A redox-active monolayer on an optically transparent electrode constitutes a typical platform for spectroelectrochemical sensing.The necessity for its sophistication arises from the availability of multi-dimensional s...A redox-active monolayer on an optically transparent electrode constitutes a typical platform for spectroelectrochemical sensing.The necessity for its sophistication arises from the availability of multi-dimensional sensing signals.Simultaneous monitoring of the redox current and color change synchronized with the oxidation state change significantly enhances sen-sitivity and selectivity.This study aimed to elucidate the modification of an indium tin oxide(ITO)electrode with a viologen monolayer with an ordered orientation.Novel methods were developed to immobilize a viologen molecule bearing a car-boxyl group to form assembled monolayers through a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-car-bodiimide with N-hydroxy-succinimide(EDC/NHS).In the two methods of immobilization,one utilizes a two-step process to firstly form an aromatic siloxane base layer and subsequently attach the viologen derivative through an amide linkage by post-amidation.The other employs a direct ester linkage between the hydroxyl groups of the ITO surface and the car-boxyl group of the viologen derivative.The latter method was also applied to immobilize a ferrocenyl group at a very short distance from the ITO surface.Potential-modulated UV-visible transmission absorption spectral measurement techniques with oblique incidence of plane-polarized light were employed to determine the orientation of the longitudinal axis of the reduced form of the viologen.The frequency dependence data of the potential-modulated transmission absorption signals were utilized to analyze the electron transfer kinetics.The performance of the two viologen-modified electrodes was com-pared to that of an ITO modified by post-amidation to the most commonly used base layer prepared with 3-aminopropyl triethoxysilane.展开更多
The stable operation of supercapacitors at extremely low temperatures is crucial for applications in harsh envi-ronments.Unfortunately,conventional inorganic electrodes suffer from sluggish diffusion kinetics and poor...The stable operation of supercapacitors at extremely low temperatures is crucial for applications in harsh envi-ronments.Unfortunately,conventional inorganic electrodes suffer from sluggish diffusion kinetics and poor cycling stability for proton pseudocapacitors.Here,a redox-active polymer poly(1,5-diaminonaphthalene)is developed and synthesized as an ultrafast,high-mass loading,and durable pseudocapacitive anode.The charge storage of poly(1,5-diaminonaphthalene)depends on the reversible coordination reaction of the C¼N group with Hþ,which enables fast kinetics associated with surface-controlled reactions.The 3D-printed organic electrode delivers a remarkable areal capacitance(8.43 F cm^(-2)at 30.78 mg cm^(-2))and thickness-independent rate per-formance.Furthermore,the 3D-printed proton pseudocapacitor exhibits great low-temperature tolerance and delivers a high energy density of 0.44 mWh cm^(-2)at-60℃,as well as operates well even at-80℃.This work signifies that combining organic material design with 3D hierarchical network electrode construction can provide a promising solution for low-temperature-resistant supercapacitors.展开更多
Covalent organic frameworks(COFs)are promising materials for mitigating polysulfide shuttling in lithium-sulfur(Li-S)batteries,but enhancing their ability to convert polysulfides across a wide temperature range remain...Covalent organic frameworks(COFs)are promising materials for mitigating polysulfide shuttling in lithium-sulfur(Li-S)batteries,but enhancing their ability to convert polysulfides across a wide temperature range remains a challenge,Herein,we introduce a redox-active COF(RaCOF)that functions as both a physical barrier and a kinetic enhancer to improve the temperature adaptability of Li-S batteries,The RaCOF constructed from redox-active anthraquinone units accelerates polysulfide conversion kinetics through reversible C=O/C-OLi transformations within a voltage range of 1,7 to 2.8 V(vs.Li^(+)/Li),optimizing sulfur redox reactions in ether-based electrolytes.Unlike conventional COFs,RaCOF provides bidentate trapping of polysulfides,increasing binding energy and facilitating more effective polysulfide management.In-situ XRD and ToF-SIMS analyses confirm that RaCOF enhances polysulfide adsorption and promotes the transformation of lithium sulfide(Li_(2)S),leading to better sulfur cathode reutilization.Consequently,RaCOF-modified Li-S batteries demonstrate low self-discharge(4.0%decay over a 7-day rest),excellent wide-temperature performance(stable from-10 to+60℃),and high-rate cycling stability(94%capacity retention over 500 cycles at 5.0 C).This work offers valuable insights for designing COF structures aimed at achieving temperature-adaptive performance in rechargeable batteries.展开更多
Background： The redox status of intra-uterine growth retardation（IUGR） piglets post-weaning has been poorly studied.Methods： Newborns from twenty-four sows were weighted, weaned at 21 d and fed a starter diet unti...Background： The redox status of intra-uterine growth retardation（IUGR） piglets post-weaning has been poorly studied.Methods： Newborns from twenty-four sows were weighted, weaned at 21 d and fed a starter diet until sampling.Sampling was done at 14 d post-weaning. A piglet was defined as IUGR when its birth weight was 2 SD below the mean birth weight of the total population. At weaning, eighteen piglets with nearly equal body weight from each category（i.e. IUGR or normal birth weight（NBW） piglets） were selected and then allocated to two treatments,consisted of six replicates with each pen having three piglets.Results： Compared with NBW group, IUGR significantly decreased average daily gain（P 〈 0.001）, average daily feed intake（P = 0.003）, and feed efficiency（P 〈 0.001） of piglets during the first two weeks post-weaning. IUGR decreased the activities of total antioxidant capacity（P = 0.019）, total superoxide dismutase（T-SOD, P = 0.023）,and ceruloplasmin（P = 0.044） but increased the levels of malondialdehyde（P = 0.040） and protein carbonyl（P = 0.010） in plasma. Similarly, the decreased activities of T-SOD（P = 0.005）, copper- and zinc-containing superoxide dismutase（Cu/Zn-SOD, P = 0.002）, and catalase（P = 0.049） was observed in the liver of IUGR piglets than these of NBW piglets. IUGR decreased hepatic Cu/Zn-SOD activity（P = 0.023） per unit of Cu/Zn-SOD protein in piglets when compared with NBW piglets. In addition, IUGR piglets exhibited the decreases in accumulation of copper in both plasma（P = 0.001） and liver（P = 0.014）, as well as the concentrations of iron（P = 0.002） and zinc（P = 0.048） in liver. Compared with NBW, IUGR down-regulated m RNA expression of Cu/Zn-SOD（P = 0.021） in the liver of piglets.Conclusions： The results indicated that IUGR impaired antioxidant capacity and resulted in oxidative damage in fully weaned piglets, which might be associated with the decreased levels of redox-active trace minerals. This study highlights the importance of redox status in IUGR offspring and provides a rationale for alleviating oxidative damage by dietary interventions aiming to supplement trace minerals and to restore redox balance in the future.展开更多
The increasing demand of high-performance supercapacitors has aroused great interest in developing specific capacitance and energy density. Active carbon （AC） has attracted much attention as a promising electrode ma...The increasing demand of high-performance supercapacitors has aroused great interest in developing specific capacitance and energy density. Active carbon （AC） has attracted much attention as a promising electrode material for electric double-layer capacitors （EDLCs）. Here, a facile strategy has been employed to fabricate high-performance EDLCs using the surface-oxygen functionalized active carbon （FAC） as an electrode and 2 M KOH with K3Fe（CN）6 as an electrolyte. In this system, K3Fe（CN）6 was used as a redox additive to enhance the performance of EDLCs. A 38.5% increase in specific capacitance （207.7 F g-1） was achieved compared with the KOH electrolyte without adding K3Fe（CN）G （152.9 F g-1）, due to the synergistic effects between oxygenic functional groups and redox electrolyte. These findings provide an alternative route to improve the performance of EDLCs, which are promising candidates for the broad applications of high-performance supercapacitors.展开更多
A tetra（pyrid-2-yl）-pyrazine-bridged cyclometalated diosmium complex I（PF6）2 with two distal redox- active organic amine suhstituents has been synthesized and characterized. This complex displays four consecutive ...A tetra（pyrid-2-yl）-pyrazine-bridged cyclometalated diosmium complex I（PF6）2 with two distal redox- active organic amine suhstituents has been synthesized and characterized. This complex displays four consecutive and separated anodic redox waves at ＋0.24, ＋0.38, ＋0.64, and ＋0.71 V vs. Ag/AgCI. Upon stepwise oxidation, four-step absorption spectral changes in the visible to near-infrared region have been observed. The different redox states of I （1^2＋ through 1^6＋） can be distinguished by the significantly different absorption spectra in the visible and near-infrared region. DFT calculations of 1^3＋ show that the spin is delocalized on both osmium-amine components.展开更多
Three cobalt complexes bearing tunable,redox-active bipyridyl N-heterocyclic carbene(NHC)-based ligands have been studied for electrocatalytic hydrogen evolution from aqueous solutions.The effect of structural modific...Three cobalt complexes bearing tunable,redox-active bipyridyl N-heterocyclic carbene(NHC)-based ligands have been studied for electrocatalytic hydrogen evolution from aqueous solutions.The effect of structural modifications to the ligand framework is investigated across the catalyst series,which includes a non-macrocyclic derivative(1-Co)and 16-(2-Co)and 15-(3-Co)membered macrocycles.A structure-activity relationship is demonstrated,in which the macrocyclic complexes have greater activity compared to their non-macrocyclic counterpart with the most rigid catalyst,supported by the 15-membered macrocycle,performing best overall.Indeed,3-Co catalyzes H2 evolution from aqueous pH 4 acetate buffer with a Faradaic efficiency of 97%at a low overpotential of 330 mV.Mechanistic studies are consistent with formation of a cobalt-hydride species that is subsequently protonated to evolve H2 via a heterolytic pathway.展开更多
Three novel redox-active percec-type dendrons were synthesized by mucleophilic substitution reaction of 11-bromoundecyl ferrocene and substituted benzoate.All the resultant ferrocenyl-modified dendrons were confirmed ...Three novel redox-active percec-type dendrons were synthesized by mucleophilic substitution reaction of 11-bromoundecyl ferrocene and substituted benzoate.All the resultant ferrocenyl-modified dendrons were confirmed through FT-IR,NMR,and elemental analysis,etc.Furthermore,the thermal properties and electrochemical behavior of these dendrons were monitored with thermogravimetry analysis（TG）,differential scanning calorimetry（DSC）,polarized optical microscope（POM）,and cyclic voltammetry（CV）. Abound phase behavior and reversible electrochemical redox reaction process in the DMF solution of these dendrons was observed.展开更多
Thermal energy is abundantly available in our daily life and industrial production,and especially,low-grade heat is often regarded as a byproduct.Collecting and utilizing this ignored energy by low-cost and simple tec...Thermal energy is abundantly available in our daily life and industrial production,and especially,low-grade heat is often regarded as a byproduct.Collecting and utilizing this ignored energy by low-cost and simple technologies may become a smart countermeasure to relieve the energy crisis.Here,a unique device has been demonstrated to achieve high value-added conversion of low-grade heat by introducing redox-active organic alizarin(AZ)onto N-doped hollow carbon nanofibers(N–HCNF)surface.As-prepared N–HCNF/AZ can deliver a high specific capacitance of 514.3 F g^(-1)(at 1 A g^(-1))and an outstanding rate capability of 60.3%even at 50 A g^(-1).Meanwhile,the assembled symmetric proton capacitor can deliver a high energy density of 28.0 Wh kg^(-1) at 350.0 W kg^(-1) and a maximum power density of 35.0 kW kg^(-1) at 17.0 Wh kg^(-1).Significantly,the thermally chargeable proton capacitors can attain a surprisingly high Seebeck coefficient of 15.3 mV K^(-1) and a power factor of 6.02µW g^(-1).Taking advantage of such high performance,a satisfying open-circuit voltage of 481.0 mV with a temperature difference of 54 K is achieved.This research provides new insights into construction of high value-added energy systems requiring high electrochemical performances.展开更多
A novel macrocycle based on conformation-adaptive and electron-rich dihydrophenazine was designed and synthesized.On the one hand,the macrocycle showed host-vip interactions with tetracyanoquinodimethane(TCNQ)drivin...A novel macrocycle based on conformation-adaptive and electron-rich dihydrophenazine was designed and synthesized.On the one hand,the macrocycle showed host-vip interactions with tetracyanoquinodimethane(TCNQ)driving by charge transfer interaction between them.Meanwhile,host-vip complexation was accompanied by fluorescence quenching and conformational change of the macrocycle.On the other hand,the oxidation of the macrocycle resulted in its diradical cation analogue and induced the release of the vip molecule TCNQ,thereby accomplishing reversible binding dynamics.Therefore,this work wellillustrates the chemical and structural versatility of dihydrophenazine in the synthesis of macrocycles and their host-vip chemistry.展开更多
A challenge facing scientists is the rational synthesis of highly crystalline covalent organic frameworks(COFs),consisting of both n-type and p-type redox-active units,as cathodes for high-performance lithium-ion batt...A challenge facing scientists is the rational synthesis of highly crystalline covalent organic frameworks(COFs),consisting of both n-type and p-type redox-active units,as cathodes for high-performance lithium-ion batteries(LIBs).Herein,we apply reticular chemistry to regulate a COF platform with the kgm topology via an in-situ postsynthetic oxidation strategy.We integrate both n-type and p-type redox-active units into a resulting COF skeleton—TPDA-DQTA-COF,and this COF-based cathode shows an enhanced performance for LIBs compared to the parent TPDA-DMTA-COF.On account of dual redox-active units for PF6−/Li+costorage,the TPDADQTA-COF cathode presents the highly reversible capacity of 308 mAh g−1 at 0.2 A g^(−1) and the high energy density of 800 Wh kg^(−1).The long-term cycling experiment reveals a capacity retention of 91%after 200 cycles at a low current density of 0.5 A g^(−1).The combined Fourier transform infrared and X-ray photoelectron spectroscopy experiments suggest that the in-situ electrochemical oxidation from the C-OH to the C=O group of COFs occurs during the charging process.We believe our study demonstrates that the atomic-level modification of functional groups in COF-based cathode materials has a significant impact on the macroscopic performance of lithium-ion storage,clearly illustrating the structure-property relationship.展开更多
The network of microbial electron transfer can establish a syntrophic association of microbes by connecting interspecies metabolisms, and a variety of redox-active shuttles in environment have been proved to accelerat...The network of microbial electron transfer can establish a syntrophic association of microbes by connecting interspecies metabolisms, and a variety of redox-active shuttles in environment have been proved to accelerate the electron flow in a microbial community. Using humic substances as models, we investigated how different redox-active shuttles with different electrochemical properties influence interspecies electron transfer, and affect the shift of microbial communities. The co-culture of two species was constructed with supplements of humics, and the electron transfer between these two strains was found to be linked by humic acid with a wider window of redox potential and multi-peaks of redox reactions. Based on the shift of microbial composition, the humic substances with a wide potential window and multi-peaks of redox reactions for accepting and donating electrons could increase the biodiversity(Chao 1 and phylogenetic diversity) with a large extent. The mechanism by which redox-active shuttles mediate the microbial electron transfer network could facilitate our understanding of syntrophic interactions between microbes.展开更多
This paper reports a novel strategy for preparing redox-active electrolyte through introducing a redox-mediator(p-phenylenediamine,PPD) into KOH electrolyte for the application of ball-milled MnO 2-based supercapacito...This paper reports a novel strategy for preparing redox-active electrolyte through introducing a redox-mediator(p-phenylenediamine,PPD) into KOH electrolyte for the application of ball-milled MnO 2-based supercapacitors.The morphology and compositions of ball-milled MnO 2 were characterized using scanning electron microscopy(SEM) and X-ray diffraction(XRD).The electrochemical properties of the supercapacitor were evaluated by cyclic voltammetry(CV),galvanostatic charge-discharge(GCD),and electrochemical impedance spectroscopy(EIS) techniques.The introduction of p-phenylenediamine significantly improves the performance of the supercapacitor.The electrode specific capacitance of the supercapacitor is 325.24 F g-1,increased by 6.25 folds compared with that of the unmodified system(44.87 F g-1) at the same current density,and the energy density has nearly a 10-fold increase,reaching 10.12 Wh Kg-1.In addition,the supercapacitor exhibits good cycle-life stability.展开更多
Homeostasis of gut microbiota is extremely essential for maintaining nutrient metabolism and regulating immunological function.The increasing evidence suggests that inflammatory bowel disease(IBD)is strongly associate...Homeostasis of gut microbiota is extremely essential for maintaining nutrient metabolism and regulating immunological function.The increasing evidence suggests that inflammatory bowel disease(IBD)is strongly associated with dysregulation of gut microbiota.During activated inflammation,excessive reactive oxygen species(ROS)and reactive nitrogen species(RNS)produced by inflammatory cells play a detrimental role in regulating IBD and gut microbiota.ROS/RNS cause damage to the surrounding tissues,including nutrient absorption disorders,intestinal dysmotility and barrier dysfunction.Meanwhile,ROS/RNS provide terminal electron receptors for anaerobic respiration and support the bloom of facultative anaerobes,eventually causing gut microbiota dysbiosis.Redox-active nanoparticles(NPs)with catalytic properties or enzyme-like activities can effectively scavenge ROS/RNS,and selectively target inflamed sites via ultrasmall size-mediated enhanced permeation and retention(EPR)effect,showing great potential to regulate IBD and maintain the homeostasis of gut microbiota.In addition,the widespread application of NPs in commercial products 1 has increased their accumulation in healthy organisms,and the biological effects on normal microbiota resulting from long-term exposure of NPs to gastrointestinal tract also need attention.展开更多
A redox-active tetrazine moiety is immobilized within a metal-organic framework(MOF)aiming at targeted construction of a cathode with improved performance for lithium–oxygen batteries.A 1,2,4,5-tetrazine(Tz)functiona...A redox-active tetrazine moiety is immobilized within a metal-organic framework(MOF)aiming at targeted construction of a cathode with improved performance for lithium–oxygen batteries.A 1,2,4,5-tetrazine(Tz)functionalized ligand is used to construct a nanoporous MOF,Tz-Mg-MOF-74,in which the redox activity of the Tz moiety is retained.Combining the redox activity of Tz with the porous nature of a MOF produced a Tz-Mg-MOF-74-based cathode with significantly improved electrochemical performance.Specifically,the material has improved sustainable capacity with a lower overpotential compared with otherwise similar batteries without Tz and other reported MOF-based catalysts.The present approach productively integrates electrochemical activity derived from redox-active moieties and MOFs,and this combination opens a new avenue for the design of effective materials for energy storage and conversion.展开更多
The integration of redox-active sites into the skeleton of open-framework materials is an efficient strategy toward high-performance organic electrodes for energy storage devices.In this work,stepwise introduction of ...The integration of redox-active sites into the skeleton of open-framework materials is an efficient strategy toward high-performance organic electrodes for energy storage devices.In this work,stepwise introduction of ketone(KT)groups to the skeletons of isostructural two-dimensional(2D)covalent organic frameworks(COFs)was realized by the condensation of 2,4,6-triformylphloroglucinol(Tp,as nodes)with a series of ditopic diamines,which contained none,one,two,and four KT moieties in each linker units,respectively.The precise control of the redox functionalities at the molecular level,combined with regular built-in channels in these KT-Tp COFs endowed them with superior capacitances and excellent rate capabilities for energy storage.In particular,2KT-Tp COF and 4KT-Tp COF electrodes exhibited high capacitances of 256 and 583 F g−1 at a discharge rate of 0.2 A g−1,respectively,which outperformed most reported COF-based electrodes.More importantly,exceptional long-term cyclabilities(>92%capacitance retention)were achieved even after 20,000 cycles at a high current density of 5 A g−1 for these KT-Tp COFs.Our results demonstrated that orthoquinone moieties rendered enhanced performance than the redox COFs with isolated carbonyl groups.展开更多
Aqueous redox flow batteries,by using redox-active molecules dissolved in nonflammable water solutions as electrolytes,are a promising technology for grid-scale energy storage.Organic redox-active materials offer a ne...Aqueous redox flow batteries,by using redox-active molecules dissolved in nonflammable water solutions as electrolytes,are a promising technology for grid-scale energy storage.Organic redox-active materials offer a new opportunity for the construction of advanced flow batteries due to their advantages of potentially low cost,extensive structural diversity,tunable electrochemical properties,and high natural abundance.In this review,we present the emergence and development of organic redox-active materials for aqueous organic redox flow batteries(AORFBs),in particular,molecular engineering concepts and strategies of organic redox-active molecules.The typical design strategies based on organic redox species for high-capacity,high-stability,and high-voltage AORFBs are outlined and discussed.Molecular engineering of organic redox-active molecules for high aqueous solubility,high chemical/electrochemical stability,and multiple electron numbers as well as satisfactory redox potential gap between the redox pair is essential to realizing high-performance AORFBs.Beyond molecular engineering,the redoxtargeting strategy is an effective way to obtain high-capacity AORFBs.We further discuss and analyze the redox reaction mechanisms of organic redox species based on a series of electrochemical and spectroscopic approaches,and succinctly summarize the capacity degradation mechanisms of AORFBs.Furthermore,the current challenges,opportunities,and future directions of organic redox-active materials for AORFBs are presented in detail.展开更多
The performance of lithium-ion batteries(LIBs)can be effectively enhanced with functionalized separators.Herein,it is demonstrated that polydopamine-based redox-active(PRA)separators can provide additional capacity to...The performance of lithium-ion batteries(LIBs)can be effectively enhanced with functionalized separators.Herein,it is demonstrated that polydopamine-based redox-active(PRA)separators can provide additional capacity to that of typical anode materials,increase the volumetric capacity of the cell,as well as,decrease the cell resistance to yield an improved performance at higher cycling rates.The PRA separators,which are composed of a 2 mm thick electrically insulating nanocellulose fiber(NCF)layer and an 18 mm thick polydopamine(PDA)and carbon nanotube(CNT)containing redox-active layer,are readily produced using a facile paper-making process.The PRA separators are also easily wettable by commonly employed electrolytes(e.g.LP40)and exhibit a high dimensional stability.In addition,the pore structure endows the PRA separator with a high ionic conductivity(i.e.1.06 mS cm^(-1))that increases the rate performance of the cells.Due to the presence of the redox-active layer,Li_(4)Ti_(5)O_(12)(LTO)half-cells containing PRA separator were found to exhibit significantly higher capacities than the corresponding cells containing commercial separators.These results clearly show that the implementation of this type of redox-active separators constitutes a straightforward and effective way to increase the energy and power densities of LIBs.展开更多
Traditional in situ biogeochemical transformation suffers from competition among crucial microorganisms and inadequate formation of reactive minerals,thus leading to the accumulation of toxic intermediates.In this stu...Traditional in situ biogeochemical transformation suffers from competition among crucial microorganisms and inadequate formation of reactive minerals,thus leading to the accumulation of toxic intermediates.In this study,three regulation schemes were proposed to solve these problems from the perspective of engineering mode.Results showed intermittent injection mode effectively reduced the accumulation of toxic intermediates but the reduction rate of tetrachloroethylene was decreased.And periodical supplementation of carbon and sulfur sources accelerated the removal of tetrachloroethylene but failed to reduce the accumulation of toxic products.While,regular supplementation of sulfate effectively weakened the competition of methanogens and increased the iron sulfide proportion on the surface of the minerals,thus reducing the accumulation of toxicity.Based on the results,this study obtained an effective engineering approach for practical site application.In addition,the main forms of active minerals capable ofβ-eliminating contaminants during biogeochemical transformation were identified in this study,including FeS,FeS_(2),and Fe_(3)S_(4).Furthermore,the engineered regulatory mechanism of this study was summarized through the analysis of microbial community structure and mineral morphology.The amendment promotes the production of minerals and thus controls the transformation pathway of contaminants by altering the abundance of sulfate-reducing bacteria and dissimilatory iron reducing bacteria.This mechanism can provide a basis for subsequent theoretical studies.展开更多
Drinking water contamination by heavy metals,particularly chromium and arsenic oxyanions,is a severe challenge threatening humanity’s sustainable development.Electrochemically mediated water purification is gaining a...Drinking water contamination by heavy metals,particularly chromium and arsenic oxyanions,is a severe challenge threatening humanity’s sustainable development.Electrochemically mediated water purification is gaining attention due to its high uptake,rapid kinetics,modularity,and facile regeneration.Here,we designed a composite electrode by combining a redox-active/Faradaic polymer,poly(norbornene-diphenothiazine)(PNP_(2)),with carbon nanotubes(CNTs)–PNP_(2)-CNT.The PNP_(2)-CNT demonstrated exceptional pseudocapacitance behavior,resulting in significantly accelerated adsorption rates for dichromate(Cr(Ⅵ);0.008 gmg^(-1) min^(-1))and arsenite(As(Ⅲ);0.03 gmg^(-1) min^(-1)),surpassing reported materials by a margin of 3–200 times,while demonstrating a high adsorption capacity,666.3 and 612.4 mg g^(-1),respectively.Furthermore,it effectively converted As(Ⅲ)to the less toxic arsenate(As(Ⅴ))during adsorption and Cr(Ⅵ)to the less toxic chromium(Cr(Ⅲ))during desorption.This PNP_(2)-CNT system also showed significantly lower energy consumption,only 0.17%of the CNT control system.This study demonstrated for the first time the use of PNP_(2) redox-active polymers in the separation and conversion process,meeting the six criteria of high uptake,rapid kinetics,selectivity,stability,recyclability,and energy efficiency.This achievement expands the scope of advanced materials that address environmental concerns and make an impact by generating energy-and cost-effective water purification.展开更多
基金supports by the Grant-in-Aid of Scientific Research of Challenging Research(Exploratory)(JP23K17738)to TS from MEXT of Japanthe 41st grant of research from Nippon Sheet Glass Foundation for Materials Science and Engineering to TS.
文摘A redox-active monolayer on an optically transparent electrode constitutes a typical platform for spectroelectrochemical sensing.The necessity for its sophistication arises from the availability of multi-dimensional sensing signals.Simultaneous monitoring of the redox current and color change synchronized with the oxidation state change significantly enhances sen-sitivity and selectivity.This study aimed to elucidate the modification of an indium tin oxide(ITO)electrode with a viologen monolayer with an ordered orientation.Novel methods were developed to immobilize a viologen molecule bearing a car-boxyl group to form assembled monolayers through a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-car-bodiimide with N-hydroxy-succinimide(EDC/NHS).In the two methods of immobilization,one utilizes a two-step process to firstly form an aromatic siloxane base layer and subsequently attach the viologen derivative through an amide linkage by post-amidation.The other employs a direct ester linkage between the hydroxyl groups of the ITO surface and the car-boxyl group of the viologen derivative.The latter method was also applied to immobilize a ferrocenyl group at a very short distance from the ITO surface.Potential-modulated UV-visible transmission absorption spectral measurement techniques with oblique incidence of plane-polarized light were employed to determine the orientation of the longitudinal axis of the reduced form of the viologen.The frequency dependence data of the potential-modulated transmission absorption signals were utilized to analyze the electron transfer kinetics.The performance of the two viologen-modified electrodes was com-pared to that of an ITO modified by post-amidation to the most commonly used base layer prepared with 3-aminopropyl triethoxysilane.
基金supported by National Natural Science Foundation of China(52072173)International Science and Technology cooperation program of Jiangsu Province(SBZ2022000084)Funding for Outstanding Doctoral Dissertation in NUAA(BCXJ23-10).
文摘The stable operation of supercapacitors at extremely low temperatures is crucial for applications in harsh envi-ronments.Unfortunately,conventional inorganic electrodes suffer from sluggish diffusion kinetics and poor cycling stability for proton pseudocapacitors.Here,a redox-active polymer poly(1,5-diaminonaphthalene)is developed and synthesized as an ultrafast,high-mass loading,and durable pseudocapacitive anode.The charge storage of poly(1,5-diaminonaphthalene)depends on the reversible coordination reaction of the C¼N group with Hþ,which enables fast kinetics associated with surface-controlled reactions.The 3D-printed organic electrode delivers a remarkable areal capacitance(8.43 F cm^(-2)at 30.78 mg cm^(-2))and thickness-independent rate per-formance.Furthermore,the 3D-printed proton pseudocapacitor exhibits great low-temperature tolerance and delivers a high energy density of 0.44 mWh cm^(-2)at-60℃,as well as operates well even at-80℃.This work signifies that combining organic material design with 3D hierarchical network electrode construction can provide a promising solution for low-temperature-resistant supercapacitors.
基金funding supporting from the National Natural Science Foundation of China(22309003,22379001)the Natural Science Research Project of Anhui Province Education Department(2023AH051119)+3 种基金the open project funding from Shanghai Key Laboratory of Multi phase Materials Chemical Engineering(MMCE2024001)the National Key Research and Development Program of China(2022YFB2402201)the Shanghai Pilot Program for Basic Research-Fudan University 21TQ1400100(21TQ009)the Fundamental Research Funds for the Central Universities(20720220010).
文摘Covalent organic frameworks(COFs)are promising materials for mitigating polysulfide shuttling in lithium-sulfur(Li-S)batteries,but enhancing their ability to convert polysulfides across a wide temperature range remains a challenge,Herein,we introduce a redox-active COF(RaCOF)that functions as both a physical barrier and a kinetic enhancer to improve the temperature adaptability of Li-S batteries,The RaCOF constructed from redox-active anthraquinone units accelerates polysulfide conversion kinetics through reversible C=O/C-OLi transformations within a voltage range of 1,7 to 2.8 V(vs.Li^(+)/Li),optimizing sulfur redox reactions in ether-based electrolytes.Unlike conventional COFs,RaCOF provides bidentate trapping of polysulfides,increasing binding energy and facilitating more effective polysulfide management.In-situ XRD and ToF-SIMS analyses confirm that RaCOF enhances polysulfide adsorption and promotes the transformation of lithium sulfide(Li_(2)S),leading to better sulfur cathode reutilization.Consequently,RaCOF-modified Li-S batteries demonstrate low self-discharge(4.0%decay over a 7-day rest),excellent wide-temperature performance(stable from-10 to+60℃),and high-rate cycling stability(94%capacity retention over 500 cycles at 5.0 C).This work offers valuable insights for designing COF structures aimed at achieving temperature-adaptive performance in rechargeable batteries.
基金supported by the National Natural Science Foundation of China (31272454)
文摘Background： The redox status of intra-uterine growth retardation（IUGR） piglets post-weaning has been poorly studied.Methods： Newborns from twenty-four sows were weighted, weaned at 21 d and fed a starter diet until sampling.Sampling was done at 14 d post-weaning. A piglet was defined as IUGR when its birth weight was 2 SD below the mean birth weight of the total population. At weaning, eighteen piglets with nearly equal body weight from each category（i.e. IUGR or normal birth weight（NBW） piglets） were selected and then allocated to two treatments,consisted of six replicates with each pen having three piglets.Results： Compared with NBW group, IUGR significantly decreased average daily gain（P 〈 0.001）, average daily feed intake（P = 0.003）, and feed efficiency（P 〈 0.001） of piglets during the first two weeks post-weaning. IUGR decreased the activities of total antioxidant capacity（P = 0.019）, total superoxide dismutase（T-SOD, P = 0.023）,and ceruloplasmin（P = 0.044） but increased the levels of malondialdehyde（P = 0.040） and protein carbonyl（P = 0.010） in plasma. Similarly, the decreased activities of T-SOD（P = 0.005）, copper- and zinc-containing superoxide dismutase（Cu/Zn-SOD, P = 0.002）, and catalase（P = 0.049） was observed in the liver of IUGR piglets than these of NBW piglets. IUGR decreased hepatic Cu/Zn-SOD activity（P = 0.023） per unit of Cu/Zn-SOD protein in piglets when compared with NBW piglets. In addition, IUGR piglets exhibited the decreases in accumulation of copper in both plasma（P = 0.001） and liver（P = 0.014）, as well as the concentrations of iron（P = 0.002） and zinc（P = 0.048） in liver. Compared with NBW, IUGR down-regulated m RNA expression of Cu/Zn-SOD（P = 0.021） in the liver of piglets.Conclusions： The results indicated that IUGR impaired antioxidant capacity and resulted in oxidative damage in fully weaned piglets, which might be associated with the decreased levels of redox-active trace minerals. This study highlights the importance of redox status in IUGR offspring and provides a rationale for alleviating oxidative damage by dietary interventions aiming to supplement trace minerals and to restore redox balance in the future.
基金supported by grants from the National Natural Science Foundation of China(Nos.21606033,21376034,21506086)
文摘The increasing demand of high-performance supercapacitors has aroused great interest in developing specific capacitance and energy density. Active carbon （AC） has attracted much attention as a promising electrode material for electric double-layer capacitors （EDLCs）. Here, a facile strategy has been employed to fabricate high-performance EDLCs using the surface-oxygen functionalized active carbon （FAC） as an electrode and 2 M KOH with K3Fe（CN）6 as an electrolyte. In this system, K3Fe（CN）6 was used as a redox additive to enhance the performance of EDLCs. A 38.5% increase in specific capacitance （207.7 F g-1） was achieved compared with the KOH electrolyte without adding K3Fe（CN）G （152.9 F g-1）, due to the synergistic effects between oxygenic functional groups and redox electrolyte. These findings provide an alternative route to improve the performance of EDLCs, which are promising candidates for the broad applications of high-performance supercapacitors.
基金the National Natural Science Foundation of China (Nos.21271176,91227104,21472196,and 21221002)the National Basic Research 973 program of China (No.2011CB932301)+1 种基金the Ministry of Science and Technology of China (No.2012YQ120060)the Strategic Priority Research Program of the Chinese Academy of Sciences (No.XDB 12010400) for funding support
文摘A tetra（pyrid-2-yl）-pyrazine-bridged cyclometalated diosmium complex I（PF6）2 with two distal redox- active organic amine suhstituents has been synthesized and characterized. This complex displays four consecutive and separated anodic redox waves at ＋0.24, ＋0.38, ＋0.64, and ＋0.71 V vs. Ag/AgCI. Upon stepwise oxidation, four-step absorption spectral changes in the visible to near-infrared region have been observed. The different redox states of I （1^2＋ through 1^6＋） can be distinguished by the significantly different absorption spectra in the visible and near-infrared region. DFT calculations of 1^3＋ show that the spin is delocalized on both osmium-amine components.
文摘Three cobalt complexes bearing tunable,redox-active bipyridyl N-heterocyclic carbene(NHC)-based ligands have been studied for electrocatalytic hydrogen evolution from aqueous solutions.The effect of structural modifications to the ligand framework is investigated across the catalyst series,which includes a non-macrocyclic derivative(1-Co)and 16-(2-Co)and 15-(3-Co)membered macrocycles.A structure-activity relationship is demonstrated,in which the macrocyclic complexes have greater activity compared to their non-macrocyclic counterpart with the most rigid catalyst,supported by the 15-membered macrocycle,performing best overall.Indeed,3-Co catalyzes H2 evolution from aqueous pH 4 acetate buffer with a Faradaic efficiency of 97%at a low overpotential of 330 mV.Mechanistic studies are consistent with formation of a cobalt-hydride species that is subsequently protonated to evolve H2 via a heterolytic pathway.
基金The financial support from the NSFC(No.50873037)China Postdoctoral Science Foundation(No.20100470908, 201104349)the NSF of Guangdong Province(No.10451064101005118) is gratefully acknowledged
文摘Three novel redox-active percec-type dendrons were synthesized by mucleophilic substitution reaction of 11-bromoundecyl ferrocene and substituted benzoate.All the resultant ferrocenyl-modified dendrons were confirmed through FT-IR,NMR,and elemental analysis,etc.Furthermore,the thermal properties and electrochemical behavior of these dendrons were monitored with thermogravimetry analysis（TG）,differential scanning calorimetry（DSC）,polarized optical microscope（POM）,and cyclic voltammetry（CV）. Abound phase behavior and reversible electrochemical redox reaction process in the DMF solution of these dendrons was observed.
基金This work was supported by the National Natural Science Foundation of China(U1802256,21773118)Leading Edge Technology of Jiangsu Province(BK20202008)+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX21_0204)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Thermal energy is abundantly available in our daily life and industrial production,and especially,low-grade heat is often regarded as a byproduct.Collecting and utilizing this ignored energy by low-cost and simple technologies may become a smart countermeasure to relieve the energy crisis.Here,a unique device has been demonstrated to achieve high value-added conversion of low-grade heat by introducing redox-active organic alizarin(AZ)onto N-doped hollow carbon nanofibers(N–HCNF)surface.As-prepared N–HCNF/AZ can deliver a high specific capacitance of 514.3 F g^(-1)(at 1 A g^(-1))and an outstanding rate capability of 60.3%even at 50 A g^(-1).Meanwhile,the assembled symmetric proton capacitor can deliver a high energy density of 28.0 Wh kg^(-1) at 350.0 W kg^(-1) and a maximum power density of 35.0 kW kg^(-1) at 17.0 Wh kg^(-1).Significantly,the thermally chargeable proton capacitors can attain a surprisingly high Seebeck coefficient of 15.3 mV K^(-1) and a power factor of 6.02µW g^(-1).Taking advantage of such high performance,a satisfying open-circuit voltage of 481.0 mV with a temperature difference of 54 K is achieved.This research provides new insights into construction of high value-added energy systems requiring high electrochemical performances.
基金supported by the NSFC,China(No.22071061)the Shanghai Natural Science Foundation(No.22ZR1420600).
文摘A novel macrocycle based on conformation-adaptive and electron-rich dihydrophenazine was designed and synthesized.On the one hand,the macrocycle showed host-vip interactions with tetracyanoquinodimethane(TCNQ)driving by charge transfer interaction between them.Meanwhile,host-vip complexation was accompanied by fluorescence quenching and conformational change of the macrocycle.On the other hand,the oxidation of the macrocycle resulted in its diradical cation analogue and induced the release of the vip molecule TCNQ,thereby accomplishing reversible binding dynamics.Therefore,this work wellillustrates the chemical and structural versatility of dihydrophenazine in the synthesis of macrocycles and their host-vip chemistry.
基金financial support by the National Natural Science Foundation of China(grant nos.22201247 and 22105028)startup funding from Zhejiang University and Natural Science Foundation of Chongqing(cstc2021jcyj-msxmX0572)+1 种基金the National Facility for Protein Science in Shanghai(NFPS),Shanghai Advanced Research Institute,Chinese Academy of Sciences,for providing technical support in X-ray diffraction data collection and analysis(grant no.2023-NFPS-PT-500479)We thank the Chemistry Instrumentation Center Zhejiang University for the technical support.
文摘A challenge facing scientists is the rational synthesis of highly crystalline covalent organic frameworks(COFs),consisting of both n-type and p-type redox-active units,as cathodes for high-performance lithium-ion batteries(LIBs).Herein,we apply reticular chemistry to regulate a COF platform with the kgm topology via an in-situ postsynthetic oxidation strategy.We integrate both n-type and p-type redox-active units into a resulting COF skeleton—TPDA-DQTA-COF,and this COF-based cathode shows an enhanced performance for LIBs compared to the parent TPDA-DMTA-COF.On account of dual redox-active units for PF6−/Li+costorage,the TPDADQTA-COF cathode presents the highly reversible capacity of 308 mAh g−1 at 0.2 A g^(−1) and the high energy density of 800 Wh kg^(−1).The long-term cycling experiment reveals a capacity retention of 91%after 200 cycles at a low current density of 0.5 A g^(−1).The combined Fourier transform infrared and X-ray photoelectron spectroscopy experiments suggest that the in-situ electrochemical oxidation from the C-OH to the C=O group of COFs occurs during the charging process.We believe our study demonstrates that the atomic-level modification of functional groups in COF-based cathode materials has a significant impact on the macroscopic performance of lithium-ion storage,clearly illustrating the structure-property relationship.
基金supported by the National Natural Science Foundation of China(Grant Nos.41471260,21777155)
文摘The network of microbial electron transfer can establish a syntrophic association of microbes by connecting interspecies metabolisms, and a variety of redox-active shuttles in environment have been proved to accelerate the electron flow in a microbial community. Using humic substances as models, we investigated how different redox-active shuttles with different electrochemical properties influence interspecies electron transfer, and affect the shift of microbial communities. The co-culture of two species was constructed with supplements of humics, and the electron transfer between these two strains was found to be linked by humic acid with a wider window of redox potential and multi-peaks of redox reactions. Based on the shift of microbial composition, the humic substances with a wide potential window and multi-peaks of redox reactions for accepting and donating electrons could increase the biodiversity(Chao 1 and phylogenetic diversity) with a large extent. The mechanism by which redox-active shuttles mediate the microbial electron transfer network could facilitate our understanding of syntrophic interactions between microbes.
基金supported by the National High Technology Research and Development Program of China (2009AA03Z217)the National Natural Science Foundation of China (90922028,50842027)the Key Project of Ministry of Education of China (211204)
文摘This paper reports a novel strategy for preparing redox-active electrolyte through introducing a redox-mediator(p-phenylenediamine,PPD) into KOH electrolyte for the application of ball-milled MnO 2-based supercapacitors.The morphology and compositions of ball-milled MnO 2 were characterized using scanning electron microscopy(SEM) and X-ray diffraction(XRD).The electrochemical properties of the supercapacitor were evaluated by cyclic voltammetry(CV),galvanostatic charge-discharge(GCD),and electrochemical impedance spectroscopy(EIS) techniques.The introduction of p-phenylenediamine significantly improves the performance of the supercapacitor.The electrode specific capacitance of the supercapacitor is 325.24 F g-1,increased by 6.25 folds compared with that of the unmodified system(44.87 F g-1) at the same current density,and the energy density has nearly a 10-fold increase,reaching 10.12 Wh Kg-1.In addition,the supercapacitor exhibits good cycle-life stability.
基金supported by the National Natural Science Foundation of China(Nos.91859101,81971744,U1932107,and 81471786)the National Natural Science Foundation of Tianjin(No.19JCZDJC34000)the Innovation Foundation of Tianjin University.
文摘Homeostasis of gut microbiota is extremely essential for maintaining nutrient metabolism and regulating immunological function.The increasing evidence suggests that inflammatory bowel disease(IBD)is strongly associated with dysregulation of gut microbiota.During activated inflammation,excessive reactive oxygen species(ROS)and reactive nitrogen species(RNS)produced by inflammatory cells play a detrimental role in regulating IBD and gut microbiota.ROS/RNS cause damage to the surrounding tissues,including nutrient absorption disorders,intestinal dysmotility and barrier dysfunction.Meanwhile,ROS/RNS provide terminal electron receptors for anaerobic respiration and support the bloom of facultative anaerobes,eventually causing gut microbiota dysbiosis.Redox-active nanoparticles(NPs)with catalytic properties or enzyme-like activities can effectively scavenge ROS/RNS,and selectively target inflamed sites via ultrasmall size-mediated enhanced permeation and retention(EPR)effect,showing great potential to regulate IBD and maintain the homeostasis of gut microbiota.In addition,the widespread application of NPs in commercial products 1 has increased their accumulation in healthy organisms,and the biological effects on normal microbiota resulting from long-term exposure of NPs to gastrointestinal tract also need attention.
基金supported by the NSFC(nos.21421001,21531005,21905142,and 21671112)the Program of Introducing Talents of Discipline to Universities(no.B18030)+1 种基金the Natural Science Fund of Tianjin(nos.19JCZDJC37200 and 19JCQNJC02600)China.The authors thank Professor Brian Space(University of South Florida,Tampa,FL)for discussion and help.
文摘A redox-active tetrazine moiety is immobilized within a metal-organic framework(MOF)aiming at targeted construction of a cathode with improved performance for lithium–oxygen batteries.A 1,2,4,5-tetrazine(Tz)functionalized ligand is used to construct a nanoporous MOF,Tz-Mg-MOF-74,in which the redox activity of the Tz moiety is retained.Combining the redox activity of Tz with the porous nature of a MOF produced a Tz-Mg-MOF-74-based cathode with significantly improved electrochemical performance.Specifically,the material has improved sustainable capacity with a lower overpotential compared with otherwise similar batteries without Tz and other reported MOF-based catalysts.The present approach productively integrates electrochemical activity derived from redox-active moieties and MOFs,and this combination opens a new avenue for the design of effective materials for energy storage and conversion.
基金supported financially by the National Key Research and Development Program of China(2017YFA0207500)National Natural Science Foundation of China(51973153)+1 种基金and Natural Science Foundation of Tianjin City(17JCJQJC44600).C.Peng is grateful for the funding from the National Natural Science Foundation of China(21875141),Shanghai Pujiang Program(18PJ1409000)and the Opening Project of State Key Laboratory of Advanced Chemical Power Sources(SKLACPS-C-23).
文摘The integration of redox-active sites into the skeleton of open-framework materials is an efficient strategy toward high-performance organic electrodes for energy storage devices.In this work,stepwise introduction of ketone(KT)groups to the skeletons of isostructural two-dimensional(2D)covalent organic frameworks(COFs)was realized by the condensation of 2,4,6-triformylphloroglucinol(Tp,as nodes)with a series of ditopic diamines,which contained none,one,two,and four KT moieties in each linker units,respectively.The precise control of the redox functionalities at the molecular level,combined with regular built-in channels in these KT-Tp COFs endowed them with superior capacitances and excellent rate capabilities for energy storage.In particular,2KT-Tp COF and 4KT-Tp COF electrodes exhibited high capacitances of 256 and 583 F g−1 at a discharge rate of 0.2 A g−1,respectively,which outperformed most reported COF-based electrodes.More importantly,exceptional long-term cyclabilities(>92%capacitance retention)were achieved even after 20,000 cycles at a high current density of 5 A g−1 for these KT-Tp COFs.Our results demonstrated that orthoquinone moieties rendered enhanced performance than the redox COFs with isolated carbonyl groups.
基金Scientific and Technological Innovation Special Fund for Carbon Peak and Carbon Neutrality of Jiangsu Province,Grant/Award Number:BK20220008Suzhou Gusu Leading Talent Program of Science and Technology Innovation and Entrepreneurship in Wujiang District,Grant/Award Number:ZXL2021273+5 种基金Central University Basic Research Fund of China,Grant/Award Numbers:020514380266,020514380272,020514380274Natural Science Foundation of Jiangsu Province,Grant/Award Number:BK20200306Research Grants Council of the Hong Kong Special Administrative Region,China,Grant/Award Number:T23‐601/17‐RNational Natural Science Foundation of China,Grant/Award Numbers:21872069,22022505Nanjing International Collaboration Research Program,Grant/Award Numbers:202201007,2022SX00000955National Key R&D Program of China,Grant/Award Number:2017YFA0208200。
文摘Aqueous redox flow batteries,by using redox-active molecules dissolved in nonflammable water solutions as electrolytes,are a promising technology for grid-scale energy storage.Organic redox-active materials offer a new opportunity for the construction of advanced flow batteries due to their advantages of potentially low cost,extensive structural diversity,tunable electrochemical properties,and high natural abundance.In this review,we present the emergence and development of organic redox-active materials for aqueous organic redox flow batteries(AORFBs),in particular,molecular engineering concepts and strategies of organic redox-active molecules.The typical design strategies based on organic redox species for high-capacity,high-stability,and high-voltage AORFBs are outlined and discussed.Molecular engineering of organic redox-active molecules for high aqueous solubility,high chemical/electrochemical stability,and multiple electron numbers as well as satisfactory redox potential gap between the redox pair is essential to realizing high-performance AORFBs.Beyond molecular engineering,the redoxtargeting strategy is an effective way to obtain high-capacity AORFBs.We further discuss and analyze the redox reaction mechanisms of organic redox species based on a series of electrochemical and spectroscopic approaches,and succinctly summarize the capacity degradation mechanisms of AORFBs.Furthermore,the current challenges,opportunities,and future directions of organic redox-active materials for AORFBs are presented in detail.
基金The work is financially supported by The Swedish Energy Agency(i.e.the TriLi project and project 2017-013543)as well as StandUp for Energy.
文摘The performance of lithium-ion batteries(LIBs)can be effectively enhanced with functionalized separators.Herein,it is demonstrated that polydopamine-based redox-active(PRA)separators can provide additional capacity to that of typical anode materials,increase the volumetric capacity of the cell,as well as,decrease the cell resistance to yield an improved performance at higher cycling rates.The PRA separators,which are composed of a 2 mm thick electrically insulating nanocellulose fiber(NCF)layer and an 18 mm thick polydopamine(PDA)and carbon nanotube(CNT)containing redox-active layer,are readily produced using a facile paper-making process.The PRA separators are also easily wettable by commonly employed electrolytes(e.g.LP40)and exhibit a high dimensional stability.In addition,the pore structure endows the PRA separator with a high ionic conductivity(i.e.1.06 mS cm^(-1))that increases the rate performance of the cells.Due to the presence of the redox-active layer,Li_(4)Ti_(5)O_(12)(LTO)half-cells containing PRA separator were found to exhibit significantly higher capacities than the corresponding cells containing commercial separators.These results clearly show that the implementation of this type of redox-active separators constitutes a straightforward and effective way to increase the energy and power densities of LIBs.
基金supported by the National Natural Science Foundation of China(No.42277057).
文摘Traditional in situ biogeochemical transformation suffers from competition among crucial microorganisms and inadequate formation of reactive minerals,thus leading to the accumulation of toxic intermediates.In this study,three regulation schemes were proposed to solve these problems from the perspective of engineering mode.Results showed intermittent injection mode effectively reduced the accumulation of toxic intermediates but the reduction rate of tetrachloroethylene was decreased.And periodical supplementation of carbon and sulfur sources accelerated the removal of tetrachloroethylene but failed to reduce the accumulation of toxic products.While,regular supplementation of sulfate effectively weakened the competition of methanogens and increased the iron sulfide proportion on the surface of the minerals,thus reducing the accumulation of toxicity.Based on the results,this study obtained an effective engineering approach for practical site application.In addition,the main forms of active minerals capable ofβ-eliminating contaminants during biogeochemical transformation were identified in this study,including FeS,FeS_(2),and Fe_(3)S_(4).Furthermore,the engineered regulatory mechanism of this study was summarized through the analysis of microbial community structure and mineral morphology.The amendment promotes the production of minerals and thus controls the transformation pathway of contaminants by altering the abundance of sulfate-reducing bacteria and dissimilatory iron reducing bacteria.This mechanism can provide a basis for subsequent theoretical studies.
基金supported by the Research Grants Council of the Hong Kong SAR Government(Early Career Scheme,#26309420,and General Research Fund,#16306921 and#16306022)the Department of Chemical and Biomolecular Engineering,HKUST(startup funding)+1 种基金sponsored by the Shanghai Jiao Tong University High-End Computing Center.Y.W.would like to thank the support from the National Natural Science Foundation of China(No.52102183,No.52281240409)the Natural Science Foundation of Shanghai(No.22ZR1433400).
文摘Drinking water contamination by heavy metals,particularly chromium and arsenic oxyanions,is a severe challenge threatening humanity’s sustainable development.Electrochemically mediated water purification is gaining attention due to its high uptake,rapid kinetics,modularity,and facile regeneration.Here,we designed a composite electrode by combining a redox-active/Faradaic polymer,poly(norbornene-diphenothiazine)(PNP_(2)),with carbon nanotubes(CNTs)–PNP_(2)-CNT.The PNP_(2)-CNT demonstrated exceptional pseudocapacitance behavior,resulting in significantly accelerated adsorption rates for dichromate(Cr(Ⅵ);0.008 gmg^(-1) min^(-1))and arsenite(As(Ⅲ);0.03 gmg^(-1) min^(-1)),surpassing reported materials by a margin of 3–200 times,while demonstrating a high adsorption capacity,666.3 and 612.4 mg g^(-1),respectively.Furthermore,it effectively converted As(Ⅲ)to the less toxic arsenate(As(Ⅴ))during adsorption and Cr(Ⅵ)to the less toxic chromium(Cr(Ⅲ))during desorption.This PNP_(2)-CNT system also showed significantly lower energy consumption,only 0.17%of the CNT control system.This study demonstrated for the first time the use of PNP_(2) redox-active polymers in the separation and conversion process,meeting the six criteria of high uptake,rapid kinetics,selectivity,stability,recyclability,and energy efficiency.This achievement expands the scope of advanced materials that address environmental concerns and make an impact by generating energy-and cost-effective water purification.
