Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium batteries.However,atomic insights into the EDL structures on heteroatom-modified graphite ano...Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium batteries.However,atomic insights into the EDL structures on heteroatom-modified graphite anodes and EDL evolution with electrode potential are very lacking.Herein,a constant-potential molecular dynamics(CPMD)method is proposed to probe the EDL structure under working conditions,taking N-doped graphite electrodes and carbonate electrolytes as an example.An interface model was developed,incorporating the electrode potential and atom electronegativities.As a result,an insightful atomic scenario for the EDL structure under varied electrode potentials has been established,which unveils the important role of doping sites in regulating both the EDL structures and the following electrochemical reactions at the atomic level.Specifically,the negatively charged N atoms repel the anions and adsorb Li~+at high and low potentials,respectively.Such preferential adsorption suggests that Ndoped graphite can promote Li~+desolvation and regulate the location of Li~+deposition.This CPMD method not only unveils the mysterious function of N-doping from the viewpoint of EDL at the atomic level but also applies to probe the interfacial structure on other complicated electrodes.展开更多
Kobuvirus comprises 6 officially recognized species,namely Aichivirus A-F,and can be further divided into 20 genotypes through VP1 gene phylogenetic analysis(https://ictv.global/report/chapter/picornaviridae/picornavi...Kobuvirus comprises 6 officially recognized species,namely Aichivirus A-F,and can be further divided into 20 genotypes through VP1 gene phylogenetic analysis(https://ictv.global/report/chapter/picornaviridae/picornaviridae/kobuvirus).Aichivirus A in human,Aichivirus B in bovine,Aichivirus C in porcine and caprine,Aichivirus D in yak have been proved to be associated with diarrhea(Chen Y S et al.2013;Yang et al.2015;Zhu et al.2016;Zhai et al.2017;Wang et al.2020;Abi et al.2022;Yan et al.2023).展开更多
Lithium metal anode(LMA) is a promising candidate for achieving next-generation high-energy-density batteries due to its ultrahigh theoretical capacity and most negative electrochemical potential. However, the practic...Lithium metal anode(LMA) is a promising candidate for achieving next-generation high-energy-density batteries due to its ultrahigh theoretical capacity and most negative electrochemical potential. However, the practical application of lithium metal battery(LMB) is largely retarded by the instable interfaces, uncontrolled dendrites, and rapid capacity deterioration. Herein, we present a comprehensive overview towards the working principles and inherent challenges of LMAs. Firstly, we diligently summarize the intrinsic mechanism of Li stripping and plating process. The recent advances in atomic and mesoscale simulations which are crucial in guiding mechanism study and material design are also summarized. Furthermore, the advanced engineering strategies which have been proved effective in protecting LMAs are systematically reviewed, including electrolyte optimization, artificial interface, composite/alloy anodes and so on. Finally, we highlight the current limitations and promising research directions of LMAs. This review sheds new lights on deeply understanding the intrinsic mechanism of LMAs, and calls for more endeavors to realize practical Li metal batteries.展开更多
The advance of microelectronics requires the micropower of microsupercapacitors(MSCs) to possess wide temperature-and damage-tolerance beyond high areal energy density.The properties of electrolyte are crucial for MSC...The advance of microelectronics requires the micropower of microsupercapacitors(MSCs) to possess wide temperature-and damage-tolerance beyond high areal energy density.The properties of electrolyte are crucial for MSCs to meet the above requirements.Here,an organohydrogel electrolyte,featured with high salt tolerance,ultralow freezing point,and strong self-healing ability,is experimentally realized via modulating its inner dynamic bonds.Spectroscopic and theoretical analysis reveal that dimethyl sulfoxide has the ability to reconstruct Li^(+)solvation structure,and interact with free water and polyvinyl alcohol chains via forming hydrogen bonds.The organohydrogel electrolyte is employed to build MSCs,which show a boosted energy density,promising wide temperature range-and damage-tolerant ability.These attractive features make the designed organohydrogel electrolyte have great potential to advance MSCs.展开更多
Lithium-sulfur(Li-S)batteries have attracted wide attention for their high theoretical energy density,low cost,and environmental friendliness.However,the shuttle effect of polysulfides and the insulation of active mat...Lithium-sulfur(Li-S)batteries have attracted wide attention for their high theoretical energy density,low cost,and environmental friendliness.However,the shuttle effect of polysulfides and the insulation of active materials severely restrict the development of Li-S batteries.Constructing conductive sulfur scaffolds with catalytic conversion capability for cathodes is an efficient approach to solving above issues.Vanadium-based compounds and their heterostructures have recently emerged as functional sulfur catalysts supported on conductive scaffolds.These compounds interact with polysulfides via different mechanisms to alleviate the shuttle effect and accelerate the redox kinetics,leading to higher Coulombic efficiency and enhanced sulfur utilization.Reports on vanadium-based nanomaterials in Li-S batteries have been steadily increasing over the past several years.In this review,first,we provide an overview of the synthesis of vanadium-based compounds and heterostructures.Then,we discuss the interactions and constitutive relationships between vanadium-based catalysts and polysulfides formed at sulfur cathodes.We summarize the mechanisms that contribute to the enhancement of electrochemical performance for various types of vanadium-based catalysts,thus providing insights for the rational design of sulfur catalysts.Finally,we offer a perspective on the future directions for the research and development of vanadium-based sulfur catalysts.展开更多
N-doped porous carbon has been extensively investigated for broad electrochemical applications.The performance is significantly impacted by the electrochemical double layer(EDL),which is material dependent and hard to...N-doped porous carbon has been extensively investigated for broad electrochemical applications.The performance is significantly impacted by the electrochemical double layer(EDL),which is material dependent and hard to characterize.Limited understanding of doping-derived EDL structure hinders insight into the structure-performance relations and the rational design of high-performance materials.Thus,we analyzed the mass and chemical composition variation of EDL within electrochemical operation by electrochemical quartz crystal microbalance,in-situ X-ray photoelectron spectroscopy,and time-offlight secondary ion mass spectrometry.We found that N-doping triggers specifically adsorbed propylene carbonate solvent in the inner Helmholtz plane(IHP),which prevents ion rearrangement and enhances the migration of cations.However,this specific adsorption accelerated solvent decomposition,rendering rapid performance degradation in practical devices.This work reveals that the surface chemistry of electrodes can cause specific adsorption of solvents and change the EDL structure,which complements the classical EDL theory and provide guidance for practical applications.展开更多
1.Introduction Achieving carbon neutrality and sustainable development demands an extensive and profound systemic reform of China’s energy,industry,and economy structures.According to statistics[1,2],almost 90%of CO_...1.Introduction Achieving carbon neutrality and sustainable development demands an extensive and profound systemic reform of China’s energy,industry,and economy structures.According to statistics[1,2],almost 90%of CO_(2) emissions in China come from the energy sector,with the leading emission sources being power(48%),industry(36%),transport(8%),and buildings(5%)[1].展开更多
The Cu_(65)Ni_(35) alloy liquid was undercooled by the fluxing method,and the rapid solidification structure was obtained by natural cooling.The solidification interface migration information of Cu_(65)Ni_(35) alloy l...The Cu_(65)Ni_(35) alloy liquid was undercooled by the fluxing method,and the rapid solidification structure was obtained by natural cooling.The solidification interface migration information of Cu_(65)Ni_(35) alloy liquid in rapid solidification stage was photographed with the help of high-speed camera,and the recalescence velocity was calculated.The microstructure evolution of the alloy was systematically studied by observing the microstructure morphology and taking photos on the metallographic microscope.By analyzing the evolution of dendrite grain size and microstructure microhardness with undercoolingand relying on electron backscatter diffraction(EBSD)technology,the grain refinement mechanism of microstructure under high undercooling and low undercooling is finally confirmed.展开更多
Nanocarbons are of progressively increasing importance in energy electrocatalysis, including oxygen reduction, oxygen evolution, hydrogen evolution, COreduction, etc. Precious-metal-free or metal-free nanocarbon-based...Nanocarbons are of progressively increasing importance in energy electrocatalysis, including oxygen reduction, oxygen evolution, hydrogen evolution, COreduction, etc. Precious-metal-free or metal-free nanocarbon-based electrocatalysts have been revealed to potentially have effective activity and remarkable durability, which is promising to replace precious metals in some important energy technologies,such as fuel cells, metal–air batteries, and water splitting. In this review, rather than overviewing recent progress completely, we aim to give an in-depth digestion of present achievements, focusing on the different roles of nanocarbons and material design principles. The multifunctionalities of nanocarbon substrates(accelerating the electron and mass transport, regulating the incorporation of active components,manipulating electron structures, generating confinement effects, assembly into 3 D free-standing electrodes) and the intrinsic activity of nanocarbon catalysts(multi-heteroatom doping, hierarchical structure,topological defects) are discussed systematically, with perspectives on the further research in this rising research field. This review is inspiring for more insights and methodical research in mechanism understanding, material design, and device optimization, leading to a targeted and high-efficiency development of energy electrocatalysis.展开更多
Chicken embryo fibroblasts (CEFs) are among the most commonly used cells for the study of interactions between chicken hosts and H5N1 avian influenza virus (AIV).In this study,the expression of eleven housekeeping gen...Chicken embryo fibroblasts (CEFs) are among the most commonly used cells for the study of interactions between chicken hosts and H5N1 avian influenza virus (AIV).In this study,the expression of eleven housekeeping genes typically used for the normalization of quantitative real-time PCR (QPCR) analysis in mammals were compared in CEFs infected with H5N1 AIV to determine the most reliable reference genes in this system.CEFs cultured from 10-day-old SPF chicken embryos were infected with 100 TCID50 of H5N1 AIV and harvested at 3,12,24 and 30 hours post-infection.The expression levels of the eleven reference genes in infected and uninfected CEFs were determined by real-time PCR.Based on expression stability and expression levels,our data suggest that the ribosomal protein L4 (RPL4) and tyrosine 3-monooxygenase tryptophan 5-monooxygenase activation protein zeta polypeptide (YWHAZ) are the best reference genes to use in the study of host cell response to H5N1 AIV infection.However,for the study of replication levels of H5N1 AIV in CEFs,the β-actin gene (ACTB) and the ribosomal protein L4 (RPL4) gene are the best references.展开更多
The demand for efficient and environmentally-benign electrocatalysts that help availably harness the renewable energy resources is growing rapidly. In recent years, increasing insights into the design of water electro...The demand for efficient and environmentally-benign electrocatalysts that help availably harness the renewable energy resources is growing rapidly. In recent years, increasing insights into the design of water electrolysers, fuel cells, and metal–air batteries emerge in response to the need for developing sustainable energy carriers, in which the oxygen evolution reaction and the oxygen reduction reaction play key roles. However, both reactions suffer from sluggish kinetics that restricts the reactivity. Therefore, it is vital to probe into the structure of the catalysts to exploit high-performance bifunctional oxygen electrocatalysts. Spinel-type catalysts are a class of materials with advantages of versatility, low toxicity, low expense, high abundance, flexible ion arrangement, and multivalence structure. In this review, we afford a basic overview of spinel-type materials and then introduce the relevant theoretical principles for electrocatalytic activity, following that we shed light on the structure–property relationship strategies for spinel-type catalysts including electronic structure, microstructure, phase and composition regulation,and coupling with electrically conductive supports. We elaborate the relationship between structure and property, in order to provide some insights into the design of spinel-type bifunctional oxygen electrocatalysts.展开更多
BACKGROUND Microvascular invasion(MVI)of small hepatocellular carcinoma(sHCC)(≤3.0 cm)is an independent prognostic factor for poor progression-free and overall survival.Radiomics can help extract imaging information ...BACKGROUND Microvascular invasion(MVI)of small hepatocellular carcinoma(sHCC)(≤3.0 cm)is an independent prognostic factor for poor progression-free and overall survival.Radiomics can help extract imaging information associated with tumor pathophysiology.AIM To develop and validate radiomics scores and a nomogram of gadolinium ethoxybenzyl-diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)-enhanced magnetic resonance imaging(MRI)for preoperative prediction of MVI in sHCC.METHODS In total,415 patients were diagnosed with sHCC by postoperative pathology.A total of 221 patients were retrospectively included from our hospital.In addition,we recruited 94 and 100 participants as independent external validation sets from two other hospitals.Radiomics models of Gd-EOB-DTPA-enhanced MRI and diffusion-weighted imaging(DWI)were constructed and validated using machine learning.As presented in the radiomics nomogram,a prediction model was developed using multivariable logistic regression analysis,which included radiomics scores,radiologic features,and clinical features,such as the alpha-fetoprotein(AFP)level.The calibration,decision-making curve,and clinical usefulness of the radiomics nomogram were analyzed.The radiomic nomogram was validated using independent external cohort data.The areas under the receiver operating curve(AUC)were used to assess the predictive capability.RESULTS Pathological examination confirmed MVI in 64(28.9%),22(23.4%),and 16(16.0%)of the 221,94,and 100 patients,respectively.AFP,tumor size,non-smooth tumor margin,incomplete capsule,and peritumoral hypointensity in hepatobiliary phase(HBP)images had poor diagnostic value for MVI of sHCC.Quantitative radiomic features(1409)of MRI scans)were extracted.The classifier of logistic regression(LR)was the best machine learning method,and the radiomics scores of HBP and DWI had great diagnostic efficiency for the prediction of MVI in both the testing set(hospital A)and validation set(hospital B,C).The AUC of HBP was 0.979,0.970,and 0.803,respectively,and the AUC of DWI was 0.971,0.816,and 0.801(P<0.05),respectively.Good calibration and discrimination of the radiomics and clinical combined nomogram model were exhibited in the testing and two external validation cohorts(C-index of HBP and DWI were 0.971,0.912,0.808,and 0.970,0.843,0.869,respectively).The clinical usefulness of the nomogram was further confirmed using decision curve analysis.CONCLUSION AFP and conventional Gd-EOB-DTPA-enhanced MRI features have poor diagnostic accuracies for MVI in patients with sHCC.Machine learning with an LR classifier yielded the best radiomics score for HBP and DWI.The radiomics nomogram developed as a noninvasive preoperative prediction method showed favorable predictive accuracy for evaluating MVI in sHCC.展开更多
Electrocatalytic oxygen reduction reaction (ORR) via two-electron pathway is a promising approach to decentralized and on-site hydrogen peroxide (H_(2)O_(2)) production beyond the traditional anthraquinone process.In ...Electrocatalytic oxygen reduction reaction (ORR) via two-electron pathway is a promising approach to decentralized and on-site hydrogen peroxide (H_(2)O_(2)) production beyond the traditional anthraquinone process.In recent years,electrochemical H_(2)O_(2) production in acidic media has attracted increasing attention owing to its stronger oxidizing capacity,superior stability,and higher compatibility with various applications.Here,recent advances of H_(2)O_(2) electrosynthesis in acidic media are summarized.Specifically,fundamental aspects of two-electron ORR mechanism are firstly presented with an emphasis on the pH effect on catalytic performance.Major categories of promising electrocatalysts are then reviewed,including noble-metal-based materials,non-noble-metal single-atom catalysts,non-noblemetal compounds,and metal-free carbon-based materials.The innovative development of electrochemical devices and in situ/on-site application of electrogenerated H_(2)O_(2) are also highlighted to bridge the gap between laboratory-scale fundamental research and practically relevant H_(2)O_(2) electrosynthesis.Finally,critical perspectives on present challenges and promising opportunities for future research are provided.展开更多
To satisfy the rapid development of gas-involving electrocatalysis(O2, CO2, N2, etc.), nanostructured electrocatalysts with favorably regulated electronic structure and surface nanostructures are urgently required. He...To satisfy the rapid development of gas-involving electrocatalysis(O2, CO2, N2, etc.), nanostructured electrocatalysts with favorably regulated electronic structure and surface nanostructures are urgently required. Herein, we highlighted a core-branch hydroxysulfide as a significantly enhanced oxygen evolution reaction electrocatalyst. This hydroxysulfide was facilely fabricated via a versatile interfacial reaction in S2- inorganic solution at room temperature for a designed period. The moderative growth kinetics contributed to the growth of interconnected hydroxysulfide nanosheets with high-sulfur contents on the hydroxide precursor substrates, resulting in a hierarchical nanostructure with multifunctional modifications, including regulated electronic structure, rapid electron highway, excellent accessibility, and facilitated mass transfer. Such synthetic methodology can be generalized and facilely governed by regulating the temperature, concentration, duration, and solvent for targeted nanostructures. Contributed to the favorably regulated electronic structure and surface nanostructure, the as-obtained core-branch Co2NiS2.4(OH)1.2 sample exhibits superior OER performance, with a remarkably low overpotential(279 m V required for 10.0 m A c^m-2), a low Tafel slope(52 m V dec^-1), and a favorable long-term stability. This work not only presents a promising nanostructured hydroxysulfide for excellent OER electrocatalysis, but also shed fresh lights on the further rational development of efficient electrocatalysts.展开更多
In recent years, structure design and predictions based on global optimization approach as implemented in CALYPSO software have gained great success in accelerating the discovery of novel two-dimensional(2D) materials...In recent years, structure design and predictions based on global optimization approach as implemented in CALYPSO software have gained great success in accelerating the discovery of novel two-dimensional(2D) materials. Here we highlight some most recent research progress on the prediction of novel 2D structures, involving elements, metal-free and metal-containing compounds using CALYPSO package. Particular emphasis will be given to those 2D materials that exhibit unique electronic and magnetic properties with great potentials for applications in novel electronics, optoelectronics,magnetronics, spintronics, and photovoltaics. Finally, we also comment on the challenges and perspectives for future discovery of multi-functional 2D materials.展开更多
Biomass-derived carbon materials are widely applied in the energy storage and conversion fields due to their rich sources,low price and environmental friendliness.Herein,a unique pumpkin-like MoPMoS_(2)@Aspergillus ni...Biomass-derived carbon materials are widely applied in the energy storage and conversion fields due to their rich sources,low price and environmental friendliness.Herein,a unique pumpkin-like MoPMoS_(2)@Aspergillus niger spore-derived N-doped carbon(SNC)composite has been prepared via a simple hydrothermal and subsequent phosphorization process.Interestingly,the resulting MoP-MoS_(2)@SNC well inherits the pristine morphology of spore carbon,similar to the natural pumpkin,with hollow interiors and uneven protrusions on the surface.The special structure allows it to have sufficient space to fully contact the electrolyte and greatly reduces the ion transport distance.The theory calculations further demonstrate that the formed MoP-MoS_(2)heterostructure can enhance the adsorption of K ions and electronic couplings.With these unique advantages,the MoP-MoS_(2)@SNC anode for potassium storage shows a high reversible capability of 286.2 mAh g&(-1) at 100 mA g^(-1) after 100 cycles and superior rate performance.The enhanced electrochemical performance is mainly related to the unique pumpkin-like morphology of SNC and the construction of MoP-MoS_(2)heterostructure,as well as their perfect coupling.This study provides a feasible design idea for developing green,low-cost,and high-performance electrode materials for next-generation energy storage.展开更多
Single-atom catalysts serve as a promising candidate to realize noble-metal-free electrocatalytic oxygen reduction in acid media.However,their poor stability under working conditions strictly restrains their practical...Single-atom catalysts serve as a promising candidate to realize noble-metal-free electrocatalytic oxygen reduction in acid media.However,their poor stability under working conditions strictly restrains their practical applications.Therefore,regeneration of their electrocatalytic activity is of great significance.Herein,the regeneration of a Fe-N-C single-atom catalyst is demonstrated to be feasible by a facile annealing regeneration strategy.The activity after regeneration recovers to that of the pristine electrocatalyst and surpasses the deactivated electrocatalyst.The regeneration mechanism is identified to be selfetching of the surface carbon layer and consequent exposure of the previously buried single-atom sites.Furthermore,the regeneration strategy is applicable to other single-atom catalysts.This work demonstrates the feasibility of regenerating oxygen reduction electrocatalysts and affords a pioneering approach to deal with rapid deactivation under working conditions.展开更多
The introduction of nitrogen heteroatoms into carbon materials is a facile and efficient strategy to regulate their reactivities and facilitate their potential applications in energy conversion and storage. However,mo...The introduction of nitrogen heteroatoms into carbon materials is a facile and efficient strategy to regulate their reactivities and facilitate their potential applications in energy conversion and storage. However,most of nitrogen heteroatoms are doped into the bulk phase of carbon without site selectivity, which significantly reduces the contacts of feedstocks with the active dopants in a conductive scaffold. Herein we proposed the chemical vapor deposition of a nitrogen-doped graphene skin on the 3D porous graphene framework and donated the carbon/carbon composite as surface N-doped grapheme(SNG). In contrast with routine N-doped graphene framework(NGF) with bulk distribution of N heteroatoms, the SNG renders a high surface N content of 1.81 at%, enhanced electrical conductivity of 31 S cm^(-1), a large surface area of 1531 m^2 g^(-1), a low defect density with a low I_D/I_G ratio of 1.55 calculated from Raman spectrum, and a high oxidation peak of 532.7 ℃ in oxygen atmosphere. The selective distribution of N heteroatoms on the surface of SNG affords the effective exposure of active sites at the interfaces of the electrode/electrolyte, so that more N heteroatoms are able to contact with oxygen feedstocks in oxygen reduction reaction or serve as polysulfide anchoring sites to retard the shuttle of polysulfides in a lithium–sulfur battery. This work opens a fresh viewpoint on the manipulation of active site distribution in a conductive scaffolds for multi-electron redox reaction based energy conversion and storage.展开更多
基金supported by the National Natural Science Foundation of China(T2322015,22209094,22209093,and 22109086)the National Key Research and Development Program(2021YFB2500300)+2 种基金the Open Research Fund of CNMGE Platform&NSCC-TJOrdos-Tsinghua Innovative&Collaborative Research Program in Carbon Neutralitythe Tsinghua University Initiative Scientific Research Program。
文摘Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium batteries.However,atomic insights into the EDL structures on heteroatom-modified graphite anodes and EDL evolution with electrode potential are very lacking.Herein,a constant-potential molecular dynamics(CPMD)method is proposed to probe the EDL structure under working conditions,taking N-doped graphite electrodes and carbonate electrolytes as an example.An interface model was developed,incorporating the electrode potential and atom electronegativities.As a result,an insightful atomic scenario for the EDL structure under varied electrode potentials has been established,which unveils the important role of doping sites in regulating both the EDL structures and the following electrochemical reactions at the atomic level.Specifically,the negatively charged N atoms repel the anions and adsorb Li~+at high and low potentials,respectively.Such preferential adsorption suggests that Ndoped graphite can promote Li~+desolvation and regulate the location of Li~+deposition.This CPMD method not only unveils the mysterious function of N-doping from the viewpoint of EDL at the atomic level but also applies to probe the interfacial structure on other complicated electrodes.
基金sponsored by the Southwest Minzu University Double World-Class ProjectChina(XM2023014)+3 种基金the Sichuan Veterinary Medicine and Drug Innovation Group of China Agricultural Research System(SCCXTD-2020-18)the Key Laboratory of Veterinary Medicine of Universities of Sichuan Province of Chinathe Fundamental Research Funds for the Central UniversitiesSouthwest Minzu University China(ZYN2023043)。
文摘Kobuvirus comprises 6 officially recognized species,namely Aichivirus A-F,and can be further divided into 20 genotypes through VP1 gene phylogenetic analysis(https://ictv.global/report/chapter/picornaviridae/picornaviridae/kobuvirus).Aichivirus A in human,Aichivirus B in bovine,Aichivirus C in porcine and caprine,Aichivirus D in yak have been proved to be associated with diarrhea(Chen Y S et al.2013;Yang et al.2015;Zhu et al.2016;Zhai et al.2017;Wang et al.2020;Abi et al.2022;Yan et al.2023).
基金supported by National Key Research and Development Program (2021YFB2400300)Beijing Natural Science Foundation (JQ20004)+1 种基金the National Natural Science Foundation of China (22109011, U1801257)Scientific and Technological Key Project of Shanxi Province (20191102003)。
文摘Lithium metal anode(LMA) is a promising candidate for achieving next-generation high-energy-density batteries due to its ultrahigh theoretical capacity and most negative electrochemical potential. However, the practical application of lithium metal battery(LMB) is largely retarded by the instable interfaces, uncontrolled dendrites, and rapid capacity deterioration. Herein, we present a comprehensive overview towards the working principles and inherent challenges of LMAs. Firstly, we diligently summarize the intrinsic mechanism of Li stripping and plating process. The recent advances in atomic and mesoscale simulations which are crucial in guiding mechanism study and material design are also summarized. Furthermore, the advanced engineering strategies which have been proved effective in protecting LMAs are systematically reviewed, including electrolyte optimization, artificial interface, composite/alloy anodes and so on. Finally, we highlight the current limitations and promising research directions of LMAs. This review sheds new lights on deeply understanding the intrinsic mechanism of LMAs, and calls for more endeavors to realize practical Li metal batteries.
基金National Natural Science Foundation of China(52072297 and 51907149)Key R&D Plan of Shaanxi Province(2021GXLH-Z-068)+1 种基金China Postdoctoral Science Foundation(2019M653609)the Young Talent Support Plan of Xi’an Jiaotong University。
文摘The advance of microelectronics requires the micropower of microsupercapacitors(MSCs) to possess wide temperature-and damage-tolerance beyond high areal energy density.The properties of electrolyte are crucial for MSCs to meet the above requirements.Here,an organohydrogel electrolyte,featured with high salt tolerance,ultralow freezing point,and strong self-healing ability,is experimentally realized via modulating its inner dynamic bonds.Spectroscopic and theoretical analysis reveal that dimethyl sulfoxide has the ability to reconstruct Li^(+)solvation structure,and interact with free water and polyvinyl alcohol chains via forming hydrogen bonds.The organohydrogel electrolyte is employed to build MSCs,which show a boosted energy density,promising wide temperature range-and damage-tolerant ability.These attractive features make the designed organohydrogel electrolyte have great potential to advance MSCs.
基金supported by the National Natural Science Foundation of China(51962002)the Natural Science Foundation of Guangxi(2022GXNSFAA035463)the National Key R&D Program of China(2022YFB2404402)。
文摘Lithium-sulfur(Li-S)batteries have attracted wide attention for their high theoretical energy density,low cost,and environmental friendliness.However,the shuttle effect of polysulfides and the insulation of active materials severely restrict the development of Li-S batteries.Constructing conductive sulfur scaffolds with catalytic conversion capability for cathodes is an efficient approach to solving above issues.Vanadium-based compounds and their heterostructures have recently emerged as functional sulfur catalysts supported on conductive scaffolds.These compounds interact with polysulfides via different mechanisms to alleviate the shuttle effect and accelerate the redox kinetics,leading to higher Coulombic efficiency and enhanced sulfur utilization.Reports on vanadium-based nanomaterials in Li-S batteries have been steadily increasing over the past several years.In this review,first,we provide an overview of the synthesis of vanadium-based compounds and heterostructures.Then,we discuss the interactions and constitutive relationships between vanadium-based catalysts and polysulfides formed at sulfur cathodes.We summarize the mechanisms that contribute to the enhancement of electrochemical performance for various types of vanadium-based catalysts,thus providing insights for the rational design of sulfur catalysts.Finally,we offer a perspective on the future directions for the research and development of vanadium-based sulfur catalysts.
基金the National Science Foundation for Excellent Young Scholars of China(21922815)the National Natural Science Foundation of China(22179139)+2 种基金the National Key Research and Development Program of China(2020YFB1505800)the Youth Innovation Promotion Association of CAS(2019178)the“Transformational Technologies for Clean Energy and Demonstration”Strategic Priority Research Program of the CAS(XDA21000000)。
文摘N-doped porous carbon has been extensively investigated for broad electrochemical applications.The performance is significantly impacted by the electrochemical double layer(EDL),which is material dependent and hard to characterize.Limited understanding of doping-derived EDL structure hinders insight into the structure-performance relations and the rational design of high-performance materials.Thus,we analyzed the mass and chemical composition variation of EDL within electrochemical operation by electrochemical quartz crystal microbalance,in-situ X-ray photoelectron spectroscopy,and time-offlight secondary ion mass spectrometry.We found that N-doping triggers specifically adsorbed propylene carbonate solvent in the inner Helmholtz plane(IHP),which prevents ion rearrangement and enhances the migration of cations.However,this specific adsorption accelerated solvent decomposition,rendering rapid performance degradation in practical devices.This work reveals that the surface chemistry of electrodes can cause specific adsorption of solvents and change the EDL structure,which complements the classical EDL theory and provide guidance for practical applications.
基金supported by the National Natural Science Foundation of China(21825501)the Ordos–Tsinghua Innovative and Collaborative Research Program in Carbon Neutrality。
文摘1.Introduction Achieving carbon neutrality and sustainable development demands an extensive and profound systemic reform of China’s energy,industry,and economy structures.According to statistics[1,2],almost 90%of CO_(2) emissions in China come from the energy sector,with the leading emission sources being power(48%),industry(36%),transport(8%),and buildings(5%)[1].
基金Funded by the National Natural Science Foundation of China(No.51701187)the Basic Applied Research Projects in Shanxi Province(201801D221151)。
文摘The Cu_(65)Ni_(35) alloy liquid was undercooled by the fluxing method,and the rapid solidification structure was obtained by natural cooling.The solidification interface migration information of Cu_(65)Ni_(35) alloy liquid in rapid solidification stage was photographed with the help of high-speed camera,and the recalescence velocity was calculated.The microstructure evolution of the alloy was systematically studied by observing the microstructure morphology and taking photos on the metallographic microscope.By analyzing the evolution of dendrite grain size and microstructure microhardness with undercoolingand relying on electron backscatter diffraction(EBSD)technology,the grain refinement mechanism of microstructure under high undercooling and low undercooling is finally confirmed.
基金supported by the National Key Research and Development Program (Nos. 2016YFA0202500 and 2016YFA0200102)the Natural Scientific Foundation of China (No. 21561130151)Royal Society for the award of a Newton Advanced Fellowship (Ref: NA140249)
文摘Nanocarbons are of progressively increasing importance in energy electrocatalysis, including oxygen reduction, oxygen evolution, hydrogen evolution, COreduction, etc. Precious-metal-free or metal-free nanocarbon-based electrocatalysts have been revealed to potentially have effective activity and remarkable durability, which is promising to replace precious metals in some important energy technologies,such as fuel cells, metal–air batteries, and water splitting. In this review, rather than overviewing recent progress completely, we aim to give an in-depth digestion of present achievements, focusing on the different roles of nanocarbons and material design principles. The multifunctionalities of nanocarbon substrates(accelerating the electron and mass transport, regulating the incorporation of active components,manipulating electron structures, generating confinement effects, assembly into 3 D free-standing electrodes) and the intrinsic activity of nanocarbon catalysts(multi-heteroatom doping, hierarchical structure,topological defects) are discussed systematically, with perspectives on the further research in this rising research field. This review is inspiring for more insights and methodical research in mechanism understanding, material design, and device optimization, leading to a targeted and high-efficiency development of energy electrocatalysis.
基金National "11th Five-year Plan" Scientific and Technical Supporting Programs (2006BAD06A11)
文摘Chicken embryo fibroblasts (CEFs) are among the most commonly used cells for the study of interactions between chicken hosts and H5N1 avian influenza virus (AIV).In this study,the expression of eleven housekeeping genes typically used for the normalization of quantitative real-time PCR (QPCR) analysis in mammals were compared in CEFs infected with H5N1 AIV to determine the most reliable reference genes in this system.CEFs cultured from 10-day-old SPF chicken embryos were infected with 100 TCID50 of H5N1 AIV and harvested at 3,12,24 and 30 hours post-infection.The expression levels of the eleven reference genes in infected and uninfected CEFs were determined by real-time PCR.Based on expression stability and expression levels,our data suggest that the ribosomal protein L4 (RPL4) and tyrosine 3-monooxygenase tryptophan 5-monooxygenase activation protein zeta polypeptide (YWHAZ) are the best reference genes to use in the study of host cell response to H5N1 AIV infection.However,for the study of replication levels of H5N1 AIV in CEFs,the β-actin gene (ACTB) and the ribosomal protein L4 (RPL4) gene are the best references.
基金supported by the Natural Scientific Foundation of China (21825501)National Key Research and Development Program (2016YFA0202500 and 2016YFA0200102)+1 种基金Australian Research Council (DP160103107, FT170100224)Tsinghua University Initiative Scientific Research Program。
文摘The demand for efficient and environmentally-benign electrocatalysts that help availably harness the renewable energy resources is growing rapidly. In recent years, increasing insights into the design of water electrolysers, fuel cells, and metal–air batteries emerge in response to the need for developing sustainable energy carriers, in which the oxygen evolution reaction and the oxygen reduction reaction play key roles. However, both reactions suffer from sluggish kinetics that restricts the reactivity. Therefore, it is vital to probe into the structure of the catalysts to exploit high-performance bifunctional oxygen electrocatalysts. Spinel-type catalysts are a class of materials with advantages of versatility, low toxicity, low expense, high abundance, flexible ion arrangement, and multivalence structure. In this review, we afford a basic overview of spinel-type materials and then introduce the relevant theoretical principles for electrocatalytic activity, following that we shed light on the structure–property relationship strategies for spinel-type catalysts including electronic structure, microstructure, phase and composition regulation,and coupling with electrically conductive supports. We elaborate the relationship between structure and property, in order to provide some insights into the design of spinel-type bifunctional oxygen electrocatalysts.
基金Supported by the National Natural Science Foundation of China,No.82060310Science and Technology Support Program of Sichuan Province,No.2022YFS0071。
文摘BACKGROUND Microvascular invasion(MVI)of small hepatocellular carcinoma(sHCC)(≤3.0 cm)is an independent prognostic factor for poor progression-free and overall survival.Radiomics can help extract imaging information associated with tumor pathophysiology.AIM To develop and validate radiomics scores and a nomogram of gadolinium ethoxybenzyl-diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)-enhanced magnetic resonance imaging(MRI)for preoperative prediction of MVI in sHCC.METHODS In total,415 patients were diagnosed with sHCC by postoperative pathology.A total of 221 patients were retrospectively included from our hospital.In addition,we recruited 94 and 100 participants as independent external validation sets from two other hospitals.Radiomics models of Gd-EOB-DTPA-enhanced MRI and diffusion-weighted imaging(DWI)were constructed and validated using machine learning.As presented in the radiomics nomogram,a prediction model was developed using multivariable logistic regression analysis,which included radiomics scores,radiologic features,and clinical features,such as the alpha-fetoprotein(AFP)level.The calibration,decision-making curve,and clinical usefulness of the radiomics nomogram were analyzed.The radiomic nomogram was validated using independent external cohort data.The areas under the receiver operating curve(AUC)were used to assess the predictive capability.RESULTS Pathological examination confirmed MVI in 64(28.9%),22(23.4%),and 16(16.0%)of the 221,94,and 100 patients,respectively.AFP,tumor size,non-smooth tumor margin,incomplete capsule,and peritumoral hypointensity in hepatobiliary phase(HBP)images had poor diagnostic value for MVI of sHCC.Quantitative radiomic features(1409)of MRI scans)were extracted.The classifier of logistic regression(LR)was the best machine learning method,and the radiomics scores of HBP and DWI had great diagnostic efficiency for the prediction of MVI in both the testing set(hospital A)and validation set(hospital B,C).The AUC of HBP was 0.979,0.970,and 0.803,respectively,and the AUC of DWI was 0.971,0.816,and 0.801(P<0.05),respectively.Good calibration and discrimination of the radiomics and clinical combined nomogram model were exhibited in the testing and two external validation cohorts(C-index of HBP and DWI were 0.971,0.912,0.808,and 0.970,0.843,0.869,respectively).The clinical usefulness of the nomogram was further confirmed using decision curve analysis.CONCLUSION AFP and conventional Gd-EOB-DTPA-enhanced MRI features have poor diagnostic accuracies for MVI in patients with sHCC.Machine learning with an LR classifier yielded the best radiomics score for HBP and DWI.The radiomics nomogram developed as a noninvasive preoperative prediction method showed favorable predictive accuracy for evaluating MVI in sHCC.
基金The University of Adelaide for Early Career Researcher Seed Funding(15128587)the University of Electronic Science and Technology of China(UESTC)for Startup funding(A1098531023601264)the National Natural Science Foundation of China(NSFC 22102018 and 52171201)。
文摘Electrocatalytic oxygen reduction reaction (ORR) via two-electron pathway is a promising approach to decentralized and on-site hydrogen peroxide (H_(2)O_(2)) production beyond the traditional anthraquinone process.In recent years,electrochemical H_(2)O_(2) production in acidic media has attracted increasing attention owing to its stronger oxidizing capacity,superior stability,and higher compatibility with various applications.Here,recent advances of H_(2)O_(2) electrosynthesis in acidic media are summarized.Specifically,fundamental aspects of two-electron ORR mechanism are firstly presented with an emphasis on the pH effect on catalytic performance.Major categories of promising electrocatalysts are then reviewed,including noble-metal-based materials,non-noble-metal single-atom catalysts,non-noblemetal compounds,and metal-free carbon-based materials.The innovative development of electrochemical devices and in situ/on-site application of electrogenerated H_(2)O_(2) are also highlighted to bridge the gap between laboratory-scale fundamental research and practically relevant H_(2)O_(2) electrosynthesis.Finally,critical perspectives on present challenges and promising opportunities for future research are provided.
基金supported by the National Key Research and Development Program(2016YFA0202500 and 2016YFA0200101)the Natural Scientific Foundation of China(21825501)
文摘To satisfy the rapid development of gas-involving electrocatalysis(O2, CO2, N2, etc.), nanostructured electrocatalysts with favorably regulated electronic structure and surface nanostructures are urgently required. Herein, we highlighted a core-branch hydroxysulfide as a significantly enhanced oxygen evolution reaction electrocatalyst. This hydroxysulfide was facilely fabricated via a versatile interfacial reaction in S2- inorganic solution at room temperature for a designed period. The moderative growth kinetics contributed to the growth of interconnected hydroxysulfide nanosheets with high-sulfur contents on the hydroxide precursor substrates, resulting in a hierarchical nanostructure with multifunctional modifications, including regulated electronic structure, rapid electron highway, excellent accessibility, and facilitated mass transfer. Such synthetic methodology can be generalized and facilely governed by regulating the temperature, concentration, duration, and solvent for targeted nanostructures. Contributed to the favorably regulated electronic structure and surface nanostructure, the as-obtained core-branch Co2NiS2.4(OH)1.2 sample exhibits superior OER performance, with a remarkably low overpotential(279 m V required for 10.0 m A c^m-2), a low Tafel slope(52 m V dec^-1), and a favorable long-term stability. This work not only presents a promising nanostructured hydroxysulfide for excellent OER electrocatalysis, but also shed fresh lights on the further rational development of efficient electrocatalysts.
基金support by Australian Research Council under Discovery Project (Grant No. DP170103598)the Pawsey Supercomputing Centre through the National Computational Merit Allocation Scheme supported by the Australian Government and the Government of Western Australia
文摘In recent years, structure design and predictions based on global optimization approach as implemented in CALYPSO software have gained great success in accelerating the discovery of novel two-dimensional(2D) materials. Here we highlight some most recent research progress on the prediction of novel 2D structures, involving elements, metal-free and metal-containing compounds using CALYPSO package. Particular emphasis will be given to those 2D materials that exhibit unique electronic and magnetic properties with great potentials for applications in novel electronics, optoelectronics,magnetronics, spintronics, and photovoltaics. Finally, we also comment on the challenges and perspectives for future discovery of multi-functional 2D materials.
基金the support from the Shuguang Program supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(18SG035)the Basic Research Program of Shanghai Municipal Government(21JC1406002)the Shanghai Engineering Research Center of Advanced Thermal Functional Materials(Shanghai Polytechnic University)。
文摘Biomass-derived carbon materials are widely applied in the energy storage and conversion fields due to their rich sources,low price and environmental friendliness.Herein,a unique pumpkin-like MoPMoS_(2)@Aspergillus niger spore-derived N-doped carbon(SNC)composite has been prepared via a simple hydrothermal and subsequent phosphorization process.Interestingly,the resulting MoP-MoS_(2)@SNC well inherits the pristine morphology of spore carbon,similar to the natural pumpkin,with hollow interiors and uneven protrusions on the surface.The special structure allows it to have sufficient space to fully contact the electrolyte and greatly reduces the ion transport distance.The theory calculations further demonstrate that the formed MoP-MoS_(2)heterostructure can enhance the adsorption of K ions and electronic couplings.With these unique advantages,the MoP-MoS_(2)@SNC anode for potassium storage shows a high reversible capability of 286.2 mAh g&(-1) at 100 mA g^(-1) after 100 cycles and superior rate performance.The enhanced electrochemical performance is mainly related to the unique pumpkin-like morphology of SNC and the construction of MoP-MoS_(2)heterostructure,as well as their perfect coupling.This study provides a feasible design idea for developing green,low-cost,and high-performance electrode materials for next-generation energy storage.
基金supported by the National Natural Science Foundation of China(22109007 and 21825501)Beijing Institute of Technology Research Fund Program for Young Scholarsthe Tsinghua University Initiative Scientific Research Program。
文摘Single-atom catalysts serve as a promising candidate to realize noble-metal-free electrocatalytic oxygen reduction in acid media.However,their poor stability under working conditions strictly restrains their practical applications.Therefore,regeneration of their electrocatalytic activity is of great significance.Herein,the regeneration of a Fe-N-C single-atom catalyst is demonstrated to be feasible by a facile annealing regeneration strategy.The activity after regeneration recovers to that of the pristine electrocatalyst and surpasses the deactivated electrocatalyst.The regeneration mechanism is identified to be selfetching of the surface carbon layer and consequent exposure of the previously buried single-atom sites.Furthermore,the regeneration strategy is applicable to other single-atom catalysts.This work demonstrates the feasibility of regenerating oxygen reduction electrocatalysts and affords a pioneering approach to deal with rapid deactivation under working conditions.
基金supported by the National Key Research and Development Program(2016YFA0202500 and 2016YFA0200102)the Natural Scientific Foundation of China(21776019)
文摘The introduction of nitrogen heteroatoms into carbon materials is a facile and efficient strategy to regulate their reactivities and facilitate their potential applications in energy conversion and storage. However,most of nitrogen heteroatoms are doped into the bulk phase of carbon without site selectivity, which significantly reduces the contacts of feedstocks with the active dopants in a conductive scaffold. Herein we proposed the chemical vapor deposition of a nitrogen-doped graphene skin on the 3D porous graphene framework and donated the carbon/carbon composite as surface N-doped grapheme(SNG). In contrast with routine N-doped graphene framework(NGF) with bulk distribution of N heteroatoms, the SNG renders a high surface N content of 1.81 at%, enhanced electrical conductivity of 31 S cm^(-1), a large surface area of 1531 m^2 g^(-1), a low defect density with a low I_D/I_G ratio of 1.55 calculated from Raman spectrum, and a high oxidation peak of 532.7 ℃ in oxygen atmosphere. The selective distribution of N heteroatoms on the surface of SNG affords the effective exposure of active sites at the interfaces of the electrode/electrolyte, so that more N heteroatoms are able to contact with oxygen feedstocks in oxygen reduction reaction or serve as polysulfide anchoring sites to retard the shuttle of polysulfides in a lithium–sulfur battery. This work opens a fresh viewpoint on the manipulation of active site distribution in a conductive scaffolds for multi-electron redox reaction based energy conversion and storage.