpC‐/carbapenemase phenotypes. The key outcome indicators for AMR in food‐producing animals, such as complete susceptibility to the harmonised panel of antimicrobials in E. coli and the prevalence of ESBL‐/AmpC‐producing E. coli have been specifically analysed over the period 2014–2020.

M. Florescu

Analytical Letters • 2019

It was a pleasure and a great honor to organize the Fifth International Conference on Analytical and Nanoanalytical Methods for Biomedical and Environmental Sciences, ICANMBES 2018, which was held from May 23–May 25, 2018, at Aula of Transilvania University of Brasov, Brasov, Romania. This event was organized by Transilvania University of Brasov in partnership with the European Biophysical Societies’ Association (EBSA), Bioelectrochemical Society (BES), Joint Institute for Nuclear Research, Romanian Society of Pure and Applied Biophysics, and under auspices of Romanian Minister of Education. The conference was designed as an international forum for effective exchange of knowledge and experience among researchers active in various theoretical and applied areas of natural science, medicine, environmental protection, and food safety. The fifth edition of the conference, IC-ANMBES 2018, covered different aspects of analytical and nano-analytical methods for Biomedical and Environmental Sciences, presented in the frame of 12 sections, fact which reveals the interdisciplinary nature of the conference:

Fuel Cells Bulletin • 2019

German-based SFC Energy has received a new follow-up order from an existing Asian defence customer, for additional units of the Jenny 600S portable fuel cell generator, the vehicle-based and stationary Emily 3000 power supply, and the SFC Power Manager 3G.

Siswantoro

Renewable Energy: Policy and Strategy • 2023

Developing renewable energy requires large investment funds, but the state financial scheme is not sufficient to meet the existing funding needs. On the other hand, the potential for cash waqf in Indonesia is quite large, but so far the collection and management of cash waqf in Indonesia is still not optimal. The focus of writing this work consists of three things, namely 1) Calculating the potential for cash waqf in Indonesia, 2) Describing the Cash Waqf Linked Sukuk (CWLS) model for renewable energy financing in Indonesia, and 3) Proposing strategies so that the CWLS model is maximized. The results of the work show that: First of all, the potential for cash waqf that can be collected and managed in Indonesia reaches IDR 52 trillion per year assuming that every productive-aged Muslim community in Indonesia sets aside 2.5% of their expenses for cash waqf. Second, the CWLS Model for renewable energy financing proposed in this work consists of 7 important steps and requires contributions from various parties (e.g wakif, nazhir, mauquf alaih, Ministry of finance, and others). Third, the strategy to maximize CWLS consists of four things including increasing Muslim community understanding and literacy regarding CWLS, increasing nazhir competence, using more sophisticated financial technology, and increasing transparency.

Rachmat Trijono

Renewable Energy: Policy and Strategy • 2023

The objective is to provide an overview of new renewable energy regulations and the scope of regulations related to new and renewable energy.

M H Mkrtchyan, L V Avetisyan

Journal of Physics: Conference Series • 2024

Abstract In various cases of electromechanical surface actions, the problems of surface control of the propagation of an electroactive transverse wave in a piezoelectric waveguide (piezoelectric class 6 mm of hexagonal symmetry) are considered. In both problems, one of the surfaces of the piezoelectric waveguide is mechanically free, and an electrical displacement normal to the surface acts. The second surface of the waveguide is firmly clamped and grounded, in one task, or there is a drift of electrons over the surface and there are no mechanical effects, in another task. The formulated initial boundary value problems are solved by the method of Fourier series. True electromechanical fields are built in the form of series of eigenmodes of electroacoustic oscillations in accordance with the harmonics of surface effects. Analytical and numerical calculations of the control process in cases of surface action are given.

Mohamed A. Mahmoud, Ahmed H. Al-Salman

International Petroleum Technology Conference • 2024

ABSTRACT Structural steel is widely used in marine environments because it is strong, readily available, easy to fabricate, and cost-effective. But steel is also subject to corrosion. Microbiologically influenced corrosion (MIC) plays a critical role in the pipeline corrosion process, caused by electrochemical reactions created by microorganisms that form ‘biofilms’ on immersed steel structures. The close monitoring of microbial growth is an essential process to protect the structural steel from biofilm formation. A semisolid growth media for quantitative and qualitative analysis of general aerobic bacteria (GAB) was studied and counterchecked with commercially available ready-made media Paddle tester double-sided slides, to prove the suitability to use the Total Coliform agar media with a two-day incubation at 35°C, for quantitative determination of GAB colonies at a specific pH range from 5.5 to 7.5. Several trials were conducted, including water streams at upstream facilities, rich with GAB and Coliform sources, and all the obtained results from both media were matched.

Mingming Qin, Qiuping Qian, Xiaoqing Gao et al.

Chemical Science • 2025

This BEET-redirecting strategy hijacks bacterial extracellular electron transfer to autonomously drive Cu 2+ → Cu + conversion and self-amplifying ˙OH cascades, enabling pathogen-specific sterilization without triggering bacterial resistance.