Cubic phase cobalt disulfide(CoS_(2))is recognized as a potential negative material for sodium-ion batteries(SIBs)because of its low band gap,simple synthesis process,and high capacity.Nonetheless,the challenges of sl...Cubic phase cobalt disulfide(CoS_(2))is recognized as a potential negative material for sodium-ion batteries(SIBs)because of its low band gap,simple synthesis process,and high capacity.Nonetheless,the challenges of slow ion diffusion and substantial volume change during cycling,resulting in inadequate rate and cycling performances,remain unresolved.Here,a porous structure is fabricated by etching electrospun carbon nanofibers,subsequently facilitating the growth of CoS_(2)nanoparticles at the pore locations.A nitrogen-doped carbon layer is then applied to the surface to buffer the volumetric expansion effect of CoS_(2).The findings indicate that the carbon nanofibers establish a stable conductive network,while the porous architecture of the carbon fibers,in conjunction with the carbon coating,efficiently mitigates volumetric expansion.Furthermore,density functional theory(DFT)studies show the presence of an interlayer van der Waals force between the sulfur atoms in CoS_(2)and the carbon atoms,which reduces the band gap,enhances the conductivity of the structure,and lowers the energy barrier of Na^(+)migration.The as-prepared anode achieves a reversible capacity of 302.6 mAh g^(-1)at 3.2 A g^(-1)and maintains a capacity of 384.6 mAh g^(-1)at 1.0 A g^(-1)over 800 cycles,demonstrating exceptional rate performance and improved cycling stability.This work shows that the combination of hierarchical porous architecture and a unique electronic structure offers valuable insights for designing high-performance negative materials for SIB s.展开更多
Direct seawater splitting has emerged as a popular and promising research direction for synthesising clean,green,non-polluting,and sustainable hydrogen energy without depending on high-purity water in the face of the ...Direct seawater splitting has emerged as a popular and promising research direction for synthesising clean,green,non-polluting,and sustainable hydrogen energy without depending on high-purity water in the face of the world’s shortage of fossil energy.However,efficient seawater splitting is hindered by slow kinetics caused by the ultra-low conductivity and the presence of bacteria,microorganisms,and stray ions in seawater.Additionally,producing hydrogen on an industrial scale is challenging due to the high production cost.The present review addresses these challenges from the catalyst point of view,namely,that designing catalysts with high catalytic activity and stability can directly affect the rate and effect of seawater splitting.From the ion transfer perspective,designing membranes can block harmful ions,improving the stability of seawater splitting.From the energy point of view,mixed seawater systems and self-powered systems also provide new and low-energy research systems for seawater splitting.Finally,ideas and directions for further research on direct seawater splitting in the future are pointed out,with the aim of achieving low-cost and high-efficiency hydrogen production.展开更多
Hydrazine-assisted water electrolysis presents a promising and efficient hydrogen production technology.However,developing high-performance hydrazine oxidation reaction(HzOR)and hydrogen evolution reaction(HER)bifunct...Hydrazine-assisted water electrolysis presents a promising and efficient hydrogen production technology.However,developing high-performance hydrazine oxidation reaction(HzOR)and hydrogen evolution reaction(HER)bifunctional catalysts remains challenging.Here,we report a bifunctional electrocatalyst of Ru NCs@NPC,embedding the ultrafine Ru nanoclusters into N-doped porous carbon via microwave reduction.Due to the ultrafine Ru nanoclusters and N doping,the composite exhibits exceptional activity for both HER and HzOR,requiring−55 and−67 mV to reach 10 mA·cm^(−2) in alkaline media.In the overall hydrazine splitting(OHzS)system,Ru NCs@NPC is used as both anode and cathode materials,achieving 10 mA·cm^(−2) only at 0.036 V.The zinc hydrazine(Zn-Hz)battery assembled with Ru NCs@NPC cathode and Zn foil anode can provide a stable voltage of 0.4 V and exhibit 98.5%energy efficiency.Therefore,integrating Zn-Hz battery with OHzS system enables self-powered H_(2) evolution.The density function theory calculations reveal that the Ru-N bond increases the metal-support interaction.展开更多
Developing efficient and stable catalysts for the hydrogen evolution reaction(HER)is essential for advancing anion-exchange membrane water electrolyzer(AEMWE)technology.In this study,we present a facile microwave redu...Developing efficient and stable catalysts for the hydrogen evolution reaction(HER)is essential for advancing anion-exchange membrane water electrolyzer(AEMWE)technology.In this study,we present a facile microwave reduction and low-temperature phosphorization strategy to synthesize a highly efficient HER catalyst,comprising P,N-codoped carbon-supported RuP_(2)nanocluster(RuP_(2)@PNC).RuP_(2)@PNC demonstrates outstanding HER performance,achieving overpotentials of 18 and 44 mV at a current density of 10 mA cm^(-2)in alkaline and acidic media,respectively.Furthermore,an AEMWE device utilizing RuP_(2)@PNC as the cathode catalyst delivers a current density of 0.5 A cm^(-2)at a cell voltage of 1.84 V and exhibits remarkable stability over 150 h of operation.Experimental analyses and density functional theory(DFT)calculations reveal that the synergistic effects of P,N-codoped and the unique structure of RuP_(2)enhance electron transfer between Ru and the support,optimize the electronic structure,and regulate the d–band center of Ru.These features improve water adsorption,weaken the Ru–H binding strength,and facilitate efficient H_(2)desorption,collectively driving the superior HER activity of RuP_(2)@PNC.This work offers an effective design strategy for high-performance HER catalysts and provides valuable insights for accelerating the development of AEMWE technology.展开更多
Zn-ion hybrid supercapacitors(ZHSCs),as emerging energy storage systems,combine high energy and power density with cost-effectiveness and safety,attracting significant attention.However,due to the inherent energy stor...Zn-ion hybrid supercapacitors(ZHSCs),as emerging energy storage systems,combine high energy and power density with cost-effectiveness and safety,attracting significant attention.However,due to the inherent energy storage mechanism and the diminishing marginal benefits of increased porosity on capacitance,engineering porous nanostructures to develop carbon materials with ideal architectures is crucial for achieving high performance.Herein,a novel web-in-web porous carbon/carbon nanotubes(CNTs)composite has been proposed,fabricated by a simple phase separation method and two-step carbonization.During pre-oxidation,gradual air oxidation induces the formation of an O,N co-doped polymer-chain template,which subsequently transforms into a graphitized web during high-temperature carbonization.The optimized web-in-web structure,enriched with abundant active sites,accelerates mass transport and charge transfer kinetics.When assembled in ZHSCs,the web-in-web cathode achieved a high area capacitance(14,309 mF cm^(-2))with high mass loading(38.2 mg cm^(-2)).It delivered excellent high-rate performance at 50 mA cm^(-2)with a capacitance retention of 83%after 10,000 cycles,also boosting a high energy density(1452.7μWh cm^(-2))and power density(30.8 mW cm^(-2)).Furthermore,ex situ characterization and in situ electrochemical analyses reveal hybrid energy storage mechanisms,involving both physical/chemical adsorption and precipitation/dissolution across different potential regions.This study provides a promising strategy for designing high-area-capacitance carbon cathodes boosting high-performance ZHSCs.展开更多
This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production fr...This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production from methanol aqueous solutions.The effectiveness of confining precipitation reactions within micellar cages was evaluated through extensive physicochemical cha racterization.In particula r,the nominal composition(0-5 mol%Fe)was preserved as ascertained by ICP-MS analysis,and the absence of separate iron-containing crystalline phases was supported by X-ray diffraction.The effective aliovalent doping and modulation of the optical properties were investigated using UV-Vis,Raman,and photoluminescence spectroscopies.2.5 mol%iron was found to be an optimal content to achieve a significant decrease in the band gap,enhance the concentration of oxygen vacancy defects,and increase the charge carrier lifetime.The photocatalytic activity of Fe-doped CeO_(2)prepared at different Fe contents with RM preparation was studied and compared with undoped CeO_(2).The optimal iron load was identified to be2.5 mol%,achieving the highest hydrogen production(7566μmol L-1after 240 min under visible light).Moreover,for comparison,the conventional precipitation(P)method was adopted to prepare iron containing CeO_(2)at the optimal content(2.5 mol%Fe).The Fe-doped CeO_(2)catalyst prepared by RM showed a significantly higher hydrogen production than that obtained with the sample prepared by the P method.The optimal Fe-doped CeO_(2),prepared by the RM method,was stable for six reuse cycles.Moreover,the role of water in the mechanism of photocatalytic hydrogen evolution under visible light was studied through the test in the presence of D2O.The obtained results evidenced that hydrogen was produced from the reduction of H^(+)by the electrons promoted in the conduction band,while methanol was preferentially oxidized by the photogenerated positive holes.展开更多
The prelithiated SiO_(x)anode showcases markedly improved Li-storage capabilities compared to its unlithiated counterparts,yet it faces hurdles such as slurry gassing,electrolyte deterioration,and capacity fade attrib...The prelithiated SiO_(x)anode showcases markedly improved Li-storage capabilities compared to its unlithiated counterparts,yet it faces hurdles such as slurry gassing,electrolyte deterioration,and capacity fade attributed to residual alkali and an unstable electrolyte/anode interface.To tackle these challenges,we propose a strategic utilization of residual alkali by creating an in-situ γ-LiAlO_(2)functional layer on the prelithiated SiO_(x)@C anode material.This is accomplished by incorporating a minor amount of Al_(2)O_(3)into the SiO_(x)@C/LiH precursor mixture before the solid-phase prelithiation process.The resulting modified prelithiated SiO_(x)@C anode with in-situ formed electrolyte-isolatingγ-LiAlO_(2)layer exhibits no discernible slurry gas generation within 7 days and substantially mitigates side reactions with the electrolyte,thereby boosting the initial coulombic efficiency and cycling stability of the SiO_(x)@C anode.In half-cell evaluations,the prelithiated SiO_(x)@C anode demonstrates a high Li-storage capacity of 1323 mAh g^(-1)and an impressive initial coulombic efficiency of 91.09%.When assessed in a 3.2 Ah 18,650 cylindrical battery,the prelithiated SiO_(x)@C anode showcases exceptional cyclability,retaining 81% of its capacity after 1000 cycles,underscoring its potential for practical applications.This study introduces a scalable and cost-effective prelithiation technique that propels the development and practical deployment of Si-based anodes by resolving persistent scientific challenges with the use of inexpensive additives.展开更多
The AZ31 Mg alloys were processed by 6% pre-compression and frustum shearing extrusion at various temperatures, and the microstructure, texture and mechanical properties of the resulting alloys are systematically inve...The AZ31 Mg alloys were processed by 6% pre-compression and frustum shearing extrusion at various temperatures, and the microstructure, texture and mechanical properties of the resulting alloys are systematically investigated. The results show that the grain size monotonically increases from 6.4 to 12.6 lm and the texture intensity increases from 6.7 to 9.6with the increase in the extrusion temperature. The combining effect of the pre-twinning and the frustum shearing deformation is found to contribute to the development of the weak basal texture in Mg alloys. The Mg alloy sheet produced at the extrusion temperature of 563 K exhibits excellent mechanical properties. The yield strength, ultimate tensile strength and elongation for the extruded alloys are 189.6 MPa, 288.4 MPa and 24.9%, respectively. Such improved mechanical properties are comparable or even superior to those of the alloys subjected to other deformation techniques, rendering the pre-compression and frustum shearing extrusion a promising way for further tailoring properties of Mg alloys.展开更多
As a two-dimensional(2D)material,graphene shows excellent advantages in the field of gas sensors due to its inherent large specific surface area and unique electrical properties.However,in the practical application of...As a two-dimensional(2D)material,graphene shows excellent advantages in the field of gas sensors due to its inherent large specific surface area and unique electrical properties.However,in the practical application of gas detection,graphene sheet is easy to form irreversible agglomeration and has some limitations such as low sensitivity,long response time and slow recovery speed,which greatly reduce its gas sensing performance.As a gas sensing material,three-dimensional(3D)porous graphene has been extensively studied in recent years owing to its larger specific surface area and stable structure.In order to synthesize graphene with different three-dimensional structures,many methods have been developed.Herein,the synthesis and assembly of three-dimensional graphene and its composites were reviewed,with emphasis on the application of three-dimensional graphene and its composites in the field of gas sensors.The challenges and development prospects of three-dimensional graphene materials in the application of gas sensors were briefly described.展开更多
We prepare a new type of patented biodegradable biomedical Mg-Nd-Zn-Zr(JDBM)alloy system and impose double continuously extrusion(DCE)processing.The lowest processing temperature is 250℃for JDBM-2.1Nd and 310℃for JD...We prepare a new type of patented biodegradable biomedical Mg-Nd-Zn-Zr(JDBM)alloy system and impose double continuously extrusion(DCE)processing.The lowest processing temperature is 250℃for JDBM-2.1Nd and 310℃for JDBM-2.8Nd,which increases with the Nd concentration.The highest yield strength of 541 MPa is achieved in JDBM-2.1 Nd samples when extruded at 250℃and the elongation is about 3.7%.Moreover,the alloy with a lower alloying element content can reach a higher yield strength while that with a higher alloying element content can reach a larger elongation after DCE processing.However,when extruded under the same conditions,the alloy with a higher alloying contents exhibits better tensile properties.展开更多
Transition metal sulfide(TMS)anodes exhibit the characteristics of phase stability and high capacity for lithium/sodium-ion batteries(LIBs/SIBs).However,the TMS anodes often suffer from poor electronic conductivity,lo...Transition metal sulfide(TMS)anodes exhibit the characteristics of phase stability and high capacity for lithium/sodium-ion batteries(LIBs/SIBs).However,the TMS anodes often suffer from poor electronic conductivity,low ionic diffusion and large volume expansion during Li/Na-ion intercalation significantly impairing the Li/Na-storage performance.Herein,a long chain heterostructure composed of the Co_(9)S_(8) and SnS are first reported,which can generate rich phase interfaces,and small crystal domains.The unique structure can facilitate the properties of reactivity,conductivity and ionic diffusion.In addition,the heterostructure surface is modified by the N-doped carbon(N-DC@(CoSn)S),successfully improving the structural stability.The synergistic effects of Co_(9)S_(8)/SnS heterostructure and coated carbon layer effectively increase the capacity and cycling stability.The N-DC@(CoSn)S anode delivers enhanced high specific capacities of 820.6 mAh·g^(−1) at 1.0 A·g^(–1) after 500 cycles for LIBs and 339.2 mAh·g^(–1)at 0.5 A·g^(–1) after 1000 cycles for SIBs,respectively.This work is expected to provide a material design idea for preparing LIBs/SIBs with high capacity and long cycling life.展开更多
This study explores how the chemical interaction between magnesium hydride(MgH_(2))and the additive CrO_(3) influences the hydrogen/lithium storage characteristics of MgH_(2).We have observed that a 5 wt.%CrO_(3) addi...This study explores how the chemical interaction between magnesium hydride(MgH_(2))and the additive CrO_(3) influences the hydrogen/lithium storage characteristics of MgH_(2).We have observed that a 5 wt.%CrO_(3) additive reduces the dehydrogenation activation energy of MgH_(2) by 68 kJ/mol and lowers the required dehydrogenation temperature by 80℃.CrO_(3) added MgH_(2) was also tested as an anode in an Li ion battery,and it is possible to deliver over 90%of the total theoretical capacity(2038 mAh/g).Evidence for improved reversibility in the battery reaction is found only after the incorporation of additives with MgH_(2).In depth characterization study by X-ray diffraction(XRD)technique provides convincing evidence that the CrO_(3) additive interacts with MgH_(2) and produces Cr/MgO byproducts.Gibbs free energy analyses confirm the thermodynamic feasibility of conversion from MgH_(2)/CrO_(3) to MgO/Cr,which is well supported by the identification of Cr(0)in the powder by X ray photoelectron spectroscopy(XPS)technique.Through high resolution transmission electron microscopy(HRTEM)and energy dispersive spectroscopy(EDS)we found evidence for the presence of 5 nm size Cr nanocrystals on the surface of MgO rock salt nanoparticles.There is also convincing ground to consider that MgO rock salt accommodates Cr in the lattice.These observations support the argument that creation of active metal–metal dissolved rock salt oxide interface may be vital for improving the reactivity of MgH_(2),both for the improved storage of hydrogen and lithium.展开更多
Water splitting has been proposed to be a promising approach to producing clean hydrogen fuel.The two half-reactions of water splitting,that is,the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),ta...Water splitting has been proposed to be a promising approach to producing clean hydrogen fuel.The two half-reactions of water splitting,that is,the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),take place kinetically fast in solutions with completely different pH values.Enabling HER and OER to simultaneously occur under kinetically favorable conditions while using exclusively low-cost,earth-abundant electrocatalysts is highly desirable but remains a challenge.Herein,we demonstrate that using a bipolar membrane(BPM)we can accomplish HER in a strongly acidic solution and OER in a strongly basic solution,with bifunctional self-supported cobaltnickel phosphide nanowire electrodes to catalyze both reactions.Such asymmetric acid/alkaline water electrolysis can be achieved at 1.567 V to deliver a current density of 10 mA/cm2 with ca.100%Faradaic efficiency.Moreover,using an“irregular”BPM with unintentional crossover the voltage needed to afford 10 mA/cm2 can be reduced to 0.847 V,due to the assistance of electrochemical neutralization between acid and alkaline.Furthermore,we show that BPM-based asymmetric water electrolysis can be accomplished in a circulated single-cell electrolyzer delivering 10 mA/cm2 at 1.550 V and splitting water very stably for at least 25 hours,and that water electrolysis is enabled by a solar panel operating at 0.908 V(@13 mA/cm2),using an“irregular”BPM.BPMbased asymmetric water electrolysis is a promising alternative to conventional proton and anion exchange membrane water electrolysis.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.52271211 and 52072120)the Science and Technology Innovation Program of Hunan Province,China(Nos.2022RC3037 and 2023RC3185)+1 种基金Hunan Provincial Natural Science Foundation Regional Joint Fund,China(No.2024JJ7205)the HORIZON-Marie Sklodowska-Curie Actions-2021-PF,European Union(No.101065098)
文摘Cubic phase cobalt disulfide(CoS_(2))is recognized as a potential negative material for sodium-ion batteries(SIBs)because of its low band gap,simple synthesis process,and high capacity.Nonetheless,the challenges of slow ion diffusion and substantial volume change during cycling,resulting in inadequate rate and cycling performances,remain unresolved.Here,a porous structure is fabricated by etching electrospun carbon nanofibers,subsequently facilitating the growth of CoS_(2)nanoparticles at the pore locations.A nitrogen-doped carbon layer is then applied to the surface to buffer the volumetric expansion effect of CoS_(2).The findings indicate that the carbon nanofibers establish a stable conductive network,while the porous architecture of the carbon fibers,in conjunction with the carbon coating,efficiently mitigates volumetric expansion.Furthermore,density functional theory(DFT)studies show the presence of an interlayer van der Waals force between the sulfur atoms in CoS_(2)and the carbon atoms,which reduces the band gap,enhances the conductivity of the structure,and lowers the energy barrier of Na^(+)migration.The as-prepared anode achieves a reversible capacity of 302.6 mAh g^(-1)at 3.2 A g^(-1)and maintains a capacity of 384.6 mAh g^(-1)at 1.0 A g^(-1)over 800 cycles,demonstrating exceptional rate performance and improved cycling stability.This work shows that the combination of hierarchical porous architecture and a unique electronic structure offers valuable insights for designing high-performance negative materials for SIB s.
基金support by National Key Research and Development Program of China(2022YFB3803502)National Natural Science Foundation of China(52103076)+5 种基金Science and Technology Commission of Shanghai Municipality(23ZR1400300)special fund of Beijing Key Laboratory of Indoor Air Quality Evaluat ion and Control(NO.BZ0344KF21-02)State Key Laboratory of Electrical Insulation and Power Equipment(EIPE22203)JLF is a member of LSRE-LCM–Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and Materials,supported by national funds through FCT/MCTES(PIDDAC):LSRE-LCM,UIDB/50020/2020(DOI:10.54499/UIDB/50020/2020)UIDP/50020/2020(DOI:10.54499/UIDP/50020/2020)ALiCE,LA/P/0045/2020(DOI:10.54499/LA/P/0045/2020).
文摘Direct seawater splitting has emerged as a popular and promising research direction for synthesising clean,green,non-polluting,and sustainable hydrogen energy without depending on high-purity water in the face of the world’s shortage of fossil energy.However,efficient seawater splitting is hindered by slow kinetics caused by the ultra-low conductivity and the presence of bacteria,microorganisms,and stray ions in seawater.Additionally,producing hydrogen on an industrial scale is challenging due to the high production cost.The present review addresses these challenges from the catalyst point of view,namely,that designing catalysts with high catalytic activity and stability can directly affect the rate and effect of seawater splitting.From the ion transfer perspective,designing membranes can block harmful ions,improving the stability of seawater splitting.From the energy point of view,mixed seawater systems and self-powered systems also provide new and low-energy research systems for seawater splitting.Finally,ideas and directions for further research on direct seawater splitting in the future are pointed out,with the aim of achieving low-cost and high-efficiency hydrogen production.
基金supported by the National Natural Science Foundation of China(Nos.52371222 and 52271211)the Natural Science Foundation of Hunan Province in China(Nos.2024JJ4022,2023JJ30277 and 2023JJ50043)+1 种基金the Science and Technology Innovation Program of Hunan Province(No.2023RC3185),ChinaHORIZON-Marie Skłodowska-Curie Actions-2021-PF(No.101065098),European Union.
文摘Hydrazine-assisted water electrolysis presents a promising and efficient hydrogen production technology.However,developing high-performance hydrazine oxidation reaction(HzOR)and hydrogen evolution reaction(HER)bifunctional catalysts remains challenging.Here,we report a bifunctional electrocatalyst of Ru NCs@NPC,embedding the ultrafine Ru nanoclusters into N-doped porous carbon via microwave reduction.Due to the ultrafine Ru nanoclusters and N doping,the composite exhibits exceptional activity for both HER and HzOR,requiring−55 and−67 mV to reach 10 mA·cm^(−2) in alkaline media.In the overall hydrazine splitting(OHzS)system,Ru NCs@NPC is used as both anode and cathode materials,achieving 10 mA·cm^(−2) only at 0.036 V.The zinc hydrazine(Zn-Hz)battery assembled with Ru NCs@NPC cathode and Zn foil anode can provide a stable voltage of 0.4 V and exhibit 98.5%energy efficiency.Therefore,integrating Zn-Hz battery with OHzS system enables self-powered H_(2) evolution.The density function theory calculations reveal that the Ru-N bond increases the metal-support interaction.
基金supported by the National Natural Science Foundation of China(Nos.52371222 and 52271211)the Natural Science Foundation of Hunan Province in China(Nos.2025JJ60350,2024JJ4022,and 2023JJ30277)+1 种基金the Key Research and Development Program of Hunan Province(No.2023GK2035)HORIZON–Marie Sk?odowska–Curie Actions–2021–PF(No.101065098),European Union
文摘Developing efficient and stable catalysts for the hydrogen evolution reaction(HER)is essential for advancing anion-exchange membrane water electrolyzer(AEMWE)technology.In this study,we present a facile microwave reduction and low-temperature phosphorization strategy to synthesize a highly efficient HER catalyst,comprising P,N-codoped carbon-supported RuP_(2)nanocluster(RuP_(2)@PNC).RuP_(2)@PNC demonstrates outstanding HER performance,achieving overpotentials of 18 and 44 mV at a current density of 10 mA cm^(-2)in alkaline and acidic media,respectively.Furthermore,an AEMWE device utilizing RuP_(2)@PNC as the cathode catalyst delivers a current density of 0.5 A cm^(-2)at a cell voltage of 1.84 V and exhibits remarkable stability over 150 h of operation.Experimental analyses and density functional theory(DFT)calculations reveal that the synergistic effects of P,N-codoped and the unique structure of RuP_(2)enhance electron transfer between Ru and the support,optimize the electronic structure,and regulate the d–band center of Ru.These features improve water adsorption,weaken the Ru–H binding strength,and facilitate efficient H_(2)desorption,collectively driving the superior HER activity of RuP_(2)@PNC.This work offers an effective design strategy for high-performance HER catalysts and provides valuable insights for accelerating the development of AEMWE technology.
基金financially supported by the National Key Research and Development Program of China(No.2024YFA1210602)Guangdong Basic and Applied Basic Research Foundation(No.2023A1515140044)
文摘Zn-ion hybrid supercapacitors(ZHSCs),as emerging energy storage systems,combine high energy and power density with cost-effectiveness and safety,attracting significant attention.However,due to the inherent energy storage mechanism and the diminishing marginal benefits of increased porosity on capacitance,engineering porous nanostructures to develop carbon materials with ideal architectures is crucial for achieving high performance.Herein,a novel web-in-web porous carbon/carbon nanotubes(CNTs)composite has been proposed,fabricated by a simple phase separation method and two-step carbonization.During pre-oxidation,gradual air oxidation induces the formation of an O,N co-doped polymer-chain template,which subsequently transforms into a graphitized web during high-temperature carbonization.The optimized web-in-web structure,enriched with abundant active sites,accelerates mass transport and charge transfer kinetics.When assembled in ZHSCs,the web-in-web cathode achieved a high area capacitance(14,309 mF cm^(-2))with high mass loading(38.2 mg cm^(-2)).It delivered excellent high-rate performance at 50 mA cm^(-2)with a capacitance retention of 83%after 10,000 cycles,also boosting a high energy density(1452.7μWh cm^(-2))and power density(30.8 mW cm^(-2)).Furthermore,ex situ characterization and in situ electrochemical analyses reveal hybrid energy storage mechanisms,involving both physical/chemical adsorption and precipitation/dissolution across different potential regions.This study provides a promising strategy for designing high-area-capacitance carbon cathodes boosting high-performance ZHSCs.
基金funding from the"Ministero dell'Universitàe della Ricerca(MUR)"(Italy)under the"Dipartimento di Eccellenza 2018-2022"program.
文摘This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production from methanol aqueous solutions.The effectiveness of confining precipitation reactions within micellar cages was evaluated through extensive physicochemical cha racterization.In particula r,the nominal composition(0-5 mol%Fe)was preserved as ascertained by ICP-MS analysis,and the absence of separate iron-containing crystalline phases was supported by X-ray diffraction.The effective aliovalent doping and modulation of the optical properties were investigated using UV-Vis,Raman,and photoluminescence spectroscopies.2.5 mol%iron was found to be an optimal content to achieve a significant decrease in the band gap,enhance the concentration of oxygen vacancy defects,and increase the charge carrier lifetime.The photocatalytic activity of Fe-doped CeO_(2)prepared at different Fe contents with RM preparation was studied and compared with undoped CeO_(2).The optimal iron load was identified to be2.5 mol%,achieving the highest hydrogen production(7566μmol L-1after 240 min under visible light).Moreover,for comparison,the conventional precipitation(P)method was adopted to prepare iron containing CeO_(2)at the optimal content(2.5 mol%Fe).The Fe-doped CeO_(2)catalyst prepared by RM showed a significantly higher hydrogen production than that obtained with the sample prepared by the P method.The optimal Fe-doped CeO_(2),prepared by the RM method,was stable for six reuse cycles.Moreover,the role of water in the mechanism of photocatalytic hydrogen evolution under visible light was studied through the test in the presence of D2O.The obtained results evidenced that hydrogen was produced from the reduction of H^(+)by the electrons promoted in the conduction band,while methanol was preferentially oxidized by the photogenerated positive holes.
基金supported by the National Natural Science Foundation of China(52234001,52201254)the Science and Technology Planning Project of Hunan Province(2018TP1017)+3 种基金the Science,Technoloy and Innovation Project of Changsha Research Institute of Mining and Metallurgy(22-C5CL001)the Young Student Fundamental Research Project of Hunan Natural Science Foundation(2024JJ10036)the Introducing Major Universities and Research Institutions to Jointly Build Innovative Carrier Project of Jining City(2023DYDS022)the Scientific Research Foundation for New Talents in University of Jinan(XRC2406)。
文摘The prelithiated SiO_(x)anode showcases markedly improved Li-storage capabilities compared to its unlithiated counterparts,yet it faces hurdles such as slurry gassing,electrolyte deterioration,and capacity fade attributed to residual alkali and an unstable electrolyte/anode interface.To tackle these challenges,we propose a strategic utilization of residual alkali by creating an in-situ γ-LiAlO_(2)functional layer on the prelithiated SiO_(x)@C anode material.This is accomplished by incorporating a minor amount of Al_(2)O_(3)into the SiO_(x)@C/LiH precursor mixture before the solid-phase prelithiation process.The resulting modified prelithiated SiO_(x)@C anode with in-situ formed electrolyte-isolatingγ-LiAlO_(2)layer exhibits no discernible slurry gas generation within 7 days and substantially mitigates side reactions with the electrolyte,thereby boosting the initial coulombic efficiency and cycling stability of the SiO_(x)@C anode.In half-cell evaluations,the prelithiated SiO_(x)@C anode demonstrates a high Li-storage capacity of 1323 mAh g^(-1)and an impressive initial coulombic efficiency of 91.09%.When assessed in a 3.2 Ah 18,650 cylindrical battery,the prelithiated SiO_(x)@C anode showcases exceptional cyclability,retaining 81% of its capacity after 1000 cycles,underscoring its potential for practical applications.This study introduces a scalable and cost-effective prelithiation technique that propels the development and practical deployment of Si-based anodes by resolving persistent scientific challenges with the use of inexpensive additives.
基金The National Natural Science Foundation of China(No.61302167)the Key Science and Technology Research Projects of Henan Province(No.172102210390)the Scientific Research Starting Foundation for High Level Talents in Jinling Institute of Technology(No.jit-rcyj-201602)
基金partly supported by the National Natural Science Foundation of China(Grant Nos.51505143 and51704112)the Scientific Research Fund of Hunan Provincial Education Department(Grant No.17B089)the financial supports from the China Postdoctoral Science Foundation(Grant No.2016T90759)
文摘The AZ31 Mg alloys were processed by 6% pre-compression and frustum shearing extrusion at various temperatures, and the microstructure, texture and mechanical properties of the resulting alloys are systematically investigated. The results show that the grain size monotonically increases from 6.4 to 12.6 lm and the texture intensity increases from 6.7 to 9.6with the increase in the extrusion temperature. The combining effect of the pre-twinning and the frustum shearing deformation is found to contribute to the development of the weak basal texture in Mg alloys. The Mg alloy sheet produced at the extrusion temperature of 563 K exhibits excellent mechanical properties. The yield strength, ultimate tensile strength and elongation for the extruded alloys are 189.6 MPa, 288.4 MPa and 24.9%, respectively. Such improved mechanical properties are comparable or even superior to those of the alloys subjected to other deformation techniques, rendering the pre-compression and frustum shearing extrusion a promising way for further tailoring properties of Mg alloys.
基金financially supported by the Graduate Scientific Research and Innovation Foundation of Chongqing,China(No.CYS20001)。
文摘As a two-dimensional(2D)material,graphene shows excellent advantages in the field of gas sensors due to its inherent large specific surface area and unique electrical properties.However,in the practical application of gas detection,graphene sheet is easy to form irreversible agglomeration and has some limitations such as low sensitivity,long response time and slow recovery speed,which greatly reduce its gas sensing performance.As a gas sensing material,three-dimensional(3D)porous graphene has been extensively studied in recent years owing to its larger specific surface area and stable structure.In order to synthesize graphene with different three-dimensional structures,many methods have been developed.Herein,the synthesis and assembly of three-dimensional graphene and its composites were reviewed,with emphasis on the application of three-dimensional graphene and its composites in the field of gas sensors.The challenges and development prospects of three-dimensional graphene materials in the application of gas sensors were briefly described.
基金support by the national key research and development plan(No.2016YFC1102100)the National Natural Science Founda-tion of China(Nos.51501110,51728202,11332013 and 51501115)+1 种基金the Natural Science Foundation of Shang-hai(15ZR1422600)the Shanghai Jiao Tong University Medical-engineering Cross Fund(No.YG2015MS66 and No.YG2014MS62).
文摘We prepare a new type of patented biodegradable biomedical Mg-Nd-Zn-Zr(JDBM)alloy system and impose double continuously extrusion(DCE)processing.The lowest processing temperature is 250℃for JDBM-2.1Nd and 310℃for JDBM-2.8Nd,which increases with the Nd concentration.The highest yield strength of 541 MPa is achieved in JDBM-2.1 Nd samples when extruded at 250℃and the elongation is about 3.7%.Moreover,the alloy with a lower alloying element content can reach a higher yield strength while that with a higher alloying element content can reach a larger elongation after DCE processing.However,when extruded under the same conditions,the alloy with a higher alloying contents exhibits better tensile properties.
基金This study was financially supported by the National Natural Science Foundation of China(Nos.52271211 and 52171207)the HORIZON-Marie Skłodowska-Curie Actions-2021-PF(No.101065098)+2 种基金Hunan Provincial Natural Science Foundation of China(No.2022JJ40162)the Scientific Research Fund of Hunan Provincial Education Department(No.21B0406)the science and technology innovation Program of Hunan Province(No.2022RC3037).
文摘Transition metal sulfide(TMS)anodes exhibit the characteristics of phase stability and high capacity for lithium/sodium-ion batteries(LIBs/SIBs).However,the TMS anodes often suffer from poor electronic conductivity,low ionic diffusion and large volume expansion during Li/Na-ion intercalation significantly impairing the Li/Na-storage performance.Herein,a long chain heterostructure composed of the Co_(9)S_(8) and SnS are first reported,which can generate rich phase interfaces,and small crystal domains.The unique structure can facilitate the properties of reactivity,conductivity and ionic diffusion.In addition,the heterostructure surface is modified by the N-doped carbon(N-DC@(CoSn)S),successfully improving the structural stability.The synergistic effects of Co_(9)S_(8)/SnS heterostructure and coated carbon layer effectively increase the capacity and cycling stability.The N-DC@(CoSn)S anode delivers enhanced high specific capacities of 820.6 mAh·g^(−1) at 1.0 A·g^(–1) after 500 cycles for LIBs and 339.2 mAh·g^(–1)at 0.5 A·g^(–1) after 1000 cycles for SIBs,respectively.This work is expected to provide a material design idea for preparing LIBs/SIBs with high capacity and long cycling life.
基金supported by the projects UIDB/00481/2020 and UIDP/00481/2020-Fundação para a Ciência e a Tecnologia,DOI 10.54499/UIDB/00481/2020(https://doi.org/10.54499/UIDB/00481/2020)and DOI 10.54499/UIDP/00481/2020(https://doi.org/10.54499/UIDP/00481/2020)supported by CENTRO-01-0145-FEDER-022083-Centro Portugal Regional Operational Programme(Centro 2020),under the PORTUGAL 2020 Partnership Agreement,through the European Regional Development Fund(ERDF).This article is a result of the Innovation Pact“NGS-New Generation Storage”(C644936001-00000045)+3 种基金by“NGS”Consortium,co-financed by NextGeneration EU,through the Incentive System“Agendas para a Inovação Empresarial”(“Agendas for Business Innovation”)within the Recovery and Resilience Plan(PRR).D.P acknowledges FCT,Portugal for the financial support with reference CEECIND/04158/2017(https://doi.org/10.54499/CEECIND/04158/2017/CP1459/CT0029)funding from the SMART-ER project,funded by the European Union’s Horizon 2020 research and innovation programme under Grant Agreement#101016888.support granted by the Recovery and Resilience Plan(PRR)and by the Next Generation EU European Funds to Universidade de Aveiro,through the Agenda for Business Innovation“NGS-Next Generation Storage”(Project no 02/C05-i01.01/2022 with the application C644936001-00000045).
文摘This study explores how the chemical interaction between magnesium hydride(MgH_(2))and the additive CrO_(3) influences the hydrogen/lithium storage characteristics of MgH_(2).We have observed that a 5 wt.%CrO_(3) additive reduces the dehydrogenation activation energy of MgH_(2) by 68 kJ/mol and lowers the required dehydrogenation temperature by 80℃.CrO_(3) added MgH_(2) was also tested as an anode in an Li ion battery,and it is possible to deliver over 90%of the total theoretical capacity(2038 mAh/g).Evidence for improved reversibility in the battery reaction is found only after the incorporation of additives with MgH_(2).In depth characterization study by X-ray diffraction(XRD)technique provides convincing evidence that the CrO_(3) additive interacts with MgH_(2) and produces Cr/MgO byproducts.Gibbs free energy analyses confirm the thermodynamic feasibility of conversion from MgH_(2)/CrO_(3) to MgO/Cr,which is well supported by the identification of Cr(0)in the powder by X ray photoelectron spectroscopy(XPS)technique.Through high resolution transmission electron microscopy(HRTEM)and energy dispersive spectroscopy(EDS)we found evidence for the presence of 5 nm size Cr nanocrystals on the surface of MgO rock salt nanoparticles.There is also convincing ground to consider that MgO rock salt accommodates Cr in the lattice.These observations support the argument that creation of active metal–metal dissolved rock salt oxide interface may be vital for improving the reactivity of MgH_(2),both for the improved storage of hydrogen and lithium.
基金This study was financially supported by the European Horizon 2020 project“CritCat”under the grant agreement number 686053Lifeng Liu acknowledges the financial support from the Portuguese Foundation of Science and Technology(FCT)under the projects“IF/2014/01595”and“IF/01595/2014/CP1247/CT0001.”+1 种基金Isilda Amorim is thankful for the support to FCT PhD grant SFRH/BD/137546/2018Zhipeng Yu acknowledges the support of the China Scholarship Council(Grant no.201806150015).
文摘Water splitting has been proposed to be a promising approach to producing clean hydrogen fuel.The two half-reactions of water splitting,that is,the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),take place kinetically fast in solutions with completely different pH values.Enabling HER and OER to simultaneously occur under kinetically favorable conditions while using exclusively low-cost,earth-abundant electrocatalysts is highly desirable but remains a challenge.Herein,we demonstrate that using a bipolar membrane(BPM)we can accomplish HER in a strongly acidic solution and OER in a strongly basic solution,with bifunctional self-supported cobaltnickel phosphide nanowire electrodes to catalyze both reactions.Such asymmetric acid/alkaline water electrolysis can be achieved at 1.567 V to deliver a current density of 10 mA/cm2 with ca.100%Faradaic efficiency.Moreover,using an“irregular”BPM with unintentional crossover the voltage needed to afford 10 mA/cm2 can be reduced to 0.847 V,due to the assistance of electrochemical neutralization between acid and alkaline.Furthermore,we show that BPM-based asymmetric water electrolysis can be accomplished in a circulated single-cell electrolyzer delivering 10 mA/cm2 at 1.550 V and splitting water very stably for at least 25 hours,and that water electrolysis is enabled by a solar panel operating at 0.908 V(@13 mA/cm2),using an“irregular”BPM.BPMbased asymmetric water electrolysis is a promising alternative to conventional proton and anion exchange membrane water electrolysis.
