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
TiO_(2)has been widely studied as one of the most promising anode materials for lithium-ion batteries(LIBs)due to good structural stability and small volume changes.However,its applications are still greatly affected ...TiO_(2)has been widely studied as one of the most promising anode materials for lithium-ion batteries(LIBs)due to good structural stability and small volume changes.However,its applications are still greatly affected by its poor electrical conductivity.In this work,ultrasmall TiO_(2)quantum dots(QDs)are firmly grown onto 2D Ti_(3)C_(2)T_(x)nanosheets(A-TiO_(2)/Ti_(3)C_(2)T_(x)),benefiting from the positive regulation of(3-aminopropyl)triethoxysilane(APTES).Interestingly,SiO_(2)nanoparticles produced by the hydrolysis of APTES can strengthen the strong coupling of TiO_(2)QDs with Ti_(3)C_(2)T_(x),thereby enhancing the structural integrity of the composite.As expected,the A-TiO_(2)/Ti_(3)C_(2)T_(x)composite demonstrates an exceptional lithium storage performance,achieving a high capacity of 425.4 m Ah/g for 400 cycles at 0.1 A/g,and an outstanding long-term cycling stability.In-situ electrochemical impedance spectroscopy and theoretical analysis unconver that the superior lithium storage performance is attributed to its unique heterostructure and in-situ N doping derived from APTES,which not only reduces the Li^(+)adsorption energy,but also gives the fast charge transfer dynamics.展开更多
TiNb_(2)O_(7)has been emerged as one of the most promising electrode materials for high-energy lithium-ion batteries.However,limited by the slow electron/ion transport kinetics,and insufficient active sites in the bul...TiNb_(2)O_(7)has been emerged as one of the most promising electrode materials for high-energy lithium-ion batteries.However,limited by the slow electron/ion transport kinetics,and insufficient active sites in the bulk structure,the TiNb_(2)O_(7)electrode still suffers from unsatisfactory lithium storage performance.Herein,we demonstrate a spatially confined strategy toward a novel TiNb_(2)O_(7)-NMC/MXene composite through a triblock copolymer-directed one-pot solvothermal route,where TiNb_(2)O_(7)quantum dots with a particle size of 2-3 nm are evenly embedded into N-doped mesoporous carbon(NMC)and Ti_(3)C_(2)T_(X)MXene.Impressively,the as-prepared TiNb_(2)O_(7)-NMC/MXene anode exhibits a high reversible capacity(486.2 mAh g^(-1)at 0.1 A g^(-1)after 100 cycles)and long cycle lifespan(363.4 mAh g^(-1)at ss1 A g^(-1)after 500 cycles).Both experimental and theorical results further demonstrate that such a superior lithium storage performance is mainly ascribed to the synergistic effect among 0D TiNb_(2)O_(7)quantum dots,2D Ti_(3)C_(2)T_(X)MXene nanosheets,and N-doped mesoporous carbon.The strategy presented also opens up new horizon for space-confined preparation of high-performance electrode materials.展开更多
Electrochemical nitrogen transformation techniques represent a burgeoning avenue for nitrogen pollutant remediation and synthesizing valuable nitrogenous products from atmospheric nitrogen.Intermetallic compounds(IMCs...Electrochemical nitrogen transformation techniques represent a burgeoning avenue for nitrogen pollutant remediation and synthesizing valuable nitrogenous products from atmospheric nitrogen.Intermetallic compounds(IMCs)nanocrystals,featured with unique geometric,electronic and functional properties,have emerged as promising candidates.The review discusses various synthesis approaches for IMCs,including thermal annealing,wet chemical synthesis,electrochemical synthesis,and other emerging methods,analyzing their advantages and limitations.Then we summarized the recent advances of IMCs in electrocatalytic nitrogen transformation reactions,such as nitrate reduction reaction,nitric oxide reduction reaction,nitrogen reduction reaction,and hydrazine oxidation reaction.Despite significant progress,challenges remain in the field,particularly in adopting more refined strategies to improve catalyst performance and stability.This review aims to comprehensively understand the structural properties of IMCs and their structure-performance relationship,guiding the development of more efficient and stable catalysts for future nitrogen electrochemistry.展开更多
5-Hydroxymethylfurfural(HMF),derived from biomass,is a promising sustainable resource that can be converted into valuable chemical compounds.One such compound,2,5-dihydroxymethylfuran(DHMF),produced through the electr...5-Hydroxymethylfurfural(HMF),derived from biomass,is a promising sustainable resource that can be converted into valuable chemical compounds.One such compound,2,5-dihydroxymethylfuran(DHMF),produced through the electrocatalytic hydrogenation of HMF,is widely used in industrial polymer manufacturing.However,the hydrogenation of high-concentration HMF remains challenging due to the tendency for undesirable dimerization.Acknowledging the critical role of adsorbed hydrogen(H*)in HMF hydrogenation,a series of transition metal-doped dual-cubic Cu electrocatalysts(M-Cu,where M=Mo,Pd,Pt,Au,and Ag)were synthesized to systematically investigate the effect of varying H*reactivity on HMF hydrogenation,A pronounced correlation between DHMF selectivity and H*coverage was observed.Increasing H*coverage can enhance the selectivity for DHMF and prevent undesired dimerization of adsorbed HMF molecules.While elevated H*coverage enhanced DHMF selectivity,excessive coverage adversely impacted Faradaic efficiency due to competing hydrogen evolution reaction.This underscores the critical importance of finely tuning H*coverage.The optimal electrocatalyst,achieved by fine-tuning the doping amount of Pt on Cu,demonstrated a Faradaic efficiency of over 90%for DHMF in highconcentration HMF at-0.3 V,marking the highest record reported to date.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
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
Hard carbons are widely investigated as potential anodes for lithium and sodium ion batteries owing to their internally well-tailored textures(closed pores and defects) and large microcrystalline interlayer spacing. T...Hard carbons are widely investigated as potential anodes for lithium and sodium ion batteries owing to their internally well-tailored textures(closed pores and defects) and large microcrystalline interlayer spacing. The renewable biomass is a green and economically attractive carbon source to produce hard carbons. However, the chemical and structural complexity of biomass has plagued the understanding of evolution mechanism from organic precursors to hard carbons and the structure-property relationship.This makes it difficult to finely tune the microstructure of biomass-derived hard carbons, thus greatly restricting their high-performance applications. Most recently, the optimal utilization and controllable conversion of biomass-derived biopolymers(such as starch, cellulose and lignin) at the molecular level have become a burgeoning area of research to develop hard carbons for advanced batteries.Considering the principal source of carbonaceous materials is from biomass pyrolysis, we firstly overview the chemical structures and pyrolysis behaviors of three main biopolymers. Then, the controllable preparation of hard carbons using various physicochemical properties of biopolymers at the molecular level is systematically discussed. Furthermore, we highlight present challenges and further opportunities in this field. The Review will guide future research works on the design of sustainable hard carbons and the optimization of battery performance.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
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
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
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 exploration of advanced MoS_(2)-based electrode materials overcoming their inherent low conductivity and large volume changes is of importance for next-generation energy storage.In this work,we report a simple and...The exploration of advanced MoS_(2)-based electrode materials overcoming their inherent low conductivity and large volume changes is of importance for next-generation energy storage.In this work,we report a simple and high-efficient one-pot hydrothermal approach to prepare a unique and stable 1D/2D heterostructure.In the architecture,ultrathin carbon layer-coated MoS_(2) nanosheets with large expanded interlayer of 1.02 nm are vertically grown onto the Ti_(3)C_(2) MXene and cross-linked carbon nanotubes(CNTs),giving rise to a highly conductive 3D network.The interlayer expanded MoS_(2) nanosheets can greatly facilitate the Na ions/electrons transmission.Meanwhile,the N-doped 1D/2D CNTs-Ti_(3)C_(2) matrix can be used as a strong mechanical support to well relieve the large volume expansion upon cycles.As a combination result of several advantages,the developed quaternary C-MoS_(2)/CNTs-Ti_(3)C_(2) composite anode shows an excellent sodium storage performance(562 mA h g^(-1) at 100 mA g^(-1) after 200 cycles)and rate capability(475 mA h g^(-1) at 2000 mA g^(-1)).The density functional theory calculations further prove that the full combination of layer-expanded MoS_(2) nanosheets and N-doped Ti_(3)C_(2) matrix can significantly enhance the adsorption energy of Na ions,further resulting in the enhancement of sodium storage capabilities.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
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
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
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support from the Natural Science Foundation of Shanghai(No.23ZR1423800)Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education),Nankai University。
文摘TiO_(2)has been widely studied as one of the most promising anode materials for lithium-ion batteries(LIBs)due to good structural stability and small volume changes.However,its applications are still greatly affected by its poor electrical conductivity.In this work,ultrasmall TiO_(2)quantum dots(QDs)are firmly grown onto 2D Ti_(3)C_(2)T_(x)nanosheets(A-TiO_(2)/Ti_(3)C_(2)T_(x)),benefiting from the positive regulation of(3-aminopropyl)triethoxysilane(APTES).Interestingly,SiO_(2)nanoparticles produced by the hydrolysis of APTES can strengthen the strong coupling of TiO_(2)QDs with Ti_(3)C_(2)T_(x),thereby enhancing the structural integrity of the composite.As expected,the A-TiO_(2)/Ti_(3)C_(2)T_(x)composite demonstrates an exceptional lithium storage performance,achieving a high capacity of 425.4 m Ah/g for 400 cycles at 0.1 A/g,and an outstanding long-term cycling stability.In-situ electrochemical impedance spectroscopy and theoretical analysis unconver that the superior lithium storage performance is attributed to its unique heterostructure and in-situ N doping derived from APTES,which not only reduces the Li^(+)adsorption energy,but also gives the fast charge transfer dynamics.
基金support from the Natural Science Foundation of Shanghai(23ZR1423800),Shuguang Program supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(18SG35)Open Research Fund of Shanghai Key Laboratory of Green Chemistry and Chemical Processes(East China Normal University)Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education),Nankai University.
文摘TiNb_(2)O_(7)has been emerged as one of the most promising electrode materials for high-energy lithium-ion batteries.However,limited by the slow electron/ion transport kinetics,and insufficient active sites in the bulk structure,the TiNb_(2)O_(7)electrode still suffers from unsatisfactory lithium storage performance.Herein,we demonstrate a spatially confined strategy toward a novel TiNb_(2)O_(7)-NMC/MXene composite through a triblock copolymer-directed one-pot solvothermal route,where TiNb_(2)O_(7)quantum dots with a particle size of 2-3 nm are evenly embedded into N-doped mesoporous carbon(NMC)and Ti_(3)C_(2)T_(X)MXene.Impressively,the as-prepared TiNb_(2)O_(7)-NMC/MXene anode exhibits a high reversible capacity(486.2 mAh g^(-1)at 0.1 A g^(-1)after 100 cycles)and long cycle lifespan(363.4 mAh g^(-1)at ss1 A g^(-1)after 500 cycles).Both experimental and theorical results further demonstrate that such a superior lithium storage performance is mainly ascribed to the synergistic effect among 0D TiNb_(2)O_(7)quantum dots,2D Ti_(3)C_(2)T_(X)MXene nanosheets,and N-doped mesoporous carbon.The strategy presented also opens up new horizon for space-confined preparation of high-performance electrode materials.
基金funded by the National Natural Science Foundation of China(No.22405173)the Shanghai Pujiang Program(No.23PJ1409100)the Project of Overseas Leading Talent of Shanghai.
文摘Electrochemical nitrogen transformation techniques represent a burgeoning avenue for nitrogen pollutant remediation and synthesizing valuable nitrogenous products from atmospheric nitrogen.Intermetallic compounds(IMCs)nanocrystals,featured with unique geometric,electronic and functional properties,have emerged as promising candidates.The review discusses various synthesis approaches for IMCs,including thermal annealing,wet chemical synthesis,electrochemical synthesis,and other emerging methods,analyzing their advantages and limitations.Then we summarized the recent advances of IMCs in electrocatalytic nitrogen transformation reactions,such as nitrate reduction reaction,nitric oxide reduction reaction,nitrogen reduction reaction,and hydrazine oxidation reaction.Despite significant progress,challenges remain in the field,particularly in adopting more refined strategies to improve catalyst performance and stability.This review aims to comprehensively understand the structural properties of IMCs and their structure-performance relationship,guiding the development of more efficient and stable catalysts for future nitrogen electrochemistry.
基金supported financially by the Australian Research Council(CE230100032,DP230102027,DP240102575,FT200100062)。
文摘5-Hydroxymethylfurfural(HMF),derived from biomass,is a promising sustainable resource that can be converted into valuable chemical compounds.One such compound,2,5-dihydroxymethylfuran(DHMF),produced through the electrocatalytic hydrogenation of HMF,is widely used in industrial polymer manufacturing.However,the hydrogenation of high-concentration HMF remains challenging due to the tendency for undesirable dimerization.Acknowledging the critical role of adsorbed hydrogen(H*)in HMF hydrogenation,a series of transition metal-doped dual-cubic Cu electrocatalysts(M-Cu,where M=Mo,Pd,Pt,Au,and Ag)were synthesized to systematically investigate the effect of varying H*reactivity on HMF hydrogenation,A pronounced correlation between DHMF selectivity and H*coverage was observed.Increasing H*coverage can enhance the selectivity for DHMF and prevent undesired dimerization of adsorbed HMF molecules.While elevated H*coverage enhanced DHMF selectivity,excessive coverage adversely impacted Faradaic efficiency due to competing hydrogen evolution reaction.This underscores the critical importance of finely tuning H*coverage.The optimal electrocatalyst,achieved by fine-tuning the doping amount of Pt on Cu,demonstrated a Faradaic efficiency of over 90%for DHMF in highconcentration HMF at-0.3 V,marking the highest record reported to date.
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the support of this work by the Fundamental Research Program of Shanxi Province(20210302123008,20210302124101)the Youth Innovation Promotion Association of CAS(2019178)+1 种基金the National Science Foundation for Excellent Young Scholars of China(21922815)the National Natural Science Foundation of China(21975275,22179139)。
文摘Hard carbons are widely investigated as potential anodes for lithium and sodium ion batteries owing to their internally well-tailored textures(closed pores and defects) and large microcrystalline interlayer spacing. The renewable biomass is a green and economically attractive carbon source to produce hard carbons. However, the chemical and structural complexity of biomass has plagued the understanding of evolution mechanism from organic precursors to hard carbons and the structure-property relationship.This makes it difficult to finely tune the microstructure of biomass-derived hard carbons, thus greatly restricting their high-performance applications. Most recently, the optimal utilization and controllable conversion of biomass-derived biopolymers(such as starch, cellulose and lignin) at the molecular level have become a burgeoning area of research to develop hard carbons for advanced batteries.Considering the principal source of carbonaceous materials is from biomass pyrolysis, we firstly overview the chemical structures and pyrolysis behaviors of three main biopolymers. Then, the controllable preparation of hard carbons using various physicochemical properties of biopolymers at the molecular level is systematically discussed. Furthermore, we highlight present challenges and further opportunities in this field. The Review will guide future research works on the design of sustainable hard carbons and the optimization of battery performance.
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 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supported by the Shuguang Program from Shanghai Education Development Foundation and Shanghai Municipal Education Commission(18SG035)State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua University(KF2015)。
文摘The exploration of advanced MoS_(2)-based electrode materials overcoming their inherent low conductivity and large volume changes is of importance for next-generation energy storage.In this work,we report a simple and high-efficient one-pot hydrothermal approach to prepare a unique and stable 1D/2D heterostructure.In the architecture,ultrathin carbon layer-coated MoS_(2) nanosheets with large expanded interlayer of 1.02 nm are vertically grown onto the Ti_(3)C_(2) MXene and cross-linked carbon nanotubes(CNTs),giving rise to a highly conductive 3D network.The interlayer expanded MoS_(2) nanosheets can greatly facilitate the Na ions/electrons transmission.Meanwhile,the N-doped 1D/2D CNTs-Ti_(3)C_(2) matrix can be used as a strong mechanical support to well relieve the large volume expansion upon cycles.As a combination result of several advantages,the developed quaternary C-MoS_(2)/CNTs-Ti_(3)C_(2) composite anode shows an excellent sodium storage performance(562 mA h g^(-1) at 100 mA g^(-1) after 200 cycles)and rate capability(475 mA h g^(-1) at 2000 mA g^(-1)).The density functional theory calculations further prove that the full combination of layer-expanded MoS_(2) nanosheets and N-doped Ti_(3)C_(2) matrix can significantly enhance the adsorption energy of Na ions,further resulting in the enhancement of sodium storage capabilities.
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 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.
