Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ...Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects.展开更多
Graphdiyne(GDY)is a two-dimensional carbon allotrope with exceptional physical and chemical properties that is gaining increasing attention.However,its efficient and scalable synthesis remains a significant challenge....Graphdiyne(GDY)is a two-dimensional carbon allotrope with exceptional physical and chemical properties that is gaining increasing attention.However,its efficient and scalable synthesis remains a significant challenge.We present a microwave-assisted approach for its continuous,large-scale production which enables synthesis at a rate of 0.6 g/h,with a yield of up to 90%.The synthesized GDY nanosheets have an average diameter of 246 nm and a thickness of 4 nm.We used GDY as a stable coating for potassium(K)metal anodes(K@GDY),taking advantage of its unique molecular structure to provide favorable paths for K-ion transport.This modification significantly inhibited dendrite formation and improved the cycling stability of K metal batteries.Full-cells with perylene-3,4,9,10-tetracarboxylic dianhydride(PTCDA)cathodes showed the clear superiority of the K@GDY anodes over bare K anodes in terms of performance,stability,and cycle life.The K@GDY maintained a stable voltage plateau and gave an excellent capacity retention after 600 cycles with nearly 100%Coulombic efficiency.This work not only provides a scalable and efficient way for GDY synthesis but also opens new possibilities for its use in energy storage and other advanced technologies.展开更多
To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bisp...To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bispyridylanthrahydrazone(9,10‑PAH)were designed and synthesized.Utilizing 9‑PAH and 9,10‑PAH as promising anticancer ligands,their respective copper complexes,namely[Cu(L1)Cl_(2)]Cl(1)and{[Cu_(4)(μ_(2)‑Cl)_(3)Cl_(4)(9,10‑PAH)_(2)(DMSO)_(2)]Cl_(2)}_(n)(2),were subsequently synthesized,where the new ligand L1 is formed by coupling two 9‑PAH ligands in the coordination reaction.The chemical and crystal structures of 1 and 2 were elucidated by IR,MS,elemental analysis,and single‑crystal X‑ray diffraction.Complex 1 forms a mononuclear structure.L1 coordinates with Cu through its three N atoms,together with two Cl atoms,to form a five‑coordinated square pyramidal geometry.Complex 2 constitutes a polymeric structure,wherein each structural unit centrosymmetrically encompasses two five‑coordinated binuclear copper complexes(Cu1,Cu2)of 9,10‑PAH,with similar square pyramidal geometry.A chlorine atom(Cl_(2)),located at the symmetry center,bridges Cu1 and Cu1A to connect the two binuclear copper structures.Meanwhile,the two five‑coordinated Cu2 atoms symmetrically bridge the adjacent structural units via one coordinated Cl atom,respectively,thus forming a 1D chain‑like polymeric structure.In vitro anticancer activity assessments revealed that 1 and 2 showed significant cytotoxicity even higher than cisplatin.Specifically,the IC_(50)values of 2 against HeLa‑229 and SK‑OV‑3 cancer cell lines were determined to be(5.92±0.32)μmol·L^(-1)and(6.48±0.39)μmol·L^(-1),respectively.2 could also block the proliferation of HeLa‑229 cells in S phase and significantly induce cell apoptosis.In addition,fluorescence quenching competition experiments suggested that 2 might interact with DNA by an intercalative binding mode,offering insights into its underlying anticancer mechanism.CCDC:2388918,1;2388919,2.展开更多
Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remedi...Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remediation of heavy metals in agricultural soils are crucial.These two aspects support each other,forming a close and complete decisionmaking chain.Therefore,this review systematically summarizes the distribution characteristics of soil heavy metal pollution,the correlation between soil and crop heavy metal contents,the presence pattern and migration and transformation mode of heavy metals in the soil-crop system.The advantages and disadvantages of the risk evaluation tools and models of heavy metal pollution in farmland are further outlined,which provides important guidance for an in-depth understanding of the characteristics of heavymetal pollution in farmland soils and the assessment of the environmental risk.Soil remediation strategies involve multiple physical,chemical,biological and even combined technologies,and this paper compares the potential and effect of the above current remediation technologies in heavy metal polluted farmland soils.Finally,the main problems and possible research directions of future heavy metal risk assessment and remediation technologies in agricultural soils are prospected.This review provides new ideas for effective assessment and selection of remediation technologies based on the characterization of soil heavy metals.展开更多
AgVO_(3)/ZIF-8 composites with enhanced photocatalytic effect were prepared by the combination of AgVO_(3)and ZIF-8.X-ray diffraction(XRD),scanning electron microscopy(SEM),high-power transmission electron microscopy(...AgVO_(3)/ZIF-8 composites with enhanced photocatalytic effect were prepared by the combination of AgVO_(3)and ZIF-8.X-ray diffraction(XRD),scanning electron microscopy(SEM),high-power transmission electron microscopy(HRTEM),X-ray photoelectron spectroscopy(XPS),ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS),photoluminescence(PL)spectroscopy,electron spin resonance(ESR)spectroscopy,transient photocurrent and electrochemical impedance spectroscopy(EIS)were used to characterize binary composites.Tetracycline(TC)was used as a substrate to study the performance efficiency of the degradation of photocatalysts under light conditions,and the degradation effect of TC was also evaluated under different mass concentrations and ionic contents.In addition,we further investigated the photocatalytic mechanism of the binary composite material AgVO_(3)/ZIF-8 and identified the key active components responsible for the catalytic degradation of this new photocatalyst.The experimental results show that the degradation efficiency of 10%-AZ,prepared with a molar ratio of 10%AgVO_(3)and ZIF-8 to TC,was 75.0%.This indicates that the photocatalytic activity can be maintained even under a certain ionic content,making it a suitable photocatalyst for optimal use.In addition,the photocatalytic mechanism of binary composites was further studied by the active species trapping experiment.展开更多
Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nano...Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nanorods,which had many voids.The S-FeCoTA catalysts exhibited excellent electrochemical oxygen evolution reaction(OER)performance with a low overpotential of 273 mV at 10 mA·cm^(-2)and a small Tafel slope of 36 mV·dec^(-1)in 1 mol·L^(-1)KOH.The potential remained at 1.48 V(vs RHE)at 10 mA·cm^(-2)under continuous testing for 15 h,implying that S-FeCoTA had good stability.The Faraday efficiency of S-FeCoTA was 94%.The outstanding OER activity of S-FeCoTA is attributed to the synergistic effects among S,Fe,and Co,thus promoting electron transfer,reducing the reaction kinetic barrier,and enhancing the OER performance.展开更多
(2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under...(2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under solvothermal conditions,to react with transition metals achieving four novel metal-organic frameworks(MOFs):[Zn(IP)(L_(1))]_(n)(1),{[Cd(IP)(L_(1))]·H_(2)O}_(n)(2),{[Co(IP)(L_(1))]·H_(2)O}_(n)(3),and[Zn(IP)(L_(2))(H_(2)O)]_(n)(4).MOFs 1-4 have been characterized by single-crystal X-ray diffraction,powder X-ray diffraction,thermogravimetry,and elemental analysis.Single-crystal X-ray diffraction shows that MOF 1 crystallizes in the monoclinic crystal system with space group P2_(1)/n,and MOFs 2-4 belong to the triclinic system with the P1 space group.1-3 are 2D sheet structures,2 and 3 have similar structural characters,whereas 4 is a 1D chain structure.Furthermore,1-3 exhibited certain photocatalytic capability in the degradation of rhodamine B(Rh B)and pararosaniline hydrochloride(PH).4could be used as a heterogeneous catalyst for the Knoevenagel reaction starting with benzaldehyde derivative and malononitrile.4 could promote the reaction to achieve corresponding products in moderate yields within 3 h.Moreover,the catalyst exhibited recyclability for up to three cycles without significantly dropping its activity.A mechanism for MOF 4 catalyzed Knoevenagel condensation reaction of aromatic aldehyde and malononitrile has been initially proposed.CCDC:2356488,1;2356497,2;2356499,3;2356498,4.展开更多
Lithium-ion batteries(LIBs)are the most popular energy storage devices due to their high energy density,high operating voltage,and long cycle life.However,green and effective recycling methods are needed because LIBs ...Lithium-ion batteries(LIBs)are the most popular energy storage devices due to their high energy density,high operating voltage,and long cycle life.However,green and effective recycling methods are needed because LIBs contain heavy metals such as Co,Ni,and Mn and organic compounds inside,which seriously threaten human health and the environment.In this work,we review the current status of spent LIB recycling,discuss the traditional pyrometallurgical and hydrometallurgical recovery processes,and summarize the existing short-process recovery technologies such as salt-assisted roasting,flotation processes,and direct recycling.Finally,we analyze the problems and potential research prospects of the current recycling process,and point out that the multidisciplinary integration of recycling will become the mainstream technology for the development of spent LIBs.展开更多
Metal-iodine batteries have attracted widespread attention due to their long cycle life,high energy density,remarkable charging capability and low self-discharge rate.Nevertheless,this development is hampered by the c...Metal-iodine batteries have attracted widespread attention due to their long cycle life,high energy density,remarkable charging capability and low self-discharge rate.Nevertheless,this development is hampered by the challenges of the iodine cathode and metal anode,including the hydrogen evolution reaction(HER),sluggish kinetics,shuttle effect of polyiodine ion at the cathode and dendrite formation,corrosion and passivation at the anode.This review summarizes recent developments in metaliodine batteries,including zinc-iodine batteries,lithiumiodine batteries,sodium-iodine batteries,etc.The challenges in the cathode,anode,electrolyte and separator of metal-iodine batteries are discussed,along with the corresponding design and synthesis strategies and specific methods to improve the electrochemical performance.Selecting appropriate cathode hosts,constructing surface protective layers,adding anode additives,making threedimensional anode designs and employing better electrolytes and functional separators to obstruct the production and shuttling of polyiodine ions are highlighted.Finally,future guidelines and directions for the development of metal-iodine batteries are proposed.展开更多
Reasonable manipulation of component and microstructure is considered as a potential route to realize high-performance microwave absorber.In this paper,micro-sized hexapod-like CuS/Cu_(9)S_(5) composites were synthesi...Reasonable manipulation of component and microstructure is considered as a potential route to realize high-performance microwave absorber.In this paper,micro-sized hexapod-like CuS/Cu_(9)S_(5) composites were synthesized via a facile approach involving the solvothermal method and subsequent sulfuration treatment.The resultant CuS/Cu_(9)S_(5) exhibited superb microwave absorbing capacity with a minimum reflection loss(RLmin)of-59.38 dB at 2.7 mm.The maximum effective absorption bandwidth(EABmax)was 7.44 GHz(10.56-18 GHz)when the thickness was reduced to 2.3 mm.The outstanding microwave absorbing ability of CuS/Cu_(9)S_(5) composites is mainly related to its unique hexapod shape and the formation of heterogeneous interfaces.The unique hexapod shape significantly promotes the multi-reflection of the incident electromagnetic wave(EMW)increasing the attenuation path of EMWs in the material.Hetero-geneous interfaces between CuS/Cu_(9)S_(5) enable powerful interface polarization,contributing to the atten-uation of EMWs propagating in the medium.In addition,the EMW absorption performance of CuS/Cu_(9)S_(5) composites is also inseparable from the conduction loss.This study provides a strong reference for the research of EMW absorbent materials based on transition metal sulfides.展开更多
High-entropy alloy(HEA)nanoparticles(NPs)have attracted great attention in electrocatalysis due to their tailorable complex compositions and unique properties.Herein,we introduce Fe,Co,Ni,Cr and Mn into the metal-poly...High-entropy alloy(HEA)nanoparticles(NPs)have attracted great attention in electrocatalysis due to their tailorable complex compositions and unique properties.Herein,we introduce Fe,Co,Ni,Cr and Mn into the metal-polyphenol coordination system to prepare HEA NPs enclosed in N-doped carbon(FeCoNiCrMn)with great potential for catalyzing oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).The unique high-entropy structural characteristics in FeCoNiCrMn facilitate effective interplay between metal species,leading to improved ORR(E_(1/2)=0.89 V)and OER(η=330 mV,j=10 mA·cm^(−2))activity.Additionally,FeCoNiCrMn exhibits excellent open-circuit voltage(1.523 V),power density(110 mW·cm^(−2))and long-term durability,outperforming Pt/C+IrO_(2) electrodes as a cathode catalyst in Zn-air batteries(ZABs).Such polyphenol-assisted alloying method broadens and simplifies the development of HEA electrocatalysts for high-performance ZABs.展开更多
Liquid metals(LMs),because of their ability to remain in a liquid state at room temperature,render them highly versatile for applications in electronics,energy storage,medicine,and robotics.Among various LMs,Ga-based ...Liquid metals(LMs),because of their ability to remain in a liquid state at room temperature,render them highly versatile for applications in electronics,energy storage,medicine,and robotics.Among various LMs,Ga-based LMs exhibit minimal cytotoxicity,low viscosity,high thermal and electrical conductivities,and excellent wettability.Therefore,Ga-based LM composites(LMCs)have emerged as a recent research focus.Recent advancements have focused on novel fabrication techniques and applications spanning energy storage,flexible electronics,and biomedical devices.Particularly noteworthy are the developments in wearable sensors and electronic skins,which hold promise for healthcare monitoring and human-machine interfaces.Despite their potential,challenges,such as oxidative susceptibil-ity and biocompatibility,remain.Creating bio-based LMC materials is a promising approach to address these issues while exploring new avenues to optimize LMC performance and broaden its application domains.This review provides a concise overview of the recent trends in LMC research,highlights their transformative impacts,and outlines key directions for future investigation and development.展开更多
In recent years,renewable energy sources,which aim to replace rapidly depleting fossil fuels,face challenges due to limited energy storage and conversion technologies.To enhance energy storage and conversion efficienc...In recent years,renewable energy sources,which aim to replace rapidly depleting fossil fuels,face challenges due to limited energy storage and conversion technologies.To enhance energy storage and conversion efficiency,extensive research has been conducted in the academic community on numerous potential materials.Among these materials,metal fluorides have attracted significant attention due to their ionic metal-fluorine bonds and tunable electronic structures,attributed to the highest electronegativity of fluorine in their chemical composition.This makes them promising candidates for future electrochemical applications in various fields.However,metal fluorides encounter various challenges in different application directions.Therefore,we comprehensively review the applications of metal fluorides in the field of energy storage and conversion,aiming to deepen our understanding of their exhibited characteristics in different electrochemical processes.In this paper,we summarize the difficulties and improvement methods encountered in different types of battery applications and several typical electrode optimization strategies in the field of supercapacitors.In the field of water electrolysis,we focus on surface reconstruction and the critical role of fluorine,demonstrating the catalytic performance of metal fluorides from the perspectives of reconstruction mechanism and process analysis.Finally,we provide a summary and outlook for this field,aiming to offer guidance for future breakthroughs in the energy storage and conversion applications of metal fluorides.展开更多
Dissolved copper and iron ions are regarded as friendly and economic catalysts for peroxymonosulfate(PMS)activation,however,neither Cu(Ⅱ)nor Fe(Ⅲ)shows efficient catalytic performance because of the slow rates of Cu...Dissolved copper and iron ions are regarded as friendly and economic catalysts for peroxymonosulfate(PMS)activation,however,neither Cu(Ⅱ)nor Fe(Ⅲ)shows efficient catalytic performance because of the slow rates of Cu(Ⅱ)/Cu(Ⅰ)and Fe(Ⅲ)/Fe(Ⅱ)cycles.Innovatively,we observed a significant enhancement on the degradation of organic contaminants when Cu(Ⅱ)and Fe(Ⅲ)were coupled to activate PMS in borate(BA)buffer.The degradation efficiency of Rhodamine B(RhB,20μmol/L)reached up to 96.3%within 10 min,which was higher than the sum of individual Cu(Ⅱ)-and Fe(Ⅲ)-activated PMS process.Sulfate radical,hydroxyl radical and high-valent metal ions(i.e.,Cu(Ⅲ)and Fe(IV))were identified as the working reactive species for RhB removal in Cu(Ⅱ)/Fe(Ⅲ)/PMS/BA system,while the last played a predominated role.The presence of BA dramatically facilitated the reduction of Cu(Ⅱ)to Cu(Ⅰ)via chelating with Cu(Ⅱ)followed by Fe(Ⅲ)reduction by Cu(Ⅰ),resulting in enhanced PMS activation by Cu(Ⅰ)and Fe(Ⅱ)as well as accelerated generation of reactive species.Additionally,the strong buffering capacity of BA to stabilize the solution pH was satisfying for the pollutants degradation since a slightly alkaline environment favored the PMS activation by coupling Cu(Ⅱ)and Fe(Ⅲ).In a word,this work provides a brand-new insight into the outstanding PMS activation by homogeneous bimetals and an expanded application of iron-based advanced oxidation processes in alkaline conditions.展开更多
The Jiuyishan granitic complex,located in the Nanling Range,South China,is composed of five granitic plutons(Xuehuading,Jinjiling,Pangxiemu,Shaziling and Xishan).Zircon U-Pb dating of four plutons(Jinjiling,Pangxiemu,...The Jiuyishan granitic complex,located in the Nanling Range,South China,is composed of five granitic plutons(Xuehuading,Jinjiling,Pangxiemu,Shaziling and Xishan).Zircon U-Pb dating of four plutons(Jinjiling,Pangxiemu,Shaziling and Xishan)yielded similar ages of approximately 153 Ma,indicating indistinguishable ages within error.Three plutons except the Shaziling pluton,have consistentε_(Nd)(t)(-7.8 to-5.8)andε_(Hf)(t)(-9.1 to-2.2)values,which are similar to those of the lower crustal granulitic metasedimentary and meta-igneous rocks in South China.Compared to other three plutons,the Shaziling pluton has consistentε_(Nd)(t)(-7.4 to-6.8)andε_(Hf)(t)(-7.5 to-4.7)values and shows similar source,but the Shaziling mafic microgranular enclaves(MMEs)show variableε_(Hf)(t)(-14.2 to 4.8)values,indicating a remarkable mantle magma injection of the Shaziling pluton.Zircon Ce/Sm-Yb/Gd,whole-rock CaO-P_(2)O_(5)and CaO-TiO_(2)linear trends reveal that from the Xishan to the Shaziling and from the Jinjiling to the Pangxiemu granites,they experienced apatite and titanite fractionation,respectively.Zircon Th,U,Nb,Ta,Hf,Ti,Y,P and rare earth element(REE)contents and whole-rock Sr,Ba and Rb contents also show that the Shaziling,Xishan,Jinjiling and Pangxiemu granites followed a discontinuous evolutionary series,but the Pangxiemu granites exhibit highly evolved nature.Four main controlling factors of W-Sn and rare metal mineralization in granitic rocks were discussed,and we found that the mineralization in Jiuyishan granitic complex was mainly controlled by the fractionation degree and crystallization temperature,but were rarely affected by oxygen fugacity and mantle material input.The Pangxiemu granites show particularly higher Rb and Ta contents than the other three plutons,implying that the ore deposits developed in the Jiuyishan Complex were directly related to the most evolved Pangxiemu pluton,with the occurrence of Rb and Ta as the most likely rare metal mineralization in the Jiuyishan District.A crystal mush model is proposed to interpret the petrogenetic and mineralizing processes of the Jiuyishan granitic complex.展开更多
Thermally conductive papers with electrical insulation and mechanical robustness are essential for efficient thermal management in modern electronics.In this study,we introduced a metal ion-assisted interfacial crossl...Thermally conductive papers with electrical insulation and mechanical robustness are essential for efficient thermal management in modern electronics.In this study,we introduced a metal ion-assisted interfacial crosslinking strategy to strengthen sugarfunctionalized graphene fluoride(SGF)and cellulose nanofibers(CNF)by hydrogen bonding and metal ion crosslinking that leads to simultaneous enhancements in thermal conductivity and mechanical properties.The facile sugarassisted ball-milling exfoliation method was developed to achieve the exfoliation of graphite fluoride and hydroxyl group functionalization on the surface of graphene fluoride.Thanks to the good dispersibility of the SGF sheets in water,the flexible SGF/CNF composite papers with hydrogen bonding were prepared via vacuum-assisted filtration.We introduced hydrogen bonding and metal ion crosslinking into SGF/CNF papers to obtain densely packed composite papers.Ca^(2+)or Al^(3+)ion-crosslinked SGF/CNF papers exhibited superior thermal and mechanical properties owing to hydrogen bonding and metal ion crosslinking.SGF/CNF-Ca^(2+)and SGF/CNF-Al^(3+)papers at 50 wt%of SGF yield in-plane thermal conductivities of 72.93 and 75.02 W m^(-1) K^(-1),and tensile strengths of 121.5 and 135.7 MPa,respectively.A thermal percolation value was observed at 12.6 vol%of SGF filler content.In addition,the SGF/CNF papers exhibited electrical insulation properties.These remarkable characteristics of the metal ion-crosslinked SGF/CNF papers are attributed to the densely packed structures caused by the strong interfacial interactions from hydrogen bonding as well as metal ion-crosslinking that could promote phonon transport.High-performance metal ion-crosslinked SGF/CNF papers with these fascinating advantages offer great potential for the thermal management of flexible electronics.展开更多
This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides(M/SLDH)through spontaneous redox and sulfurization processes.The developed Ag/SLDH and Pt/SLDH catalysts with abun...This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides(M/SLDH)through spontaneous redox and sulfurization processes.The developed Ag/SLDH and Pt/SLDH catalysts with abundant heterogeneous interfaces and hierarchical nanostructures demonstrated outstanding oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)performance,achieving low overpotentials of 212 and 35 mV at 10 mA cm^(-2)in 1 M KOH,respectively.As both anode and cathode in water splitting,they required only 1.47 V to reach 10 mA cm^(-2)and exhibited high structural robustness,maintaining stability at 1000 mA cm^(-2)for 300 h.In-situ Raman analysis revealed that the synergistic effects of metal nanoparticles and S doping significantly promote the transformation into the S-Co1-xFexOOH layer,which serves as the active phase for water oxidation.Additionally,ultraviolet photoelectron spectroscopy(UPS)and density functional theory(DFT)analyses indicated that incorporating metal nanoparticles and S doping increase electron density near the Fermi level and reduce reaction energy barriers,thus enhancing intrinsic OER and HER activities.This study provides a scalable strategy for synthesizing high-performance electrocatalysts for water splitting,with promising potential for broader applications.展开更多
For the development of high-performance metallic glasses,enhancing their stability against viscous flow and crystallization is a primary objective.Vapor deposition or prolonged annealing is an effective method to impr...For the development of high-performance metallic glasses,enhancing their stability against viscous flow and crystallization is a primary objective.Vapor deposition or prolonged annealing is an effective method to improve glass stability,shown by increased glass transition temperature(Tg)and crystallization temperature(Tx).This contributes to the development of ultra-stable metallic glasses.Herein,we demonstrate that modulating the quenching temperature can also produce ultra-stable metallic glasses,as evidenced by an increase in Tx of 17-30 K in Cu-based metallic glasses.By modulating the quenching temperature,separated primary phases,secondary phases,and even nano-oxides can be obtained in the metallic glasses.Notably,metastable phases such as Cu-rich precipitates arising from secondary phase separation play a crucial role in enhancing glass stability.However,the enhancement of the stability of the glass has only a negligible effect on its mechanical properties.This study implies that different melt thermodynamic states generated by liquid-liquid separation and transition collectively determine the frozen-in glass structure.The results of this study will be helpful for the development of ultra-stable bulk glasses.展开更多
基金National Natural Science Foundation of China(U22A20191)。
文摘Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects.
基金supported by National Natural Science Foundation of China(52302034,52402060,52202201,52021006)Beijing National Laboratory for Molecular Sciences(BNLMS-CXTD202001)+1 种基金Shenzhen Science and Technology Innovation Commission(KQTD20221101115627004)China Postdoctoral Science Foundation(2024T170972)。
文摘Graphdiyne(GDY)is a two-dimensional carbon allotrope with exceptional physical and chemical properties that is gaining increasing attention.However,its efficient and scalable synthesis remains a significant challenge.We present a microwave-assisted approach for its continuous,large-scale production which enables synthesis at a rate of 0.6 g/h,with a yield of up to 90%.The synthesized GDY nanosheets have an average diameter of 246 nm and a thickness of 4 nm.We used GDY as a stable coating for potassium(K)metal anodes(K@GDY),taking advantage of its unique molecular structure to provide favorable paths for K-ion transport.This modification significantly inhibited dendrite formation and improved the cycling stability of K metal batteries.Full-cells with perylene-3,4,9,10-tetracarboxylic dianhydride(PTCDA)cathodes showed the clear superiority of the K@GDY anodes over bare K anodes in terms of performance,stability,and cycle life.The K@GDY maintained a stable voltage plateau and gave an excellent capacity retention after 600 cycles with nearly 100%Coulombic efficiency.This work not only provides a scalable and efficient way for GDY synthesis but also opens new possibilities for its use in energy storage and other advanced technologies.
文摘To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bispyridylanthrahydrazone(9,10‑PAH)were designed and synthesized.Utilizing 9‑PAH and 9,10‑PAH as promising anticancer ligands,their respective copper complexes,namely[Cu(L1)Cl_(2)]Cl(1)and{[Cu_(4)(μ_(2)‑Cl)_(3)Cl_(4)(9,10‑PAH)_(2)(DMSO)_(2)]Cl_(2)}_(n)(2),were subsequently synthesized,where the new ligand L1 is formed by coupling two 9‑PAH ligands in the coordination reaction.The chemical and crystal structures of 1 and 2 were elucidated by IR,MS,elemental analysis,and single‑crystal X‑ray diffraction.Complex 1 forms a mononuclear structure.L1 coordinates with Cu through its three N atoms,together with two Cl atoms,to form a five‑coordinated square pyramidal geometry.Complex 2 constitutes a polymeric structure,wherein each structural unit centrosymmetrically encompasses two five‑coordinated binuclear copper complexes(Cu1,Cu2)of 9,10‑PAH,with similar square pyramidal geometry.A chlorine atom(Cl_(2)),located at the symmetry center,bridges Cu1 and Cu1A to connect the two binuclear copper structures.Meanwhile,the two five‑coordinated Cu2 atoms symmetrically bridge the adjacent structural units via one coordinated Cl atom,respectively,thus forming a 1D chain‑like polymeric structure.In vitro anticancer activity assessments revealed that 1 and 2 showed significant cytotoxicity even higher than cisplatin.Specifically,the IC_(50)values of 2 against HeLa‑229 and SK‑OV‑3 cancer cell lines were determined to be(5.92±0.32)μmol·L^(-1)and(6.48±0.39)μmol·L^(-1),respectively.2 could also block the proliferation of HeLa‑229 cells in S phase and significantly induce cell apoptosis.In addition,fluorescence quenching competition experiments suggested that 2 might interact with DNA by an intercalative binding mode,offering insights into its underlying anticancer mechanism.CCDC:2388918,1;2388919,2.
基金supported by the National Natural Science Foundation of China(Nos.52100184,and U22A20617).
文摘Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remediation of heavy metals in agricultural soils are crucial.These two aspects support each other,forming a close and complete decisionmaking chain.Therefore,this review systematically summarizes the distribution characteristics of soil heavy metal pollution,the correlation between soil and crop heavy metal contents,the presence pattern and migration and transformation mode of heavy metals in the soil-crop system.The advantages and disadvantages of the risk evaluation tools and models of heavy metal pollution in farmland are further outlined,which provides important guidance for an in-depth understanding of the characteristics of heavymetal pollution in farmland soils and the assessment of the environmental risk.Soil remediation strategies involve multiple physical,chemical,biological and even combined technologies,and this paper compares the potential and effect of the above current remediation technologies in heavy metal polluted farmland soils.Finally,the main problems and possible research directions of future heavy metal risk assessment and remediation technologies in agricultural soils are prospected.This review provides new ideas for effective assessment and selection of remediation technologies based on the characterization of soil heavy metals.
文摘AgVO_(3)/ZIF-8 composites with enhanced photocatalytic effect were prepared by the combination of AgVO_(3)and ZIF-8.X-ray diffraction(XRD),scanning electron microscopy(SEM),high-power transmission electron microscopy(HRTEM),X-ray photoelectron spectroscopy(XPS),ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS),photoluminescence(PL)spectroscopy,electron spin resonance(ESR)spectroscopy,transient photocurrent and electrochemical impedance spectroscopy(EIS)were used to characterize binary composites.Tetracycline(TC)was used as a substrate to study the performance efficiency of the degradation of photocatalysts under light conditions,and the degradation effect of TC was also evaluated under different mass concentrations and ionic contents.In addition,we further investigated the photocatalytic mechanism of the binary composite material AgVO_(3)/ZIF-8 and identified the key active components responsible for the catalytic degradation of this new photocatalyst.The experimental results show that the degradation efficiency of 10%-AZ,prepared with a molar ratio of 10%AgVO_(3)and ZIF-8 to TC,was 75.0%.This indicates that the photocatalytic activity can be maintained even under a certain ionic content,making it a suitable photocatalyst for optimal use.In addition,the photocatalytic mechanism of binary composites was further studied by the active species trapping experiment.
文摘Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nanorods,which had many voids.The S-FeCoTA catalysts exhibited excellent electrochemical oxygen evolution reaction(OER)performance with a low overpotential of 273 mV at 10 mA·cm^(-2)and a small Tafel slope of 36 mV·dec^(-1)in 1 mol·L^(-1)KOH.The potential remained at 1.48 V(vs RHE)at 10 mA·cm^(-2)under continuous testing for 15 h,implying that S-FeCoTA had good stability.The Faraday efficiency of S-FeCoTA was 94%.The outstanding OER activity of S-FeCoTA is attributed to the synergistic effects among S,Fe,and Co,thus promoting electron transfer,reducing the reaction kinetic barrier,and enhancing the OER performance.
文摘(2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under solvothermal conditions,to react with transition metals achieving four novel metal-organic frameworks(MOFs):[Zn(IP)(L_(1))]_(n)(1),{[Cd(IP)(L_(1))]·H_(2)O}_(n)(2),{[Co(IP)(L_(1))]·H_(2)O}_(n)(3),and[Zn(IP)(L_(2))(H_(2)O)]_(n)(4).MOFs 1-4 have been characterized by single-crystal X-ray diffraction,powder X-ray diffraction,thermogravimetry,and elemental analysis.Single-crystal X-ray diffraction shows that MOF 1 crystallizes in the monoclinic crystal system with space group P2_(1)/n,and MOFs 2-4 belong to the triclinic system with the P1 space group.1-3 are 2D sheet structures,2 and 3 have similar structural characters,whereas 4 is a 1D chain structure.Furthermore,1-3 exhibited certain photocatalytic capability in the degradation of rhodamine B(Rh B)and pararosaniline hydrochloride(PH).4could be used as a heterogeneous catalyst for the Knoevenagel reaction starting with benzaldehyde derivative and malononitrile.4 could promote the reaction to achieve corresponding products in moderate yields within 3 h.Moreover,the catalyst exhibited recyclability for up to three cycles without significantly dropping its activity.A mechanism for MOF 4 catalyzed Knoevenagel condensation reaction of aromatic aldehyde and malononitrile has been initially proposed.CCDC:2356488,1;2356497,2;2356499,3;2356498,4.
基金financial support by the National Natural Science Foundation of China(No.52374293)Zhongyuan Science and Technology Innovation Leading Talent Project,China(No.224200510025)+1 种基金the Science and Technology Innovation Program of Hunan Province,China(No.2022RC1123)One of the authors,Hong-bo ZENG,gratefully acknowledges the support from the Natural Sciences and Engineering Research Council of Canada(NSERC)and the Canada Research Chairs Program.
文摘Lithium-ion batteries(LIBs)are the most popular energy storage devices due to their high energy density,high operating voltage,and long cycle life.However,green and effective recycling methods are needed because LIBs contain heavy metals such as Co,Ni,and Mn and organic compounds inside,which seriously threaten human health and the environment.In this work,we review the current status of spent LIB recycling,discuss the traditional pyrometallurgical and hydrometallurgical recovery processes,and summarize the existing short-process recovery technologies such as salt-assisted roasting,flotation processes,and direct recycling.Finally,we analyze the problems and potential research prospects of the current recycling process,and point out that the multidisciplinary integration of recycling will become the mainstream technology for the development of spent LIBs.
基金supported by the National Natural Science Foundation of China(No.52371240)the Natural Science Foundation of Jiangsu Province(No.BK20230556)+2 种基金China Postdoctoral Science Foundation(No.2022M722686)Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2023ZB701)The Big Data Computing Center of Southeast University.
文摘Metal-iodine batteries have attracted widespread attention due to their long cycle life,high energy density,remarkable charging capability and low self-discharge rate.Nevertheless,this development is hampered by the challenges of the iodine cathode and metal anode,including the hydrogen evolution reaction(HER),sluggish kinetics,shuttle effect of polyiodine ion at the cathode and dendrite formation,corrosion and passivation at the anode.This review summarizes recent developments in metaliodine batteries,including zinc-iodine batteries,lithiumiodine batteries,sodium-iodine batteries,etc.The challenges in the cathode,anode,electrolyte and separator of metal-iodine batteries are discussed,along with the corresponding design and synthesis strategies and specific methods to improve the electrochemical performance.Selecting appropriate cathode hosts,constructing surface protective layers,adding anode additives,making threedimensional anode designs and employing better electrolytes and functional separators to obstruct the production and shuttling of polyiodine ions are highlighted.Finally,future guidelines and directions for the development of metal-iodine batteries are proposed.
基金supported by the National Natural Science Foundation of China(Nos.52377026 and 52301192)the Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)+3 种基金the Postdoctoral Fellow-ship Program of CPSF under Grant Number(No.GZB20240327)the Shandong Postdoctoral Science Foundation(No.SDCX-ZG-202400275)the Qingdao Postdoctoral Application Research Project(No.QDBSH20240102023)the Qingchuang Talents Induction Program of Shandong Higher Education Institution(Research and Innovation Team of Structural-Functional Polymer Composites).
文摘Reasonable manipulation of component and microstructure is considered as a potential route to realize high-performance microwave absorber.In this paper,micro-sized hexapod-like CuS/Cu_(9)S_(5) composites were synthesized via a facile approach involving the solvothermal method and subsequent sulfuration treatment.The resultant CuS/Cu_(9)S_(5) exhibited superb microwave absorbing capacity with a minimum reflection loss(RLmin)of-59.38 dB at 2.7 mm.The maximum effective absorption bandwidth(EABmax)was 7.44 GHz(10.56-18 GHz)when the thickness was reduced to 2.3 mm.The outstanding microwave absorbing ability of CuS/Cu_(9)S_(5) composites is mainly related to its unique hexapod shape and the formation of heterogeneous interfaces.The unique hexapod shape significantly promotes the multi-reflection of the incident electromagnetic wave(EMW)increasing the attenuation path of EMWs in the material.Hetero-geneous interfaces between CuS/Cu_(9)S_(5) enable powerful interface polarization,contributing to the atten-uation of EMWs propagating in the medium.In addition,the EMW absorption performance of CuS/Cu_(9)S_(5) composites is also inseparable from the conduction loss.This study provides a strong reference for the research of EMW absorbent materials based on transition metal sulfides.
基金supported by the Fundamental Research Funds for the Central Universities(No.22120230104).
文摘High-entropy alloy(HEA)nanoparticles(NPs)have attracted great attention in electrocatalysis due to their tailorable complex compositions and unique properties.Herein,we introduce Fe,Co,Ni,Cr and Mn into the metal-polyphenol coordination system to prepare HEA NPs enclosed in N-doped carbon(FeCoNiCrMn)with great potential for catalyzing oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).The unique high-entropy structural characteristics in FeCoNiCrMn facilitate effective interplay between metal species,leading to improved ORR(E_(1/2)=0.89 V)and OER(η=330 mV,j=10 mA·cm^(−2))activity.Additionally,FeCoNiCrMn exhibits excellent open-circuit voltage(1.523 V),power density(110 mW·cm^(−2))and long-term durability,outperforming Pt/C+IrO_(2) electrodes as a cathode catalyst in Zn-air batteries(ZABs).Such polyphenol-assisted alloying method broadens and simplifies the development of HEA electrocatalysts for high-performance ZABs.
基金supported by the GRDC(Global Research Development Center)Cooperative Hub Program through the National Research Foundation of Korea(NRF),funded by the Ministry of Science and ICT(MSIT)(No.RS-2023-00257595).
文摘Liquid metals(LMs),because of their ability to remain in a liquid state at room temperature,render them highly versatile for applications in electronics,energy storage,medicine,and robotics.Among various LMs,Ga-based LMs exhibit minimal cytotoxicity,low viscosity,high thermal and electrical conductivities,and excellent wettability.Therefore,Ga-based LM composites(LMCs)have emerged as a recent research focus.Recent advancements have focused on novel fabrication techniques and applications spanning energy storage,flexible electronics,and biomedical devices.Particularly noteworthy are the developments in wearable sensors and electronic skins,which hold promise for healthcare monitoring and human-machine interfaces.Despite their potential,challenges,such as oxidative susceptibil-ity and biocompatibility,remain.Creating bio-based LMC materials is a promising approach to address these issues while exploring new avenues to optimize LMC performance and broaden its application domains.This review provides a concise overview of the recent trends in LMC research,highlights their transformative impacts,and outlines key directions for future investigation and development.
基金National Natural Science Foundation of China,Grant/Award Number:51073067Scientific and Technological Development Program of Jilin Province,Grant/Award Number:20220201138GX.
文摘In recent years,renewable energy sources,which aim to replace rapidly depleting fossil fuels,face challenges due to limited energy storage and conversion technologies.To enhance energy storage and conversion efficiency,extensive research has been conducted in the academic community on numerous potential materials.Among these materials,metal fluorides have attracted significant attention due to their ionic metal-fluorine bonds and tunable electronic structures,attributed to the highest electronegativity of fluorine in their chemical composition.This makes them promising candidates for future electrochemical applications in various fields.However,metal fluorides encounter various challenges in different application directions.Therefore,we comprehensively review the applications of metal fluorides in the field of energy storage and conversion,aiming to deepen our understanding of their exhibited characteristics in different electrochemical processes.In this paper,we summarize the difficulties and improvement methods encountered in different types of battery applications and several typical electrode optimization strategies in the field of supercapacitors.In the field of water electrolysis,we focus on surface reconstruction and the critical role of fluorine,demonstrating the catalytic performance of metal fluorides from the perspectives of reconstruction mechanism and process analysis.Finally,we provide a summary and outlook for this field,aiming to offer guidance for future breakthroughs in the energy storage and conversion applications of metal fluorides.
基金supported by the Sichuan Science and Technology Program(No.2021YJ0385)the Project in Yangtze River Ecological Environment Protection and Restoration(No.2022-LHYJ-02-0509-08).
文摘Dissolved copper and iron ions are regarded as friendly and economic catalysts for peroxymonosulfate(PMS)activation,however,neither Cu(Ⅱ)nor Fe(Ⅲ)shows efficient catalytic performance because of the slow rates of Cu(Ⅱ)/Cu(Ⅰ)and Fe(Ⅲ)/Fe(Ⅱ)cycles.Innovatively,we observed a significant enhancement on the degradation of organic contaminants when Cu(Ⅱ)and Fe(Ⅲ)were coupled to activate PMS in borate(BA)buffer.The degradation efficiency of Rhodamine B(RhB,20μmol/L)reached up to 96.3%within 10 min,which was higher than the sum of individual Cu(Ⅱ)-and Fe(Ⅲ)-activated PMS process.Sulfate radical,hydroxyl radical and high-valent metal ions(i.e.,Cu(Ⅲ)and Fe(IV))were identified as the working reactive species for RhB removal in Cu(Ⅱ)/Fe(Ⅲ)/PMS/BA system,while the last played a predominated role.The presence of BA dramatically facilitated the reduction of Cu(Ⅱ)to Cu(Ⅰ)via chelating with Cu(Ⅱ)followed by Fe(Ⅲ)reduction by Cu(Ⅰ),resulting in enhanced PMS activation by Cu(Ⅰ)and Fe(Ⅱ)as well as accelerated generation of reactive species.Additionally,the strong buffering capacity of BA to stabilize the solution pH was satisfying for the pollutants degradation since a slightly alkaline environment favored the PMS activation by coupling Cu(Ⅱ)and Fe(Ⅲ).In a word,this work provides a brand-new insight into the outstanding PMS activation by homogeneous bimetals and an expanded application of iron-based advanced oxidation processes in alkaline conditions.
基金financially supported by the Provincial Natural Science Foundation of Hunan(Nos.2019JJ50831,2023JJ30505 and 2023JJ40541)the China Postdoctoral Science Foundation(Nos.2017M622597 and 2021M690591)+2 种基金the Open Research Fund Program of Fundamental Science on Radioactive Geology and Exploration Technology Laboratory(East China University of Technology)(No.2022RGET04)the National Foreign Expert Project(No.G2022029012L)the National Nature Science Foundation of China(No.41002022)。
文摘The Jiuyishan granitic complex,located in the Nanling Range,South China,is composed of five granitic plutons(Xuehuading,Jinjiling,Pangxiemu,Shaziling and Xishan).Zircon U-Pb dating of four plutons(Jinjiling,Pangxiemu,Shaziling and Xishan)yielded similar ages of approximately 153 Ma,indicating indistinguishable ages within error.Three plutons except the Shaziling pluton,have consistentε_(Nd)(t)(-7.8 to-5.8)andε_(Hf)(t)(-9.1 to-2.2)values,which are similar to those of the lower crustal granulitic metasedimentary and meta-igneous rocks in South China.Compared to other three plutons,the Shaziling pluton has consistentε_(Nd)(t)(-7.4 to-6.8)andε_(Hf)(t)(-7.5 to-4.7)values and shows similar source,but the Shaziling mafic microgranular enclaves(MMEs)show variableε_(Hf)(t)(-14.2 to 4.8)values,indicating a remarkable mantle magma injection of the Shaziling pluton.Zircon Ce/Sm-Yb/Gd,whole-rock CaO-P_(2)O_(5)and CaO-TiO_(2)linear trends reveal that from the Xishan to the Shaziling and from the Jinjiling to the Pangxiemu granites,they experienced apatite and titanite fractionation,respectively.Zircon Th,U,Nb,Ta,Hf,Ti,Y,P and rare earth element(REE)contents and whole-rock Sr,Ba and Rb contents also show that the Shaziling,Xishan,Jinjiling and Pangxiemu granites followed a discontinuous evolutionary series,but the Pangxiemu granites exhibit highly evolved nature.Four main controlling factors of W-Sn and rare metal mineralization in granitic rocks were discussed,and we found that the mineralization in Jiuyishan granitic complex was mainly controlled by the fractionation degree and crystallization temperature,but were rarely affected by oxygen fugacity and mantle material input.The Pangxiemu granites show particularly higher Rb and Ta contents than the other three plutons,implying that the ore deposits developed in the Jiuyishan Complex were directly related to the most evolved Pangxiemu pluton,with the occurrence of Rb and Ta as the most likely rare metal mineralization in the Jiuyishan District.A crystal mush model is proposed to interpret the petrogenetic and mineralizing processes of the Jiuyishan granitic complex.
基金supported by the Basic Science Program(No.2022R1A2C2009700)through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICTthe Basic Science Research Capacity Enhancement Project(National Research Facilities and Equipment Center)through the Korea Ba-sic Science Institute funded by the Ministry of Education(No.2019R1A6C1010047)the Industrial Strategic Technology Development Program(No.20013248)through Korea Evaluation In-stitute of Industrial Technology funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea).
文摘Thermally conductive papers with electrical insulation and mechanical robustness are essential for efficient thermal management in modern electronics.In this study,we introduced a metal ion-assisted interfacial crosslinking strategy to strengthen sugarfunctionalized graphene fluoride(SGF)and cellulose nanofibers(CNF)by hydrogen bonding and metal ion crosslinking that leads to simultaneous enhancements in thermal conductivity and mechanical properties.The facile sugarassisted ball-milling exfoliation method was developed to achieve the exfoliation of graphite fluoride and hydroxyl group functionalization on the surface of graphene fluoride.Thanks to the good dispersibility of the SGF sheets in water,the flexible SGF/CNF composite papers with hydrogen bonding were prepared via vacuum-assisted filtration.We introduced hydrogen bonding and metal ion crosslinking into SGF/CNF papers to obtain densely packed composite papers.Ca^(2+)or Al^(3+)ion-crosslinked SGF/CNF papers exhibited superior thermal and mechanical properties owing to hydrogen bonding and metal ion crosslinking.SGF/CNF-Ca^(2+)and SGF/CNF-Al^(3+)papers at 50 wt%of SGF yield in-plane thermal conductivities of 72.93 and 75.02 W m^(-1) K^(-1),and tensile strengths of 121.5 and 135.7 MPa,respectively.A thermal percolation value was observed at 12.6 vol%of SGF filler content.In addition,the SGF/CNF papers exhibited electrical insulation properties.These remarkable characteristics of the metal ion-crosslinked SGF/CNF papers are attributed to the densely packed structures caused by the strong interfacial interactions from hydrogen bonding as well as metal ion-crosslinking that could promote phonon transport.High-performance metal ion-crosslinked SGF/CNF papers with these fascinating advantages offer great potential for the thermal management of flexible electronics.
基金National Programs for NanoKey Project(2022YFA1504002)National Natural Science Foundation of China(22078233)。
文摘This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides(M/SLDH)through spontaneous redox and sulfurization processes.The developed Ag/SLDH and Pt/SLDH catalysts with abundant heterogeneous interfaces and hierarchical nanostructures demonstrated outstanding oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)performance,achieving low overpotentials of 212 and 35 mV at 10 mA cm^(-2)in 1 M KOH,respectively.As both anode and cathode in water splitting,they required only 1.47 V to reach 10 mA cm^(-2)and exhibited high structural robustness,maintaining stability at 1000 mA cm^(-2)for 300 h.In-situ Raman analysis revealed that the synergistic effects of metal nanoparticles and S doping significantly promote the transformation into the S-Co1-xFexOOH layer,which serves as the active phase for water oxidation.Additionally,ultraviolet photoelectron spectroscopy(UPS)and density functional theory(DFT)analyses indicated that incorporating metal nanoparticles and S doping increase electron density near the Fermi level and reduce reaction energy barriers,thus enhancing intrinsic OER and HER activities.This study provides a scalable strategy for synthesizing high-performance electrocatalysts for water splitting,with promising potential for broader applications.
基金supported by the National Natural Science Foundation of China(Nos.51827801,52371152,and 51971120).
文摘For the development of high-performance metallic glasses,enhancing their stability against viscous flow and crystallization is a primary objective.Vapor deposition or prolonged annealing is an effective method to improve glass stability,shown by increased glass transition temperature(Tg)and crystallization temperature(Tx).This contributes to the development of ultra-stable metallic glasses.Herein,we demonstrate that modulating the quenching temperature can also produce ultra-stable metallic glasses,as evidenced by an increase in Tx of 17-30 K in Cu-based metallic glasses.By modulating the quenching temperature,separated primary phases,secondary phases,and even nano-oxides can be obtained in the metallic glasses.Notably,metastable phases such as Cu-rich precipitates arising from secondary phase separation play a crucial role in enhancing glass stability.However,the enhancement of the stability of the glass has only a negligible effect on its mechanical properties.This study implies that different melt thermodynamic states generated by liquid-liquid separation and transition collectively determine the frozen-in glass structure.The results of this study will be helpful for the development of ultra-stable bulk glasses.
