Zwitterions(ZIs)are considered as an ideal,novel ionic conductive medium due to their high dipole moment and good solubility of lithium salts.However,the strong interactions between ZIs and Li^(+)severely hinder Li^(+...Zwitterions(ZIs)are considered as an ideal,novel ionic conductive medium due to their high dipole moment and good solubility of lithium salts.However,the strong interactions between ZIs and Li^(+)severely hinder Li^(+)migration.Herein,a quasi-solid electrolyte(MSQSE-2Na)was fabricated by adding sodium bis(fluorosulfonyl)imide(NaFSI)to sulfobetaine methacrylate(SBMA,a ZI)based polymerization system.Na^(+)occupies the–SO_(3)^(-)site in SBMA prior to Li^(+),which weakens the self-crosslinking of SBMA and frees the Li^(+)bound to the polymer segments.Thus,the polymer conformation of MSQSE-2Na changes to a relaxed,homogeneous"sea-island"type.Meanwhile,Na^(+),due to its electron-withdrawing effect,decreases the electron cloud density of the polymer segments,building a weakly coordinated environment in MSQSE-2Na.Consequently,MSQSE-2Na exhibits excellent ionic conductivity of 7.38×10^(-4)S cm^(-1)and a high Li^(+)transference number of 0.632 at 25℃.The(-)Li|MSQSE-2Na|Li(+)cells exhibit super stability,sustaining operation for over 6182h.The(-)Li|MSQSE-2Na|LiFePO_(4)(+)cells demonstrate outstanding charge/discharge reversibility with a Coulombic efficiency exceeding 99.9%over 270 cycles(≈4500 h),with a capacity retention of 70.0%.This work proposes a new design concept for regulating the polymer conformation and charge characteristics through competitive coordination,thereby advancing the application of ZI-based polymer electrolytes in lithium metal batteries.展开更多
The sluggish bidirectional conversion rate between Li_(2)S_(n)(2≤n≤4)and Li_(2)S,coupled with the uncontrolled deposition of Li_(2)S,significantly impedes the realization of high-performance lithium-sulfur batteries...The sluggish bidirectional conversion rate between Li_(2)S_(n)(2≤n≤4)and Li_(2)S,coupled with the uncontrolled deposition of Li_(2)S,significantly impedes the realization of high-performance lithium-sulfur batteries(LSBs).In this study,a metal-organic framework was employed as a precursor for the synthesis of a CoO_(x)-CeO_(2-y)/C(0<x<3/2,0<y<1/2)heterojunction via pyrolysis,which was subsequently introduced onto the cathode side of the polypropylene(PP)separator in LSBs.The modification of CoO_(x)-CeO_(2-y)/C enhances the kinetics of converting of Li_(2)S_(n)to Li_(2)S during the discharge process.The Tafel slope for the Li_(2)S deposition reaction is reduced to 52.1 mV/dec,representing a 56.6%decrease compared to LSBs with bare PP separator.Conversely,during the charging process,the modification lowers the energy barrier for the Li_(2)S decomposition reaction,with the activation energy reduced to 6.12 kJ/mol,indicating a 70.3%decrease relative to LSBs with PP separator only.Consequently,more Li_(2)S is promoted to undergo decomposition.The CoO_(x)-CeO_(2-y)/C heterojunction facilitates uniform deposition of Li_(2)S,featuringfine particles and a uniform distribution,after brief potentiostatic charging for decomposition,thereby effectively mitigating the deactivation of sulfur species.Thanks to the enhanced bidirectional conversion of lithium polysulfides(LiPS)facilitated by the CoO_(x)-CeO_(2-y)/C modification layer,the(-)Li|CoO_(x)-CeO_(2-y)/C@PPIS(+)coin cell maintains a Coulombic efficiency of 90.4%after 500 cycles at a current density of 1 C,exhibiting a low capacity-decay rate of only 0.081%per cycle,thereby demonstrating excellent long-cycle stability.展开更多
Solid-state polymer electrolytes(SPEs) capable of withstanding high voltage are considered to be key for next-generation energy storage devices with inherent safety as well as high energy density.This study involves t...Solid-state polymer electrolytes(SPEs) capable of withstanding high voltage are considered to be key for next-generation energy storage devices with inherent safety as well as high energy density.This study involves the rational design of solid-state-C≡N functionalized P(VEC_1-CEA_(0.3))/LiTFSI@CE SPEs and its synthesis by in-situ free radical polymerization of vinyl ethylene carbonate(VEC) and 2-cyanoethyl acrylate(CEA).In situ polymerization yields electrode/electrolyte interfaces with low interfacial resistance,forming a stable SEI layer enriched with LiF,Li_(3)N,and RCOOLi,ensuring stable Li plating/stripping for over 1400 h.The-C≡N moiety renders the αH on the adjacent αC positively charged,thereby endowing it with the capability to anchor TFSI^(-).Simultaneously,the incorporation of-C≡N moiety diminishes the electron-donating ability of the C=O,C-O-C,and-C≡N functional groups,facilitating not only the ion conductivity enhancement but also a more rapid Li^(+)migration proved by DFT theoretical calculations and Raman spectroscopy.At room temperature,t_(Li+) of 0.60 for P(VEC_1-CEA_(0.3))/LiTFSI@CE SPEs is achieved when the ionic conductivity σ_(Li+)is 2.63×10^(-4) S cm^(-1) and the electrochemical window is expanded to5.0 V.Both coin cells with high-areal-loading cathodes and the 6.5-mAh pouch cell,exhibit stable charge/discharge cycling.At 25℃,the 4.45-V Li|P(VEC_1-CEA_(0.3))/LiTFSI@CE|LiCoO_(2) battery performs stable cycling over 200 cycles at 0.2 C,with a capacity retention of 82.1%.展开更多
Sodium-ion hybrid capacitor(SIHC)is one of the most promising alternatives for large-scale energy storage due to its high energy and power densities,natural abundance,and low cost.However,overcoming the imbalance betw...Sodium-ion hybrid capacitor(SIHC)is one of the most promising alternatives for large-scale energy storage due to its high energy and power densities,natural abundance,and low cost.However,overcoming the imbalance between slow Na^(+)reaction kinetics of battery-type anodes and rapid ion adsorption/desorption of capacitive cathodes is a significant challenge.Here,we propose the high-rate-performance NiS_(2)@OMGC anode material composed of monodispersed NiS_(2) nanocrystals(8.8±1.7 nm in size)and N,S-co-doped graphenic carbon(GC).The NiS_(2)@OMGC material has a three-dimensionally ordered macroporous(3DOM)morphology,and numerous NiS_(2) nanocrystals are uniformly embedded in GC,forming a core-shell structure in the local area.Ultrafine NiS_(2) nanocrystals and their nano-microstructure demonstrate high pseudocapacitive Na-storage capability and thus excellent rate performance(355.7 mAh/g at 20.0 A/g).A SIHC device fabricated using NiS_(2)@OMGC and commercial activated carbon(AC)cathode exhibits ultrahigh energy densities(197.4 Wh/kg at 398.8 W/kg)and power densities(43.9 kW/kg at 41.3 Wh/kg),together with a long life span.This outcome exemplifies the rational architecture and composition design of this type of anode material.This strategy can be extended to the design and synthesis of a wide range of high-performance electrode materials for energy storage applications.展开更多
Lithium-sulfur(Li-S)batteries are hampered by the infamous shuttle effect and slow redox kinetics,resulting in rapid capacity decay.Herein,a bifunctional catalysis CoB/BN@rGO with integrated structure and synergy effe...Lithium-sulfur(Li-S)batteries are hampered by the infamous shuttle effect and slow redox kinetics,resulting in rapid capacity decay.Herein,a bifunctional catalysis CoB/BN@rGO with integrated structure and synergy effect between adsorption and catalysis is proposed to solve the above problems.The integrated CoB and BN are simultaneously and uniformly introduced on the rGO substrate through a one-step calcination strategy,applied to modify the cathode side of PP separator.The transition metal borides can catalyze the conversion of lithium polysulfides(Li_(2)Sn,n≥4),whereas the bond of B-S is too weak to absorb LPS.Thus BN introduced can effectively restrict the diffusion of polysulfides via strong chemisorption with LiSnLi+…N,while the rGO substrate ensures smooth electron transfer for redox reaction.Therefore,through the integrated adsorption/catalysis,the shuttle effect is suppressed,the kinetics of redox reaction is enhanced,and the capacity decay is reduced.Using CoB/BN@rGO modified PP separator,the Li-S batteries with high initial capacity(1450 mAh g^(-1)at 0.35 mA cm^(-2))and long-cycle stability(700 cycles at 1.74 mA cm^(-2)with a decay rate of 0.032%per cycle)are achieved.This work provides a novel insight for the preparation of bifunctional catalysis with integrated structure for long-life Li-S batteries.展开更多
In recent years,the treatment of agricultural wastewater has been an important aspect of environmental protection.The purpose of photocatalytic technology is to degrade pollutants by utilizing solar light energy to st...In recent years,the treatment of agricultural wastewater has been an important aspect of environmental protection.The purpose of photocatalytic technology is to degrade pollutants by utilizing solar light energy to stimulate the migration of photocarriers to the surface of photocatalysts and occur reduction-oxidation reaction with pollutants in agricultural wastewater.Photocatalytic technology has the characteristics of high efficiency,sustainability,low-energy and free secondary pollution.It is an environmental and economical method to recover water quality that only needs sunlight.In this paper,the mechanism and research progress of photocatalytic removal of heavy metal ions and antibiotics from agricultural water pollution were reviewed by combining photocatalytic degradation process with agricultural treatment technology.The mechanism of influencing factors of photocatalytic degradation efficiency was discussed in detail and corresponding strategies were proposed,which has certain reference value for the development of photocatalytic degradation.展开更多
The inefficient separation of photogenerated carriers has become a serious problem that limits the photoelectrochemical(PEC)performance of semiconductors.Herein,a sol-gel method was used to prepare BiFeO_(3) ferroelec...The inefficient separation of photogenerated carriers has become a serious problem that limits the photoelectrochemical(PEC)performance of semiconductors.Herein,a sol-gel method was used to prepare BiFeO_(3) ferroelectric thin films with FTO and FTO/Au as substrates,respectively.The polarization electric field of the ferroelectric can more effectively separate the carriers generated in the photoelectrode.Meanwhile,the introduction of an Au buffer layer can reduce the resistance in the process of charge transfer,accelerate the carrier migration,and enhance the efficiency of the charge separation.Under light irradiation,Au/BiFeO_(3) photoelectrode exhibited an extraordinary improvement in PEC water splitting compared with BiFeO_(3).In addition,the ferroelectric polarization electric field causes band bending,which further accelerates the separation of electrons and holes and improves the PEC performance of the photoelectrode.This work promotes the effective application of ferroelectric films in PEC water splitting.展开更多
Lean electrolyte usage in lithium–sulfur battery(LSB)meets the demand of the high energy density.However,lean condition makes the electrolyte-related interface discrete,leading to retardation of ion transfer that dep...Lean electrolyte usage in lithium–sulfur battery(LSB)meets the demand of the high energy density.However,lean condition makes the electrolyte-related interface discrete,leading to retardation of ion transfer that depends on interfaces.Consequently,electrochemical reactions face restraint.Herein,lithium polyacrylate acid(LiPAA)with short-chain anions(molecular weight of 2000)is introduced into the cathode.Because of the polysulfide(PS)-philic instinct of the short-chain PAA anions,short-chain PS is captured inside of the cathode.In addition,LiPAA supplies Li^(+)to the short-chain PS captured.The strong interaction between Li_(2)S_(4)and LiPAA effectively decreases Li_(2)S_(4)migration to the anode during discharging.In a sense,the ion mass transfer pattern is thus changed comparing to traditional long-way mode between cathode and anode.Galvanostatic intermittent titration technique(GITT)proves that the interfacial reaction resistance is greatly decreased in the region where Li_(2)S_(x)(x≤4)reduction contributes most.In the same time,the reversibility of electrochemical reduction/oxidation is improved.Owing to the accelerated Li_(2)S_(x)(x≤4)reduction,Li implanting of only 0.3 wt.%plus O introduction up to 1.4 wt.%enables the LSB perform well even with 1/4 of regular electrolyte dosage(5μL mg^(-1))and high-sulfur loading(4.2 mg cm^(-2)),increasing its rate capacity C_(0.8/0.5)from 52.6%(without the LiPAA)to 92.3%(with the LiP AA)as well as a capacity of 518.7 mAh g^(-1)after 400 cycles at 0.8 mA cm^(-2).展开更多
Mechanistic understanding of the active intermediates of 2,6-diaminopyridine(DAP) dinitration in the concentrated nitric-sulfuric acid system is of crucial importance for the selectivity control of target product, i.e...Mechanistic understanding of the active intermediates of 2,6-diaminopyridine(DAP) dinitration in the concentrated nitric-sulfuric acid system is of crucial importance for the selectivity control of target product, i.e., 2,6-diamino-3,5-dinitropyridine(DADNP). The active intermediates determining the product selectivity are theoretically studied. The HSO_(4)^(-)-NO_(2)^(+) complex is proposed as the dominant active nitrating intermediate for the first time, which shows low energy barrier(i.e., 10.19 kcal·mol^(-1),1 kcal = 4.186 k J) for direct dinitration of DAP to DADNP. The formed water during the reaction results in not only the formation of less active SO_(4)^(2-)-NO_(2)^(+) complex, but also the occurance of DAP sulfonation(DAP-SO_(3)H intermediate)to facilitate the formation of mononitration byproduct. Meanwhile, the accompanied thermal effects cause the generation of undesirable pyridine-NHNO_(2) intermediate, which is difficult to be rearranged to yield DADNP, inhibiting the reaction and thus giving low DAP conversion. The insights reported here elucidates the importance of thermal effects elimination and water content control, confirmed experimentally in the batch-and micro-reaction systems.展开更多
Traditional thermal power units are continuously replaced by renewable energies,of which fluctuations and intermittence impose pressure on the frequency stability of the power system.Electrolytic aluminum load(EAL)acc...Traditional thermal power units are continuously replaced by renewable energies,of which fluctuations and intermittence impose pressure on the frequency stability of the power system.Electrolytic aluminum load(EAL)accounts for large amount of the local electric loads in some areas.The participation of EAL in local frequency control has huge application prospects.However,the controller design of EAL is difficult due to the measurement noise of the system frequency and the nonlinear dynamics of the EAL’s electric power consumption.Focusing on this problem,this paper proposes a control strategy for EAL to participate in the frequency control.For the controller design of the EAL system,the system frequency response model is established and the EAL transfer function model is developed based on the equivalent circuit of EAL.For the problem of load-side frequency measurement error,the frequency estimation method based on Kalman-filtering is designed.To improve the performance of EAL in the frequency control,a fuzzy EAL controller is designed.The testing examples show that the designed Kalman-filter has good performance in de-noising the measured frequency,and the designed fuzzy controller has better performance in stabilizing system frequency than traditional methods.展开更多
Recent developments in offshore renewable energy facilities,such as wind turbines and photovoltaic generators,often face challenges posed by the harsh offshore environments to which these structures are exposed.To ens...Recent developments in offshore renewable energy facilities,such as wind turbines and photovoltaic generators,often face challenges posed by the harsh offshore environments to which these structures are exposed.To ensure the continuous operation of these facilities,reliable numerical methods are urgently needed to capture the dynamics of ocean waves and their complex interactions with large-scale offshore structures.With the development of computational fluid dynamics techniques,advanced algorithms have been proposed to capture the complex fluid-structure interactions(FSI)in offshore applications.Although a variety of such algorithms have been introduced,a comprehensive review of all the latest developments in numerical modeling has not been available in the literature.To address this gap,this paper reviews recent numerical schemes and algorithms for dealing with FSI problems for offshore structures.The difficulties and challenges faced by recent algorithms are summarized,and future directions for advancing research into FSI in the offshore renewable energy field are also discussed.展开更多
Anaerobic ammonium oxidation(anammox)plays a critical role in nitrogen loss in estuarine and marine environments.However,the mechanisms underlying the formation and maintenance of the anammox bacterial community remai...Anaerobic ammonium oxidation(anammox)plays a critical role in nitrogen loss in estuarine and marine environments.However,the mechanisms underlying the formation and maintenance of the anammox bacterial community remain unclear.This study ana-lyzed the anammox bacterial diversity,community structure,and interspecific relationships in three estuaries along the Chinese coastline-the Changjiang Estuary(CJE),the Oujiang Estuary(OJE),and the Jiulong River Estuary(JLE)-as well as the South China Sea(SCS)to elucidate their community assembly mechanisms.The results indicated that the anammox bacterial commu-nity exhibited the highest ammonium concentration as well as the Shannon’s diversity index reflecting both species richness and evenness in the JLE.The lowest Shannon index was observed in the SCS.However,the anammox bacterial species richness was greatest in the CJE.Candidatus Scalindua was the predominant anammox bacteria identified in the coastal sediments,especially in the SCS sediments.Candidatus Brocadia and Candidatus Kuenenia were more abundant in the estuarine sediments,particularly in JLE,than in the SCS.Phylogenetic analysis revealed distinct differentiation among Candidatus Scalindua,Candidatus Broca-dia,and Candidatus Kuenenia,with the former exhibiting a greater level of diversity.There was significant spatial heterogeneity in the anammox bacteria across the four regions,characterized by distinct distribution patterns for rare species.Low-abundance(rare)bacteria thrived in their native habitats,whereas abundant taxa displayed greater dispersal capabilities.An analysis of the community assembly mechanism suggested that ecological drift predominantly shaped the overall anammox bacterial community in the coastal sediments.Rare species were more susceptible to dispersal limitations and environmental selection.Co-occurrence network analysis identified Candidatus Scalindua as a keystone genus and highlighted that rare species may play a crucial role in maintaining the ecological stability of the anammox bacterial community in coastal sediments.展开更多
Heteroatom doping is a universal approach to improve rate capability for various carbon anodes of sodium-ion batteries(SIBs)owing to the interlayer spacing expansion and pseudocapacitive enhancement.However,there is s...Heteroatom doping is a universal approach to improve rate capability for various carbon anodes of sodium-ion batteries(SIBs)owing to the interlayer spacing expansion and pseudocapacitive enhancement.However,there is still a limitation for ion adsorption of internal voids and dopants in the bulk phase of carbon materials due to the sluggish intercalation kinetics of large-size sodium ions.In this work,the highly sulfur-doped carbon nanosheets are synthesized and investigated as the anode of SIBs.It shows that the electrochemical performance in ether-based electrolytes significantly outperforms that in ester-based electrolytes.The carbon anodes exhibit a specific capacity of 617 mAh·g^(-1) at 100 mA·g^(-1) after 300 cycles,especially an outstanding rate performance of delivering specific capacities of 305 and 191 mAh·g^(-1) at current densities of 10 and 50 A·g^(-1),respectively.It is speculated that the ion-storage kinetics was greatly enhanced in ether-based electrolytes owing to the better accessibility of sodium-ion diffusion from electrode interfaces to internal hosts.As a result,the carbon nanovoids and sulfur dopants in the bulk phase are efficiently activated for ion storage.This work provides a new insight into the ion-storage mechanism optimization of carbon materials for SIBs.展开更多
Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene ...Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene was detected via MutMap and shown to encode potassium transporter OsHAK9.Phenotypic analysis of complementation and mutant lines demonstrated that OsHAK9 was an essential regulator responsible for seed germination under salt stress.OsHAK9 is highly expressed in germinating seed embryos.Ion contents and non-invasive micro-test technology results showed that OsHAK9 restricted K^(+)efflux in salt-exposed germinating seeds for the balance of K^(+)/Na^(+).Disruption of OsHAK9 significantly reduced gibberellin 4(GA4)levels,and the germination defective phenotype of oshak9a was partly rescued by exogenous GA_(3)treatment under salt stress.RNA sequencing(RNA-seq)and real-time quantitative polymerase chain reaction analysis demonstrated that the disruption of OsHAK9 improved the GA-deactivated gene OsGA2ox7 expression in germinating seeds under salt stress,and the expression of OsGA2ox7 was significantly inhibited by salt stress.Null mutants of OsGA2ox7 created using clustered,regularly interspaced,short palindromic repeat(CRISPR)/CRISPR-associated nuclease 9 approach displayed a dramatically increased seed germination ability under salt stress.Overall,our results highlight that OsHAK9 regulates seed germination performance under salt stress involving preventing GA degradation by mediating OsGA2ox7,which provides a novel clue about the relationship between GA and OsHAKs in rice.展开更多
We report a three-dimensional hierarchical ternary hybrid composite of molybdenum disulfide （MoS2）, reduced graphene oxide （GO）, and carbon nano- tubes （CNTs） prepared by a two-step process. Firstly, reduced GO-...We report a three-dimensional hierarchical ternary hybrid composite of molybdenum disulfide （MoS2）, reduced graphene oxide （GO）, and carbon nano- tubes （CNTs） prepared by a two-step process. Firstly, reduced GO-CNT composites with three-dimensional microstructuresare synthesized by hydrothermal treatment of an aqueous dispersion of GO and CNTs to form a composite structure via π-π interactions. Then, MoS2 nanoparticles are hydrothermally grown on the surfaces of the GO-CNT composite. This ternary composite shows superior electrocatalytic activity and stability in the hydrogen evolution reaction, with a low onset potential of only 35 mV, a Tafel slope of -38 mV.decade-1 and an apparent exchange current density of 74.25 mA.cm-2. The superior hydrogen evolution activity stemmed from the synergistic effect of MoS2 with its electrocatalytically active edge-sites and excellent electrical coupling to the underlying graphene and CNT network.展开更多
Organic-inorganic hybrid two-dimensional(2D)ruddlesden-popper(RP)perovskites with fantastic optoelectronic properties and good stability have attracted tremendous attention for the potential applications in photovolta...Organic-inorganic hybrid two-dimensional(2D)ruddlesden-popper(RP)perovskites with fantastic optoelectronic properties and good stability have attracted tremendous attention for the potential applications in photovoltaics and electroluminescence.Recently,a new allinorganic Cs2PbI2Cl22D perovskite has been proposed with excellent excitonic absorption and improved ambient and thermal stability.Herein,an interesting light-induced phase transition and photochromism in the Cs2PbI2Cl2were reported.Under low fluence light pumping,the room temperature photoluminescence(PL)of Cs2PbI2Cl2is dominated by a weak violet excitonic emission peaked at 412 nm.Surprisingly,the emission color gradually changes from violet to bright red while increasing the laser pumping fluence.This photochromic effect is determined to be caused by forming CsPbI3phase within the Cs2PbI2Cl2crystals,which is efficiently driven by thermal energy.Due to protection by the Cs2PbI2Cl2matrix,the embedded CsPbI3nanocrystals show improved stability than standard pure CsPbI3.Therefore,the Cs2PbI2Cl2perovskite with photochromic feature may find applications in optical encryption,as preliminarily shown in this work.展开更多
Purpose In order to improve the charged particle identi-fication capability,end-cap time-of-flight(ETOF)detector of the Beijing Spectrometer(BESIII)has been upgraded with multi-gap resistive plate chamber(MRPC)technol...Purpose In order to improve the charged particle identi-fication capability,end-cap time-of-flight(ETOF)detector of the Beijing Spectrometer(BESIII)has been upgraded with multi-gap resistive plate chamber(MRPC)technology,aiming at an overall time resolution of 80 ps for minimum-ionization particles to extend the K/πseparation(2σ)momentum range to 1.4 GeV/c.Methods The previous version of ETOF in BESIII consisted of plastic scintillators.The multi-hit events distort both shape and amplitude of the output signals.MRPC technique was chosen for the BESIII ETOF upgrade as it provides high time resolution and high detection efficiency,is of relatively low cost and is insensitive to neutral particles.Most importantly,the fine segmentation of the MRPC readout stripes can suppress multi-hit events effectively.Results The final design of MRPC module for ETOF is characterized by double-stack(2×6)structure,dual-end readout mode and precision electronics.To batch-produce and test these MRPC modules,a series of tools and production procedures as well as related performance simulation and test methods were developed.Results showed that each MRPC module’s intrinsic time resolution(including the electronics contribution)is around 50 ps and the efficiency is better than 97%.The overall performance of the upgraded ETOF is better than the designed index.The new ETOF has been successfully installed at BESIII and run in 2016.展开更多
基金supported by the National Natural Science Foundation of China(22078228)。
文摘Zwitterions(ZIs)are considered as an ideal,novel ionic conductive medium due to their high dipole moment and good solubility of lithium salts.However,the strong interactions between ZIs and Li^(+)severely hinder Li^(+)migration.Herein,a quasi-solid electrolyte(MSQSE-2Na)was fabricated by adding sodium bis(fluorosulfonyl)imide(NaFSI)to sulfobetaine methacrylate(SBMA,a ZI)based polymerization system.Na^(+)occupies the–SO_(3)^(-)site in SBMA prior to Li^(+),which weakens the self-crosslinking of SBMA and frees the Li^(+)bound to the polymer segments.Thus,the polymer conformation of MSQSE-2Na changes to a relaxed,homogeneous"sea-island"type.Meanwhile,Na^(+),due to its electron-withdrawing effect,decreases the electron cloud density of the polymer segments,building a weakly coordinated environment in MSQSE-2Na.Consequently,MSQSE-2Na exhibits excellent ionic conductivity of 7.38×10^(-4)S cm^(-1)and a high Li^(+)transference number of 0.632 at 25℃.The(-)Li|MSQSE-2Na|Li(+)cells exhibit super stability,sustaining operation for over 6182h.The(-)Li|MSQSE-2Na|LiFePO_(4)(+)cells demonstrate outstanding charge/discharge reversibility with a Coulombic efficiency exceeding 99.9%over 270 cycles(≈4500 h),with a capacity retention of 70.0%.This work proposes a new design concept for regulating the polymer conformation and charge characteristics through competitive coordination,thereby advancing the application of ZI-based polymer electrolytes in lithium metal batteries.
基金supported by National Natural Science Foundation of China(No.22078228).
文摘The sluggish bidirectional conversion rate between Li_(2)S_(n)(2≤n≤4)and Li_(2)S,coupled with the uncontrolled deposition of Li_(2)S,significantly impedes the realization of high-performance lithium-sulfur batteries(LSBs).In this study,a metal-organic framework was employed as a precursor for the synthesis of a CoO_(x)-CeO_(2-y)/C(0<x<3/2,0<y<1/2)heterojunction via pyrolysis,which was subsequently introduced onto the cathode side of the polypropylene(PP)separator in LSBs.The modification of CoO_(x)-CeO_(2-y)/C enhances the kinetics of converting of Li_(2)S_(n)to Li_(2)S during the discharge process.The Tafel slope for the Li_(2)S deposition reaction is reduced to 52.1 mV/dec,representing a 56.6%decrease compared to LSBs with bare PP separator.Conversely,during the charging process,the modification lowers the energy barrier for the Li_(2)S decomposition reaction,with the activation energy reduced to 6.12 kJ/mol,indicating a 70.3%decrease relative to LSBs with PP separator only.Consequently,more Li_(2)S is promoted to undergo decomposition.The CoO_(x)-CeO_(2-y)/C heterojunction facilitates uniform deposition of Li_(2)S,featuringfine particles and a uniform distribution,after brief potentiostatic charging for decomposition,thereby effectively mitigating the deactivation of sulfur species.Thanks to the enhanced bidirectional conversion of lithium polysulfides(LiPS)facilitated by the CoO_(x)-CeO_(2-y)/C modification layer,the(-)Li|CoO_(x)-CeO_(2-y)/C@PPIS(+)coin cell maintains a Coulombic efficiency of 90.4%after 500 cycles at a current density of 1 C,exhibiting a low capacity-decay rate of only 0.081%per cycle,thereby demonstrating excellent long-cycle stability.
基金National Natural Science Foundation of China (22078228)。
文摘Solid-state polymer electrolytes(SPEs) capable of withstanding high voltage are considered to be key for next-generation energy storage devices with inherent safety as well as high energy density.This study involves the rational design of solid-state-C≡N functionalized P(VEC_1-CEA_(0.3))/LiTFSI@CE SPEs and its synthesis by in-situ free radical polymerization of vinyl ethylene carbonate(VEC) and 2-cyanoethyl acrylate(CEA).In situ polymerization yields electrode/electrolyte interfaces with low interfacial resistance,forming a stable SEI layer enriched with LiF,Li_(3)N,and RCOOLi,ensuring stable Li plating/stripping for over 1400 h.The-C≡N moiety renders the αH on the adjacent αC positively charged,thereby endowing it with the capability to anchor TFSI^(-).Simultaneously,the incorporation of-C≡N moiety diminishes the electron-donating ability of the C=O,C-O-C,and-C≡N functional groups,facilitating not only the ion conductivity enhancement but also a more rapid Li^(+)migration proved by DFT theoretical calculations and Raman spectroscopy.At room temperature,t_(Li+) of 0.60 for P(VEC_1-CEA_(0.3))/LiTFSI@CE SPEs is achieved when the ionic conductivity σ_(Li+)is 2.63×10^(-4) S cm^(-1) and the electrochemical window is expanded to5.0 V.Both coin cells with high-areal-loading cathodes and the 6.5-mAh pouch cell,exhibit stable charge/discharge cycling.At 25℃,the 4.45-V Li|P(VEC_1-CEA_(0.3))/LiTFSI@CE|LiCoO_(2) battery performs stable cycling over 200 cycles at 0.2 C,with a capacity retention of 82.1%.
基金supported by the National Natural Science Foundation of Tianjin(No.20JCQNJC01280)the National Natural Science Foundation of China(No.21905201)+1 种基金the support of the scientifi c research project from China Three Gorges Corporation(No.202103406)supported by Tohoku University and JSPS KAKENHI(No.JP16J06828).
文摘Sodium-ion hybrid capacitor(SIHC)is one of the most promising alternatives for large-scale energy storage due to its high energy and power densities,natural abundance,and low cost.However,overcoming the imbalance between slow Na^(+)reaction kinetics of battery-type anodes and rapid ion adsorption/desorption of capacitive cathodes is a significant challenge.Here,we propose the high-rate-performance NiS_(2)@OMGC anode material composed of monodispersed NiS_(2) nanocrystals(8.8±1.7 nm in size)and N,S-co-doped graphenic carbon(GC).The NiS_(2)@OMGC material has a three-dimensionally ordered macroporous(3DOM)morphology,and numerous NiS_(2) nanocrystals are uniformly embedded in GC,forming a core-shell structure in the local area.Ultrafine NiS_(2) nanocrystals and their nano-microstructure demonstrate high pseudocapacitive Na-storage capability and thus excellent rate performance(355.7 mAh/g at 20.0 A/g).A SIHC device fabricated using NiS_(2)@OMGC and commercial activated carbon(AC)cathode exhibits ultrahigh energy densities(197.4 Wh/kg at 398.8 W/kg)and power densities(43.9 kW/kg at 41.3 Wh/kg),together with a long life span.This outcome exemplifies the rational architecture and composition design of this type of anode material.This strategy can be extended to the design and synthesis of a wide range of high-performance electrode materials for energy storage applications.
基金supported by the National Natural Science Foundation of China(22078228)。
文摘Lithium-sulfur(Li-S)batteries are hampered by the infamous shuttle effect and slow redox kinetics,resulting in rapid capacity decay.Herein,a bifunctional catalysis CoB/BN@rGO with integrated structure and synergy effect between adsorption and catalysis is proposed to solve the above problems.The integrated CoB and BN are simultaneously and uniformly introduced on the rGO substrate through a one-step calcination strategy,applied to modify the cathode side of PP separator.The transition metal borides can catalyze the conversion of lithium polysulfides(Li_(2)Sn,n≥4),whereas the bond of B-S is too weak to absorb LPS.Thus BN introduced can effectively restrict the diffusion of polysulfides via strong chemisorption with LiSnLi+…N,while the rGO substrate ensures smooth electron transfer for redox reaction.Therefore,through the integrated adsorption/catalysis,the shuttle effect is suppressed,the kinetics of redox reaction is enhanced,and the capacity decay is reduced.Using CoB/BN@rGO modified PP separator,the Li-S batteries with high initial capacity(1450 mAh g^(-1)at 0.35 mA cm^(-2))and long-cycle stability(700 cycles at 1.74 mA cm^(-2)with a decay rate of 0.032%per cycle)are achieved.This work provides a novel insight for the preparation of bifunctional catalysis with integrated structure for long-life Li-S batteries.
基金supported by the National Natural Science Foundation of China(52272213)Natural Science Research of Jiangsu Higher Education Institutions of China(21KJB140005)Jiangsu Province and Education Ministry Co-Sponsored Synergistic Innovation Center of Modern Agricultural Equipment(XTCX2024).
文摘In recent years,the treatment of agricultural wastewater has been an important aspect of environmental protection.The purpose of photocatalytic technology is to degrade pollutants by utilizing solar light energy to stimulate the migration of photocarriers to the surface of photocatalysts and occur reduction-oxidation reaction with pollutants in agricultural wastewater.Photocatalytic technology has the characteristics of high efficiency,sustainability,low-energy and free secondary pollution.It is an environmental and economical method to recover water quality that only needs sunlight.In this paper,the mechanism and research progress of photocatalytic removal of heavy metal ions and antibiotics from agricultural water pollution were reviewed by combining photocatalytic degradation process with agricultural treatment technology.The mechanism of influencing factors of photocatalytic degradation efficiency was discussed in detail and corresponding strategies were proposed,which has certain reference value for the development of photocatalytic degradation.
基金This work was supported by National Natural Science Foundation of China(Grant No.51702130)the Innovation/Entrepreneurship Program of Jiangsu Province and the project of Zhenjiang Key Laboratory of Advanced Sensing Materials and Devices(No.SS2018001)。
文摘The inefficient separation of photogenerated carriers has become a serious problem that limits the photoelectrochemical(PEC)performance of semiconductors.Herein,a sol-gel method was used to prepare BiFeO_(3) ferroelectric thin films with FTO and FTO/Au as substrates,respectively.The polarization electric field of the ferroelectric can more effectively separate the carriers generated in the photoelectrode.Meanwhile,the introduction of an Au buffer layer can reduce the resistance in the process of charge transfer,accelerate the carrier migration,and enhance the efficiency of the charge separation.Under light irradiation,Au/BiFeO_(3) photoelectrode exhibited an extraordinary improvement in PEC water splitting compared with BiFeO_(3).In addition,the ferroelectric polarization electric field causes band bending,which further accelerates the separation of electrons and holes and improves the PEC performance of the photoelectrode.This work promotes the effective application of ferroelectric films in PEC water splitting.
基金supported by National Nature Science Foundation of China(NSFC22078228)。
文摘Lean electrolyte usage in lithium–sulfur battery(LSB)meets the demand of the high energy density.However,lean condition makes the electrolyte-related interface discrete,leading to retardation of ion transfer that depends on interfaces.Consequently,electrochemical reactions face restraint.Herein,lithium polyacrylate acid(LiPAA)with short-chain anions(molecular weight of 2000)is introduced into the cathode.Because of the polysulfide(PS)-philic instinct of the short-chain PAA anions,short-chain PS is captured inside of the cathode.In addition,LiPAA supplies Li^(+)to the short-chain PS captured.The strong interaction between Li_(2)S_(4)and LiPAA effectively decreases Li_(2)S_(4)migration to the anode during discharging.In a sense,the ion mass transfer pattern is thus changed comparing to traditional long-way mode between cathode and anode.Galvanostatic intermittent titration technique(GITT)proves that the interfacial reaction resistance is greatly decreased in the region where Li_(2)S_(x)(x≤4)reduction contributes most.In the same time,the reversibility of electrochemical reduction/oxidation is improved.Owing to the accelerated Li_(2)S_(x)(x≤4)reduction,Li implanting of only 0.3 wt.%plus O introduction up to 1.4 wt.%enables the LSB perform well even with 1/4 of regular electrolyte dosage(5μL mg^(-1))and high-sulfur loading(4.2 mg cm^(-2)),increasing its rate capacity C_(0.8/0.5)from 52.6%(without the LiPAA)to 92.3%(with the LiP AA)as well as a capacity of 518.7 mAh g^(-1)after 400 cycles at 0.8 mA cm^(-2).
基金financially supported by the National Natural Science Foundation of China, China (21922803, 22122807, and 22008072)the Innovation Program of Shanghai Municipal Education Commission, China+1 种基金the Program of Shanghai Academic/Technology Research Leader, China (21XD1421000)the China Postdoctoral Science Foundation, China (2020M671025 and 2019TQ0093)。
文摘Mechanistic understanding of the active intermediates of 2,6-diaminopyridine(DAP) dinitration in the concentrated nitric-sulfuric acid system is of crucial importance for the selectivity control of target product, i.e., 2,6-diamino-3,5-dinitropyridine(DADNP). The active intermediates determining the product selectivity are theoretically studied. The HSO_(4)^(-)-NO_(2)^(+) complex is proposed as the dominant active nitrating intermediate for the first time, which shows low energy barrier(i.e., 10.19 kcal·mol^(-1),1 kcal = 4.186 k J) for direct dinitration of DAP to DADNP. The formed water during the reaction results in not only the formation of less active SO_(4)^(2-)-NO_(2)^(+) complex, but also the occurance of DAP sulfonation(DAP-SO_(3)H intermediate)to facilitate the formation of mononitration byproduct. Meanwhile, the accompanied thermal effects cause the generation of undesirable pyridine-NHNO_(2) intermediate, which is difficult to be rearranged to yield DADNP, inhibiting the reaction and thus giving low DAP conversion. The insights reported here elucidates the importance of thermal effects elimination and water content control, confirmed experimentally in the batch-and micro-reaction systems.
基金funded by Science and Technology Project of State Grid Corporation of China:Research on the Construction and Evaluation Technology of the Data-Driven-based Adjustable Resource Pool of Typical Industrial Enterprises,Grant No.1400-202016386A-0-0-00.
文摘Traditional thermal power units are continuously replaced by renewable energies,of which fluctuations and intermittence impose pressure on the frequency stability of the power system.Electrolytic aluminum load(EAL)accounts for large amount of the local electric loads in some areas.The participation of EAL in local frequency control has huge application prospects.However,the controller design of EAL is difficult due to the measurement noise of the system frequency and the nonlinear dynamics of the EAL’s electric power consumption.Focusing on this problem,this paper proposes a control strategy for EAL to participate in the frequency control.For the controller design of the EAL system,the system frequency response model is established and the EAL transfer function model is developed based on the equivalent circuit of EAL.For the problem of load-side frequency measurement error,the frequency estimation method based on Kalman-filtering is designed.To improve the performance of EAL in the frequency control,a fuzzy EAL controller is designed.The testing examples show that the designed Kalman-filter has good performance in de-noising the measured frequency,and the designed fuzzy controller has better performance in stabilizing system frequency than traditional methods.
基金funded by China Longyuan Power Group Corporation Limited(Grant No.LYX-2023-07).
文摘Recent developments in offshore renewable energy facilities,such as wind turbines and photovoltaic generators,often face challenges posed by the harsh offshore environments to which these structures are exposed.To ensure the continuous operation of these facilities,reliable numerical methods are urgently needed to capture the dynamics of ocean waves and their complex interactions with large-scale offshore structures.With the development of computational fluid dynamics techniques,advanced algorithms have been proposed to capture the complex fluid-structure interactions(FSI)in offshore applications.Although a variety of such algorithms have been introduced,a comprehensive review of all the latest developments in numerical modeling has not been available in the literature.To address this gap,this paper reviews recent numerical schemes and algorithms for dealing with FSI problems for offshore structures.The difficulties and challenges faced by recent algorithms are summarized,and future directions for advancing research into FSI in the offshore renewable energy field are also discussed.
基金supported by grants from the National Natural Science Foundation of China(42125603,42430404,and 42421004)the National Key Research and Development Program of China(2023YFF0805002).
文摘Anaerobic ammonium oxidation(anammox)plays a critical role in nitrogen loss in estuarine and marine environments.However,the mechanisms underlying the formation and maintenance of the anammox bacterial community remain unclear.This study ana-lyzed the anammox bacterial diversity,community structure,and interspecific relationships in three estuaries along the Chinese coastline-the Changjiang Estuary(CJE),the Oujiang Estuary(OJE),and the Jiulong River Estuary(JLE)-as well as the South China Sea(SCS)to elucidate their community assembly mechanisms.The results indicated that the anammox bacterial commu-nity exhibited the highest ammonium concentration as well as the Shannon’s diversity index reflecting both species richness and evenness in the JLE.The lowest Shannon index was observed in the SCS.However,the anammox bacterial species richness was greatest in the CJE.Candidatus Scalindua was the predominant anammox bacteria identified in the coastal sediments,especially in the SCS sediments.Candidatus Brocadia and Candidatus Kuenenia were more abundant in the estuarine sediments,particularly in JLE,than in the SCS.Phylogenetic analysis revealed distinct differentiation among Candidatus Scalindua,Candidatus Broca-dia,and Candidatus Kuenenia,with the former exhibiting a greater level of diversity.There was significant spatial heterogeneity in the anammox bacteria across the four regions,characterized by distinct distribution patterns for rare species.Low-abundance(rare)bacteria thrived in their native habitats,whereas abundant taxa displayed greater dispersal capabilities.An analysis of the community assembly mechanism suggested that ecological drift predominantly shaped the overall anammox bacterial community in the coastal sediments.Rare species were more susceptible to dispersal limitations and environmental selection.Co-occurrence network analysis identified Candidatus Scalindua as a keystone genus and highlighted that rare species may play a crucial role in maintaining the ecological stability of the anammox bacterial community in coastal sediments.
基金supported by the National Natural Science Foundation of China(Nos.52307243 and 52272213)the Natural Science Foundation of Jiangsu Province(No.BK20230537)+2 种基金the China Postdoctoral Science Foundation(No.2023M741451)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.23KJB140003)the Jiangsu University Advanced Talent Research Startup Fund(No.22JDG052).
文摘Heteroatom doping is a universal approach to improve rate capability for various carbon anodes of sodium-ion batteries(SIBs)owing to the interlayer spacing expansion and pseudocapacitive enhancement.However,there is still a limitation for ion adsorption of internal voids and dopants in the bulk phase of carbon materials due to the sluggish intercalation kinetics of large-size sodium ions.In this work,the highly sulfur-doped carbon nanosheets are synthesized and investigated as the anode of SIBs.It shows that the electrochemical performance in ether-based electrolytes significantly outperforms that in ester-based electrolytes.The carbon anodes exhibit a specific capacity of 617 mAh·g^(-1) at 100 mA·g^(-1) after 300 cycles,especially an outstanding rate performance of delivering specific capacities of 305 and 191 mAh·g^(-1) at current densities of 10 and 50 A·g^(-1),respectively.It is speculated that the ion-storage kinetics was greatly enhanced in ether-based electrolytes owing to the better accessibility of sodium-ion diffusion from electrode interfaces to internal hosts.As a result,the carbon nanovoids and sulfur dopants in the bulk phase are efficiently activated for ion storage.This work provides a new insight into the ion-storage mechanism optimization of carbon materials for SIBs.
基金supported by the National Natural Science Foundation of China(Grant Nos.32272169,32000377,32172037,and 31601387)the Natural Science Foundation of Guangdong Province(Grant No.2022A1515110449)the Hainan Yazhou Bay Seed Laboratory(project of B21HJ1002)。
文摘Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene was detected via MutMap and shown to encode potassium transporter OsHAK9.Phenotypic analysis of complementation and mutant lines demonstrated that OsHAK9 was an essential regulator responsible for seed germination under salt stress.OsHAK9 is highly expressed in germinating seed embryos.Ion contents and non-invasive micro-test technology results showed that OsHAK9 restricted K^(+)efflux in salt-exposed germinating seeds for the balance of K^(+)/Na^(+).Disruption of OsHAK9 significantly reduced gibberellin 4(GA4)levels,and the germination defective phenotype of oshak9a was partly rescued by exogenous GA_(3)treatment under salt stress.RNA sequencing(RNA-seq)and real-time quantitative polymerase chain reaction analysis demonstrated that the disruption of OsHAK9 improved the GA-deactivated gene OsGA2ox7 expression in germinating seeds under salt stress,and the expression of OsGA2ox7 was significantly inhibited by salt stress.Null mutants of OsGA2ox7 created using clustered,regularly interspaced,short palindromic repeat(CRISPR)/CRISPR-associated nuclease 9 approach displayed a dramatically increased seed germination ability under salt stress.Overall,our results highlight that OsHAK9 regulates seed germination performance under salt stress involving preventing GA degradation by mediating OsGA2ox7,which provides a novel clue about the relationship between GA and OsHAKs in rice.
基金Majid Khan and Ammar Bin Yousaf contributed equally to this work. This work is supported by the China Scholarship Council （CSC）, and the National Natural Science Foundation of China （Nos. 11275203 and U1232128）.
文摘We report a three-dimensional hierarchical ternary hybrid composite of molybdenum disulfide （MoS2）, reduced graphene oxide （GO）, and carbon nano- tubes （CNTs） prepared by a two-step process. Firstly, reduced GO-CNT composites with three-dimensional microstructuresare synthesized by hydrothermal treatment of an aqueous dispersion of GO and CNTs to form a composite structure via π-π interactions. Then, MoS2 nanoparticles are hydrothermally grown on the surfaces of the GO-CNT composite. This ternary composite shows superior electrocatalytic activity and stability in the hydrogen evolution reaction, with a low onset potential of only 35 mV, a Tafel slope of -38 mV.decade-1 and an apparent exchange current density of 74.25 mA.cm-2. The superior hydrogen evolution activity stemmed from the synergistic effect of MoS2 with its electrocatalytically active edge-sites and excellent electrical coupling to the underlying graphene and CNT network.
基金supported by the Macao Science and Technology Development Fund(FDCT-116/2016/A3,FDCT-091/2017/A2,FDCT-014/2017/AMJ and FDCT-199/2017/A3)Start-up Research Grant Fund from University of Macao(SRG2016-00002-FST)+3 种基金Research and Development Grant for Chair Professor Fund from University of Macao(CPG2018-00026-FST)Research Grant(SRG201600087-FST,MYRG2018-00148-IAPME and MYRG2018-00142-IAPME)from University of Macaothe National Natural Science Foundation of China(91733302,61935017 and 61605073)the Natural Science Foundation of Guangdong Province of China(2019A1515012186)。
文摘Organic-inorganic hybrid two-dimensional(2D)ruddlesden-popper(RP)perovskites with fantastic optoelectronic properties and good stability have attracted tremendous attention for the potential applications in photovoltaics and electroluminescence.Recently,a new allinorganic Cs2PbI2Cl22D perovskite has been proposed with excellent excitonic absorption and improved ambient and thermal stability.Herein,an interesting light-induced phase transition and photochromism in the Cs2PbI2Cl2were reported.Under low fluence light pumping,the room temperature photoluminescence(PL)of Cs2PbI2Cl2is dominated by a weak violet excitonic emission peaked at 412 nm.Surprisingly,the emission color gradually changes from violet to bright red while increasing the laser pumping fluence.This photochromic effect is determined to be caused by forming CsPbI3phase within the Cs2PbI2Cl2crystals,which is efficiently driven by thermal energy.Due to protection by the Cs2PbI2Cl2matrix,the embedded CsPbI3nanocrystals show improved stability than standard pure CsPbI3.Therefore,the Cs2PbI2Cl2perovskite with photochromic feature may find applications in optical encryption,as preliminarily shown in this work.
基金supported by the National Natural Science Foundation of China(Nos.10979003,11675172,U1232206)Chinese Academy of Sciences(No.1G201331231172010).
文摘Purpose In order to improve the charged particle identi-fication capability,end-cap time-of-flight(ETOF)detector of the Beijing Spectrometer(BESIII)has been upgraded with multi-gap resistive plate chamber(MRPC)technology,aiming at an overall time resolution of 80 ps for minimum-ionization particles to extend the K/πseparation(2σ)momentum range to 1.4 GeV/c.Methods The previous version of ETOF in BESIII consisted of plastic scintillators.The multi-hit events distort both shape and amplitude of the output signals.MRPC technique was chosen for the BESIII ETOF upgrade as it provides high time resolution and high detection efficiency,is of relatively low cost and is insensitive to neutral particles.Most importantly,the fine segmentation of the MRPC readout stripes can suppress multi-hit events effectively.Results The final design of MRPC module for ETOF is characterized by double-stack(2×6)structure,dual-end readout mode and precision electronics.To batch-produce and test these MRPC modules,a series of tools and production procedures as well as related performance simulation and test methods were developed.Results showed that each MRPC module’s intrinsic time resolution(including the electronics contribution)is around 50 ps and the efficiency is better than 97%.The overall performance of the upgraded ETOF is better than the designed index.The new ETOF has been successfully installed at BESIII and run in 2016.
