A tin film of 320 nm in thickness on Cu foil and its composite film with graphite of-50 nm in thickness on it were fabricated by magnetron sputtering. The surface morphology, composition, surface distributions of allo...A tin film of 320 nm in thickness on Cu foil and its composite film with graphite of-50 nm in thickness on it were fabricated by magnetron sputtering. The surface morphology, composition, surface distributions of alloy elements, and lithium intercalation/de-intercalation behaviors of the fabricated films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), electron probe microanalyzer (EPMA), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma atomic emission spectrometry (ICP), cyclic voltammetry (CV), and galvanostatic charge/discharge (GC) measurements. It is found that the lithium intercalation/de-intercalation behavior of the Sn film can be significantly improved by its composite with graphite. With cycling, the discharge capacity of the Sn film without composite changes from 570 mAh/g of the 2nd cycle to 270 mAh/g of the 20th cycle, and its efficiency for the discharge and charge is between 90% and 95%. Nevertheless, the discharge capacity of the composite Sn/C film changes from 575 mAh/g of the 2nd cycle to 515 mAh/g of the 20th cycle, and its efficiency for the discharge and charge is between 95% and 100%. The performance improvement of tin by its composite with graphite is ascribed to the retardation of the bulk tin cracking from volume change during lithium intercalation and de-intercalation, which leads to the pulverization of tin.展开更多
V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve th...V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve the stability,organic small molecule choline chloride intercalation is used to expand the spacing of the vanadium pentoxide layers and increase the cycling stability.Therefore,we consider the introduction of Sr^(2+)to cointercalate with choline chloride.Here,we synthes-ized vanadium pentoxide cointercalated with Sr^(2+)and choline ions(Ch^(+))via a simple hydrothermal method.The electro-chemical performance shows an enhanced cathode capacitance contribution of Sr&Ch-V_(2)O_(5),with a discharge capacity of 526 mAh·g^(-1)at 0.1 A·g^(-1)and a retention rate of 78.9%after 2000 cycles at 5 A·g^(-1).This work offers a novel strategy for the design of organic‒inorganic hybrid materials for use as cathodes in aqueous zinc-ion batteries.展开更多
Intercalation catalysis research involves inserting metal ions,molecules,or ionic liquids into the layered structure of catalysts to adjust their electronic structure and surface properties,thereby optimizing catalyti...Intercalation catalysis research involves inserting metal ions,molecules,or ionic liquids into the layered structure of catalysts to adjust their electronic structure and surface properties,thereby optimizing catalytic reaction efficiency and selectivity[1–3].This technique has achieved significant progress in areas such as electrocatalysis,catalytic cracking,and energy conversion,especially in reactions like hydrogen generation,oxygen reduction,nitrogen reduction,and carbon dioxide reduction[4–6].Intercalation catalysis can enhance catalyst activity and selectivity,but challenges remain regarding stability,reusability,and industrial application.Future research will focus on developing new intercalation materials,optimizing catalyst design,and exploring their potential applications in complex environments[7].展开更多
Direct electrolysis of seawater offers a transformative technology for sustainable hydrogen production,circumventing the constraint of freshwater scarcity.However,the serious electrode corrosion and competitive chlori...Direct electrolysis of seawater offers a transformative technology for sustainable hydrogen production,circumventing the constraint of freshwater scarcity.However,the serious electrode corrosion and competitive chloride oxidation reactions make oxygen evolution reaction(OER)in seawater extremely challenging.Herein,the low-cost and scalable CoFe layered double hydroxides with Cl^(-)intercalation and decorated with Ce(OH)_(3)(named as CoFe-Cl^(-)/Ce(OH)_(3))catalyst is synthesized via rapid electrodeposition under ambient conditions,which is quickly reconstructed into a CeO_(2)decorated and Cl^(-)intercalated CoFeOOH(CoFeOOH-Cl^(-)/CeO_(2))during OER.Theoretical investigation reveals that Cl^(-)intercalation weakens the adsorption ability of Cl^(-)on Co/Fe atoms and hinders unfavorable coupling with chloride,thereby preventing the chlorine corrosion process and enhancing catalytic stability and activity.The CeO_(2)with hard Lewis acidity preferentially binds to OH-with harder Lewis base to ensure the OH-rich microenvironment around catalyst even under high current operating conditions,thus further enhancing stability and improving OER activity.The functionalized CoFe-Cl^(-)/Ce(OH)_(3)delivers 1000 mA cm^(-2)current density at only 329 mV overpotential with excellent stability for 1000 h under alkaline seawater.Electrochemical experiments elucidate the OER catalytic mechanism in which CeO_(2)serves as a co-catalyst for enriching OH-and CoFeOOH-Cl^(-)is the active species.Our work is a substantial step towards achieving massive and sustainable production of hydrogen fuel from immense seawater.展开更多
Two-dimensional(2D)organic-inorganic hybrid perovskites(OIHPs)have been developed as promising candidates for photodetection,owing to their excellent semiconducting features and structural tunability.However,as an imp...Two-dimensional(2D)organic-inorganic hybrid perovskites(OIHPs)have been developed as promising candidates for photodetection,owing to their excellent semiconducting features and structural tunability.However,as an important parameter for photodetection,the photoresponsive range of 2D OIHPs is usually modulated by finite metal-halide combinations,constraining their further development.The emerging aromatic amine-based alternating-cations-interlayered(A-ACI)hybrid perovskites that exhibit excellent charge transport and additional interlayered structural designability,provide an extra solution for achieving ideal photoresponsive range.Herein,for the first time,the photoresponsive range is successfully broadened in A-ACI hybrid perovskites(NMA)_(4)(FA)_(2)Pb_(3)Br_(12)(2)remolding from(NMA)_(4)(MA)_(2)Pb_(3)Br_(12)(1)(NMA=N-methylbenzylaminium,FA=formamidinium and MA=methylammonium).Particularly,1 and 2adopt an unprecedented configuration that NMA and MA/FA are alternately arranged in the interlayer in a 4:2 manner.Importantly,2 exhibits a narrower bandgap than 1,which can be ascribed to the lowlying conduct band composed of intercalation FAπ*orbitals.Meanwhile,2 possesses a shorter interlayer distance and flatter inorganic skeleton,synergistically facilitating the wider photo-absorption range and further endowing a broadening photoresponsive range(70 nm).This research not only enriches the perovskite family but also provides insights into structure-property relationships.展开更多
Magnesium-ion batteries hold promise as future energy storage solutions,yet current Mg cathodes are challenged by low voltage and specific capacity.Herein,we present an AI-driven workflow for discovering high-performa...Magnesium-ion batteries hold promise as future energy storage solutions,yet current Mg cathodes are challenged by low voltage and specific capacity.Herein,we present an AI-driven workflow for discovering high-performance Mg cathode materials.Utilizing the common characteristics of various ionic intercalation-type electrodes,we design and train a Crystal Graph Convolutional Neural Network model that can accurately predict electrode voltages for various ions with mean absolute errors(MAE)between0.25 and 0.33 V.By deploying the trained model to stable Mg compounds from Materials Project and GNoME AI dataset,we identify 160 high voltage structures out of 15,308 candidates with voltages above3.0 V and volumetric capacity over 800 mA h/cm^(3).We further train a precise NequIP model to facilitate accurate and rapid simulations of Mg ionic conductivity.From the 160 high voltage structures,the machine learning molecular dynamics simulations have selected 23 cathode materials with both high energy density and high ionic conductivity.This Al-driven workflow dramatically boosts the efficiency and precision of material discovery for multivalent ion batteries,paving the way for advanced Mg battery development.展开更多
MnBi_(2)Te_(4),which is emerging as an intrinsic antiferromagnetic(AFM)topological insulator,provides a unique platform to investigate the interplay between magnetism and topology.Modulating its magnetic properties en...MnBi_(2)Te_(4),which is emerging as an intrinsic antiferromagnetic(AFM)topological insulator,provides a unique platform to investigate the interplay between magnetism and topology.Modulating its magnetic properties enables the observation of exotic quantum phenomena such as the quantum anomalous Hall effect,axion insulator states,and Majorana fermions.While the intercalation of Bi_(2)Te_(3)can tune its magnetism,synthesizing pure-phase MnBi_(2)Te_(4)with uniform Bi_(2)Te_(3)intercalation remains challenging,and the fixed interlayer spacing of Bi_(2)Te_(3)limits magnetic coupling tunability.Here,we utilize electrochemical organic molecule intercalation to expand the van der Waals gap of MnBi_(2)Te_(4)and modulate its magnetic properties.Through x-ray diffraction(XRD)characterizations,we confirm that the interlayer spacing of MnBi_(2)Te_(4)is expanded from 13.6°A to 30.5°A and 61.0°A by intercalating quaternary ammonium cations(THA^(+)and CTA^(+)),respectively.The THA-MnBi_(2)Te_(4)exhibits dual complex magnetic behavior,combining AFM ordering with a Neel temperature(T_(N))of 12 K and a small ferromagnetic hysteresis loop at 2 K.The CTA-MnBi_(2)Te_(4)shows robust ferromagnetism,with a Curie point(T_(C))of 15 K,similar to that of the MnBi_(2)Te_(4)monolayer.These results demonstrate that remarkable changes in the magnetic properties of MnBi_(2)Te_(4)can be achieved via electrochemical intercalation,providing new insights into manipulating magnetism in layered magnetic materials.展开更多
Developing anode materials with high specific/volumetric capacities,high-rate capability,long-term cycles and low cost is significant for advanced sodium-ion storage.Herein,we report the hybrid TiO_(2)/graphite(TiO_(2...Developing anode materials with high specific/volumetric capacities,high-rate capability,long-term cycles and low cost is significant for advanced sodium-ion storage.Herein,we report the hybrid TiO_(2)/graphite(TiO_(2)/G)anodes for fast(dis)charging sodium-ion storage.Taking advantage of the rapid pseudocapacitive surface-redox on anatase TiO_(2)nanoparticles(NPs)and fast[Na(diglyme)_(x)]^(+)co-intercalation into graphite,the hybrid anodes display excellent rate capabilities.Additionally,the TiO_(2)NPs are able to fill into the interspaces among graphite flakes and the graphite provides continuous electron pathways,which largely boosts the volumetric capacities and rate performance.展开更多
Orthorhombic Nb_(2)O_(5)(T-Nb_(2)O_(5))is attractive for fast-charging Li-ion batteries,but it is still hard to realize rapid charge transfer kinetics for Li-ion storage.Herein,F-doped T-Nb_(2)O_(5) microflowers(F-Nb_(...Orthorhombic Nb_(2)O_(5)(T-Nb_(2)O_(5))is attractive for fast-charging Li-ion batteries,but it is still hard to realize rapid charge transfer kinetics for Li-ion storage.Herein,F-doped T-Nb_(2)O_(5) microflowers(F-Nb_(2)O_(5))are rationally synthesized through topotactic conversion.Specifically,F-Nb_(2)O_(5) are assembled by single-crystal nanoflakes with nearly 97%exposed(100)facet,which maximizes the exposure of the feasible Li^(+)transport pathways along loosely packed 4g atomic layers to the electrolytes,thus effectively enhancing the Li^(+)-intercalation performance.Besides,the band gap of F-Nb_(2)O_(5) is reduced to 2.87 eV due to the doping of F atoms,leading to enhanced electrical conductivity.The synergetic effects between tailored exposed crystal facets,F-doping,and ultrathin building blocks,speed up the Li^(+)/electron transfer kinetics and improve the pseudocapacitive properties of F-Nb_(2)O_(5).Therefore,F-Nb_(2)O_(5) exhibit superior rate capability(210.8 and 164.9 mAh g^(-1) at 1 and 10 C,respectively)and good long-term 10 C cycling performance(132.7 mAh g^(-1) after 1500 cycles).展开更多
Metallic zinc is an ideal anode material owing to its high theoretical capacity(819 mAh·g^(-1)),ecofriendliness,low cost and high safety,which have driven fast development of Zn-ion batteries(ZIBs).However,the pr...Metallic zinc is an ideal anode material owing to its high theoretical capacity(819 mAh·g^(-1)),ecofriendliness,low cost and high safety,which have driven fast development of Zn-ion batteries(ZIBs).However,the practical application of current ZIBs is significantly restricted by irregular dendrite growth of zinc anode and the low working voltage(usually<2 V)of cathode materials.Herein,we report a high-voltage Zn-based dualion battery(DIB),which is constructed by a graphite cathode,a Zn anode,and 3 M LiPF_(6)in the ethyl methyl carbonate(EMC)electrolyte.Under the corrosion interaction of Li^(+)ions,Zn^(2+)can be easily dissolved from Zn anode into the electrolyte to enable dendrite-free Zn^(2+)plating/stripping at the anode.Moreover,an aqueous carboxymethyl cellulose(CMC)binder is employed to generate a robust cathode electrolyte interface(CEI)layer on the graphite cathode,which renders ultrafast PF_(6)^(-)-de-/intercalation into graphite.The resultant Zn-graphite DIB operates stably at a high cut off voltage of 3.2 V,corresponding to an average output voltage of 2.2 V.After 9000cycles at 5C,the high capacity retention of 95.9% can be achieved with~100% Coulomb efficiency.Based on the mass of cathode material,our Zn-graphite battery exhibits ultrafast rate capability(60 C,a discharge time of 44 s)and high energy/power densities(208 Wh·kg^(-1)at 214 W·kg^(-1);142 Wh·kg^(-1)at 8692 W·kg^(-1)),which holds great promise for large-scale energy storage.展开更多
The typical metal chloride-graphite intercalation compounds(MC-GICs)inherit intercalation capacity,high charge conductivity,and high tap density from graphite,and these are considered as one of the promising alternati...The typical metal chloride-graphite intercalation compounds(MC-GICs)inherit intercalation capacity,high charge conductivity,and high tap density from graphite,and these are considered as one of the promising alternatives of graphite anode in rechargeable metal-ion batteries(MIBs).Notably,the special interlayer decoupling effects and the introduction of extra conversion capacity by metal chloride could greatly break the capacity limitation of graphite anodes and achieve higher energy density in MIBs.The optimization of both graphite host and metal chloride species with specific structures endows MC-GICs with design feasibility for different application requirements of different MIBs,such as several times the actual capacity compared to graphite anodes,rapid migration of large carriers,and other properties.Herein,a brief review has been provided with the latest understanding of conductivity characteristics and energy storage mechanisms of MC-GICs and their interesting performance features of full potential application in rechargeable MIBs.Based on the existing research of MC-GICs,necessary improvements and prospects in the near future have been put forward.展开更多
The poor electronic conductivity of metal-organic framework(MOF)materials hinders their direct application in the field of electrocatalysis in fuel cells.Herein,we proposed a strategy of embedding carbon nanotubes(CNT...The poor electronic conductivity of metal-organic framework(MOF)materials hinders their direct application in the field of electrocatalysis in fuel cells.Herein,we proposed a strategy of embedding carbon nanotubes(CNTs)during the growth process of MOF crystals,synthesizing a metalloporphyrin-based MOF catalyst TCPPCo-MOF-CNT with a unique CNT-intercalated MOF structure.Physical characterization revealed that the CNTs enhance the overall conductivity while retaining the original characteristics of the MOF and metalloporphyrin.Simultaneously,the insertion of CNTs generated adequate mesopores and created a hierarchical porous structure that enhances mass transfer efficiency.X-ray photoelectron spectroscopic analysis confirmed that the C atom in CNT changed the electron cloud density on the catalytic active center Co,optimizing the electronic structure.Consequently,the E_(1/2) of the TCPPCo-MOF-CNT catalyst under neutral conditions reached 0.77 V(vs.RHE),outperforming the catalyst without CNTs.When the TCPPCo-MOF-CNT was employed as the cathode catalyst in assembling microbial fuel cells(MFCs)with Nafion-117 as the proton exchange membrane,the maxi-mum power density of MFCs reached approximately 500 mW·m^(-2).展开更多
Two-dimensional MXenes are renowned for their remarkable electrical conductivity and electrochemical activity making them highly promising for electrode applications.However,the restacking of MXene nanosheets impairs ...Two-dimensional MXenes are renowned for their remarkable electrical conductivity and electrochemical activity making them highly promising for electrode applications.However,the restacking of MXene nanosheets impairs their functionality by reducing active sites and obstructing ionic transport.This study presents a facile synthesis approach for nickel-intercalated MXene,designed to enhance surface reactivity,avoid restacking,and achieve improved electrochemical performance.Electrochemical studies revealed that the nickel-MXene hybrid showed better cycling stability,retaining 83.7%of its capacity after 10000 cycles and attaining an energy density of 26 Wh kg^(-1) at a power density of 1872Wkg^(-1).It also exhibited overpotentials of 109 and 482 mV at 10 and 100 mA cm^(-2),respectively,in the hydrogen evolution reaction.To predict the structural and electrical alterations caused by nickel inclusion,as well as to understand the intercalation mechanism,spin-polarized density functional theory calculations were carried out.The theoretical results showed an improved carrier concentration for nickel-MXene.Nickel-MXene possessed superior electronic characteristics and surplus active sites with hexagonal closed-packed(hcp)edge sites,which enhanced electrochemical properties.Our results demonstrate that nickel intercalation prevents the restacking of MXene but also significantly improves their electrochemical characteristics,making them ideal for energy storage and catalytic applications.展开更多
The interaction between charge and spin degrees of freedom has always been the central issue of condensed matter physics,and transition metal dichalcogenides(TMDs)provide an ideal platform to study it benefiting from ...The interaction between charge and spin degrees of freedom has always been the central issue of condensed matter physics,and transition metal dichalcogenides(TMDs)provide an ideal platform to study it benefiting from their highly tunable properties.In this article,the influence of Fe intercalation in NbSe_(2)was elaborately investigated using a combination of techniques.Magnetic studies have shown that the insertion of Fe atoms induces an antiferromagnetic state in which the easy axis aligns out of the plane.The sign reversal of the magnetoresistance across the Neel temperature can be satisfactorily explained by the moderate interaction between electrons and local spins.The Hall and Seebeck measurements reveal a multi-band nature,and the contribution of various phonon scattering processes is discussed based on the thermal conductivity and specific heat data.展开更多
Transition metal-based compounds can serve as pre-catalysts to obtain genuine oxygen evolution reaction(OER)electrocatalysts in the form of oxyhydroxides through electrochemical activation.However,the role and existen...Transition metal-based compounds can serve as pre-catalysts to obtain genuine oxygen evolution reaction(OER)electrocatalysts in the form of oxyhydroxides through electrochemical activation.However,the role and existence form of leached oxygen anions are still controversial.Herein,we selected iron selenite-wrapped hydrated nickel molybdate(denoted as NiMoO/FeSeO)as a pre-catalyst to study the oxyanion effect.It is surprising to find that SeO_(2)-exists in the catalyst in the form of intercalation,which is different from previous studies that suggest that anions are doped with residual elements after electrochemical activation,or adsorbed on the catalyst surface.The experiment and theoretical calculations show that the existence of SeO_(4)^(2-)intercalation effectively adjusts the electronic structure of NiFeOOH,promotes intramolecular electron transfer and O-O release,and thus lowers the reaction energy barrier.As expected,the synthesized NiFeOOH-SeO only needs 202 and 285 mV to attain 100 and 1000 mA cm^(-2)in 1 M KOH.Further,the anion exchange membrane water electrolyzer(AEMWE)consisting of NiFeOOHSeO anode and Pt/C cathode can reach 1 A cm^(-2)at 1.70 V and no significant attenuation within 300 h.Our findings provide insights into the mechanism,by which the intercalated oxyanions enhance the OER performance of NiFeOOH,thereby facilitating large-scale hydrogen production through AEMWE.展开更多
Highly dispersed tungsten carbide(WC) nanoparticles(NPs) sandwiched between few-layer reduced graphene oxide(RGO) have been successfully synthesized by using thiourea as an anchoring and inducing reagent.The met...Highly dispersed tungsten carbide(WC) nanoparticles(NPs) sandwiched between few-layer reduced graphene oxide(RGO) have been successfully synthesized by using thiourea as an anchoring and inducing reagent.The metatungstate ion,[H2W(12)O(40)]^6-,is assembled on thiourea-modified graphene oxide(GO) by an impregnation method.The WC NPs,with a mean diameter of 1.5 nm,are obtained through a process whereby ammonium metatungstate first turns to WS2,which then forms an intercalation compound with RGO before growing,in situ,to WC NPs.The Pt/WC-RGO electrocatalysts are fabricated by a microwave-assisted method.The intimate contacts between Pt,WC,and RGO are confirmed by X-ray diffraction,scanning electron microscope,transmission electron microscope,and Raman spectroscopy.For methanol oxidation,the Pt/WC-RGO electrocatalyst exhibited an electrochemical surface area value of 246.1 m^2/g Pt and a peak current density of1364.7 mA/mg Pt,which are,respectively,3.66 and 4.77 times greater than those of commercial Pt/C electrocatalyst(67.2 m^2/g Pt,286.0 mA/mg Pt).The excellent CO-poisoning resistance and long-term stability of the electrocatalyst are also evidenced by CO stripping,chronoamperometry,and accelerated durability testing.Because Pt/WC-RGO has higher catalytic activity compared with that of commercial Pt/C,as a result of its intercalated structure and synergistic effect,less Pt will be required for the same performance,which in turn will reduce the cost of the fuel cell.The present method is facile,efficient,and scalable for mass production of the nanomaterials.展开更多
With the development of stable alkali metal anodes,V_(2)O_(5) is gaining traction as a cathode material due to its high theoretical capacity and the ability to intercalate Li,Na and K ions.Herein,we report a method fo...With the development of stable alkali metal anodes,V_(2)O_(5) is gaining traction as a cathode material due to its high theoretical capacity and the ability to intercalate Li,Na and K ions.Herein,we report a method for synthesizing structured orthorhombic V_(2)O_(5) microspheres and investigate Li intercalation/deintercalation into this material.For industry adoption,the electrochemical behavior of V_(2)O_(5) as well as structural and phase transformation attributing to Li intercalation reaction must be further investigated.Our synthesized V_(2)O_(5) microspheres consisted of small primary particles that were strongly joined together and exhibited good cycle stability and rate capability,triggered by reversible volume change and rapid Li ion diffusion.In addition,the reversibility of phase transformation(a,e,d,c and xLixV_(2)O_(5))and valence state evolution(5+,4+,and 3.5+)during intercalation/de-intercalation were studied via in-situ X-ray powder diffraction and X-ray absorption near edge structure analyses.展开更多
Phenolic resin/montmorillonite intercalation composites were prepared by using the methods of pressing intercalation and melt intercalation.Properties and structure of the composites were investigated by using XRD,TG ...Phenolic resin/montmorillonite intercalation composites were prepared by using the methods of pressing intercalation and melt intercalation.Properties and structure of the composites were investigated by using XRD,TG and test of softening point.It is indicated that both the pressing intercalation and melt intercalation can be used to prepare the phenolic resin/organo-montmorillonite intercalation nanocomposites.Compared with phenolic resin,the intercalation nanocomposites have better heat-resistance,higher decomposition temperatures and less thermal weight-loss.However,these two intercalation methods have different effects on the softening point of the intercalation nanocomposites.Pressing intercalation almost does not affect the softening point of the intercalation nanocomposites,while melt intercalation significantly increases the softening point of the intercalation nanocomposites, probably due to the chemical actions happening in the process of melt intercalation.展开更多
A precondition for correctly analyzing the stability of a slope and designing its bracing structure is to study and determine the influence of excavation blasting on the properties of weak intercalation in the layered...A precondition for correctly analyzing the stability of a slope and designing its bracing structure is to study and determine the influence of excavation blasting on the properties of weak intercalation in the layered rock slope. On the basis of in-situ stratification-cracking blasting tests, the properties of weak intercalation were investigated using the LS-DYNA3D program. The displacement distribution and compactness of weak intercalation at different positions away from the charge center and their various laws are discussed. The critical displacement of stratification-cracking (0.1 mm) was obtained, and an approximate expression of compactness were deduced. Furthermore, through the simulation of a layered rock blasting under the same geological conditions, the stratification-cracking effect of deep-hole blasting on the properties of weak intercalation was compared with that of short-hole blasting, and the influencing differences, in addition to their causes, were analyzed. The results indicated that the blasting cavity of weak intercalation in short-hole blasting with a radius of 40 mm was nearly a circle, whose radius was about 28.7 cm; whereas in deep-hole blasting with a radius of 150 mm, the shape of the blasting cavity was different from that in short-hole blasting, the radius of the cavity behind the charge (89.1 cm) was further smaller than those of the other three (138.7 cm), and there were sharp crinkles on the surface of weak intercalation. When the distance from the charge center (DCC) was less than 40 and 150 cm in short-hole and deep-hole blasting, respectively, the displacement of weak intercalation was reduced remarkably with the increase in DCC.展开更多
Superfine graphite powder was prepared by ball-milling exfoliated graphite containing anhydrous CuCl2 in planetary ball milling systems. Nano-scale CuCl2 graphite intercalation compounds were synthesized by heating a ...Superfine graphite powder was prepared by ball-milling exfoliated graphite containing anhydrous CuCl2 in planetary ball milling systems. Nano-scale CuCl2 graphite intercalation compounds were synthesized by heating a mixture of anhydrous CuCl2 and graphite nanosheets. Scanning electron microscopy, energy-dispersive X-ray spectroscopy and high-resolution transmission electron microscopy were performed to characterize the microstructures of stage-1 nano-scale CuCl2 graphite intercalation compounds. The structure and components of the domain wall and core in the nano-scale CuCl2 graphite intercalation compounds are described. The results show that the content of CuCl2 in the mixture plays a crucial role in the size of the nano-scale CuCl2 graphite intercalation compound.展开更多
基金the National Nature Science Foundation of China (Nos. 50771046 and 20373016) the Natural Science Foundation of Guangdong Province (No. 05200534)the Key Projects of Guangdong Province and Guangzhou City, China (Nos. 2006A10704003 and 2006Z3-D2031)
文摘A tin film of 320 nm in thickness on Cu foil and its composite film with graphite of-50 nm in thickness on it were fabricated by magnetron sputtering. The surface morphology, composition, surface distributions of alloy elements, and lithium intercalation/de-intercalation behaviors of the fabricated films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), electron probe microanalyzer (EPMA), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma atomic emission spectrometry (ICP), cyclic voltammetry (CV), and galvanostatic charge/discharge (GC) measurements. It is found that the lithium intercalation/de-intercalation behavior of the Sn film can be significantly improved by its composite with graphite. With cycling, the discharge capacity of the Sn film without composite changes from 570 mAh/g of the 2nd cycle to 270 mAh/g of the 20th cycle, and its efficiency for the discharge and charge is between 90% and 95%. Nevertheless, the discharge capacity of the composite Sn/C film changes from 575 mAh/g of the 2nd cycle to 515 mAh/g of the 20th cycle, and its efficiency for the discharge and charge is between 95% and 100%. The performance improvement of tin by its composite with graphite is ascribed to the retardation of the bulk tin cracking from volume change during lithium intercalation and de-intercalation, which leads to the pulverization of tin.
文摘V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve the stability,organic small molecule choline chloride intercalation is used to expand the spacing of the vanadium pentoxide layers and increase the cycling stability.Therefore,we consider the introduction of Sr^(2+)to cointercalate with choline chloride.Here,we synthes-ized vanadium pentoxide cointercalated with Sr^(2+)and choline ions(Ch^(+))via a simple hydrothermal method.The electro-chemical performance shows an enhanced cathode capacitance contribution of Sr&Ch-V_(2)O_(5),with a discharge capacity of 526 mAh·g^(-1)at 0.1 A·g^(-1)and a retention rate of 78.9%after 2000 cycles at 5 A·g^(-1).This work offers a novel strategy for the design of organic‒inorganic hybrid materials for use as cathodes in aqueous zinc-ion batteries.
文摘Intercalation catalysis research involves inserting metal ions,molecules,or ionic liquids into the layered structure of catalysts to adjust their electronic structure and surface properties,thereby optimizing catalytic reaction efficiency and selectivity[1–3].This technique has achieved significant progress in areas such as electrocatalysis,catalytic cracking,and energy conversion,especially in reactions like hydrogen generation,oxygen reduction,nitrogen reduction,and carbon dioxide reduction[4–6].Intercalation catalysis can enhance catalyst activity and selectivity,but challenges remain regarding stability,reusability,and industrial application.Future research will focus on developing new intercalation materials,optimizing catalyst design,and exploring their potential applications in complex environments[7].
基金financial support from the National Natural Science Foundation of China(52372173,52072034)。
文摘Direct electrolysis of seawater offers a transformative technology for sustainable hydrogen production,circumventing the constraint of freshwater scarcity.However,the serious electrode corrosion and competitive chloride oxidation reactions make oxygen evolution reaction(OER)in seawater extremely challenging.Herein,the low-cost and scalable CoFe layered double hydroxides with Cl^(-)intercalation and decorated with Ce(OH)_(3)(named as CoFe-Cl^(-)/Ce(OH)_(3))catalyst is synthesized via rapid electrodeposition under ambient conditions,which is quickly reconstructed into a CeO_(2)decorated and Cl^(-)intercalated CoFeOOH(CoFeOOH-Cl^(-)/CeO_(2))during OER.Theoretical investigation reveals that Cl^(-)intercalation weakens the adsorption ability of Cl^(-)on Co/Fe atoms and hinders unfavorable coupling with chloride,thereby preventing the chlorine corrosion process and enhancing catalytic stability and activity.The CeO_(2)with hard Lewis acidity preferentially binds to OH-with harder Lewis base to ensure the OH-rich microenvironment around catalyst even under high current operating conditions,thus further enhancing stability and improving OER activity.The functionalized CoFe-Cl^(-)/Ce(OH)_(3)delivers 1000 mA cm^(-2)current density at only 329 mV overpotential with excellent stability for 1000 h under alkaline seawater.Electrochemical experiments elucidate the OER catalytic mechanism in which CeO_(2)serves as a co-catalyst for enriching OH-and CoFeOOH-Cl^(-)is the active species.Our work is a substantial step towards achieving massive and sustainable production of hydrogen fuel from immense seawater.
基金financially supported by the National Natural Science Foundation of China(Nos.22435005,22193042,21921001,52202194,22305105,22201284)the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(No.ZDBSLY-SLH024)。
文摘Two-dimensional(2D)organic-inorganic hybrid perovskites(OIHPs)have been developed as promising candidates for photodetection,owing to their excellent semiconducting features and structural tunability.However,as an important parameter for photodetection,the photoresponsive range of 2D OIHPs is usually modulated by finite metal-halide combinations,constraining their further development.The emerging aromatic amine-based alternating-cations-interlayered(A-ACI)hybrid perovskites that exhibit excellent charge transport and additional interlayered structural designability,provide an extra solution for achieving ideal photoresponsive range.Herein,for the first time,the photoresponsive range is successfully broadened in A-ACI hybrid perovskites(NMA)_(4)(FA)_(2)Pb_(3)Br_(12)(2)remolding from(NMA)_(4)(MA)_(2)Pb_(3)Br_(12)(1)(NMA=N-methylbenzylaminium,FA=formamidinium and MA=methylammonium).Particularly,1 and 2adopt an unprecedented configuration that NMA and MA/FA are alternately arranged in the interlayer in a 4:2 manner.Importantly,2 exhibits a narrower bandgap than 1,which can be ascribed to the lowlying conduct band composed of intercalation FAπ*orbitals.Meanwhile,2 possesses a shorter interlayer distance and flatter inorganic skeleton,synergistically facilitating the wider photo-absorption range and further endowing a broadening photoresponsive range(70 nm).This research not only enriches the perovskite family but also provides insights into structure-property relationships.
基金supported by the National Key R&D Program of China(2022YFA1203400)the National Natural Science Foundation of China(W2441009)。
文摘Magnesium-ion batteries hold promise as future energy storage solutions,yet current Mg cathodes are challenged by low voltage and specific capacity.Herein,we present an AI-driven workflow for discovering high-performance Mg cathode materials.Utilizing the common characteristics of various ionic intercalation-type electrodes,we design and train a Crystal Graph Convolutional Neural Network model that can accurately predict electrode voltages for various ions with mean absolute errors(MAE)between0.25 and 0.33 V.By deploying the trained model to stable Mg compounds from Materials Project and GNoME AI dataset,we identify 160 high voltage structures out of 15,308 candidates with voltages above3.0 V and volumetric capacity over 800 mA h/cm^(3).We further train a precise NequIP model to facilitate accurate and rapid simulations of Mg ionic conductivity.From the 160 high voltage structures,the machine learning molecular dynamics simulations have selected 23 cathode materials with both high energy density and high ionic conductivity.This Al-driven workflow dramatically boosts the efficiency and precision of material discovery for multivalent ion batteries,paving the way for advanced Mg battery development.
基金supported by the National Key Research and Development Program of China(Grant Nos.2022YFA1402404 and 2023YFA1406304)the National Natural Science Foundation of China(Grant Nos.92161201,T2221003,12104221,12104220,12274208,12025404,12004174,91961101,T2394473,62274085,12374043,and U2032208)+1 种基金the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20230079,BK20243013,and BK20233001)the Fundamental Research Funds for the Central Universities(Grant Nos.020414380192 and 2024300432).
文摘MnBi_(2)Te_(4),which is emerging as an intrinsic antiferromagnetic(AFM)topological insulator,provides a unique platform to investigate the interplay between magnetism and topology.Modulating its magnetic properties enables the observation of exotic quantum phenomena such as the quantum anomalous Hall effect,axion insulator states,and Majorana fermions.While the intercalation of Bi_(2)Te_(3)can tune its magnetism,synthesizing pure-phase MnBi_(2)Te_(4)with uniform Bi_(2)Te_(3)intercalation remains challenging,and the fixed interlayer spacing of Bi_(2)Te_(3)limits magnetic coupling tunability.Here,we utilize electrochemical organic molecule intercalation to expand the van der Waals gap of MnBi_(2)Te_(4)and modulate its magnetic properties.Through x-ray diffraction(XRD)characterizations,we confirm that the interlayer spacing of MnBi_(2)Te_(4)is expanded from 13.6°A to 30.5°A and 61.0°A by intercalating quaternary ammonium cations(THA^(+)and CTA^(+)),respectively.The THA-MnBi_(2)Te_(4)exhibits dual complex magnetic behavior,combining AFM ordering with a Neel temperature(T_(N))of 12 K and a small ferromagnetic hysteresis loop at 2 K.The CTA-MnBi_(2)Te_(4)shows robust ferromagnetism,with a Curie point(T_(C))of 15 K,similar to that of the MnBi_(2)Te_(4)monolayer.These results demonstrate that remarkable changes in the magnetic properties of MnBi_(2)Te_(4)can be achieved via electrochemical intercalation,providing new insights into manipulating magnetism in layered magnetic materials.
基金financially supported by the National Natural Science Foundation of China(No.22179113)the Fundamental Research Funds for the Central Universities(Nos.20720230028 and 20720210045)+1 种基金the Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM)(No.HRTP-2022-19)the XMU Training Program of Innovation and Entrepreneurship for Undergraduates(No.2021Y1089)。
文摘Developing anode materials with high specific/volumetric capacities,high-rate capability,long-term cycles and low cost is significant for advanced sodium-ion storage.Herein,we report the hybrid TiO_(2)/graphite(TiO_(2)/G)anodes for fast(dis)charging sodium-ion storage.Taking advantage of the rapid pseudocapacitive surface-redox on anatase TiO_(2)nanoparticles(NPs)and fast[Na(diglyme)_(x)]^(+)co-intercalation into graphite,the hybrid anodes display excellent rate capabilities.Additionally,the TiO_(2)NPs are able to fill into the interspaces among graphite flakes and the graphite provides continuous electron pathways,which largely boosts the volumetric capacities and rate performance.
基金supported by the National Natural Science Foundation of China(No.51802163)the Natural Science Foundation of Henan Province of China(No.222300420252)the Natural Science Foundation of Henan Department of Education(No.20A480004).
文摘Orthorhombic Nb_(2)O_(5)(T-Nb_(2)O_(5))is attractive for fast-charging Li-ion batteries,but it is still hard to realize rapid charge transfer kinetics for Li-ion storage.Herein,F-doped T-Nb_(2)O_(5) microflowers(F-Nb_(2)O_(5))are rationally synthesized through topotactic conversion.Specifically,F-Nb_(2)O_(5) are assembled by single-crystal nanoflakes with nearly 97%exposed(100)facet,which maximizes the exposure of the feasible Li^(+)transport pathways along loosely packed 4g atomic layers to the electrolytes,thus effectively enhancing the Li^(+)-intercalation performance.Besides,the band gap of F-Nb_(2)O_(5) is reduced to 2.87 eV due to the doping of F atoms,leading to enhanced electrical conductivity.The synergetic effects between tailored exposed crystal facets,F-doping,and ultrathin building blocks,speed up the Li^(+)/electron transfer kinetics and improve the pseudocapacitive properties of F-Nb_(2)O_(5).Therefore,F-Nb_(2)O_(5) exhibit superior rate capability(210.8 and 164.9 mAh g^(-1) at 1 and 10 C,respectively)and good long-term 10 C cycling performance(132.7 mAh g^(-1) after 1500 cycles).
基金financially supported by the National Natural Science Foundation of China(No.22279122)Shenzhen Science and Technology Program(No.JCYJ20220530162402005)+2 种基金the Research on High Power Flexible Battery in All Sea Depth(2020-XXXX-XX-246-00)the Research Fund Program of Hubei Key Laboratory of Resources and EcoEnvironment Geology(No.HBREGKFJJ-202314)and the Fundamental Research Funds for the Central Universities,South-Central Minzu University(No.CZQ21013)。
文摘Metallic zinc is an ideal anode material owing to its high theoretical capacity(819 mAh·g^(-1)),ecofriendliness,low cost and high safety,which have driven fast development of Zn-ion batteries(ZIBs).However,the practical application of current ZIBs is significantly restricted by irregular dendrite growth of zinc anode and the low working voltage(usually<2 V)of cathode materials.Herein,we report a high-voltage Zn-based dualion battery(DIB),which is constructed by a graphite cathode,a Zn anode,and 3 M LiPF_(6)in the ethyl methyl carbonate(EMC)electrolyte.Under the corrosion interaction of Li^(+)ions,Zn^(2+)can be easily dissolved from Zn anode into the electrolyte to enable dendrite-free Zn^(2+)plating/stripping at the anode.Moreover,an aqueous carboxymethyl cellulose(CMC)binder is employed to generate a robust cathode electrolyte interface(CEI)layer on the graphite cathode,which renders ultrafast PF_(6)^(-)-de-/intercalation into graphite.The resultant Zn-graphite DIB operates stably at a high cut off voltage of 3.2 V,corresponding to an average output voltage of 2.2 V.After 9000cycles at 5C,the high capacity retention of 95.9% can be achieved with~100% Coulomb efficiency.Based on the mass of cathode material,our Zn-graphite battery exhibits ultrafast rate capability(60 C,a discharge time of 44 s)and high energy/power densities(208 Wh·kg^(-1)at 214 W·kg^(-1);142 Wh·kg^(-1)at 8692 W·kg^(-1)),which holds great promise for large-scale energy storage.
基金National Natural Science Foundation of China,Grant/Award Number:22309062Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2022A1515110052Jihua Laboratory,Grant/Award Numbers:X200191TL200,X220301XS220。
文摘The typical metal chloride-graphite intercalation compounds(MC-GICs)inherit intercalation capacity,high charge conductivity,and high tap density from graphite,and these are considered as one of the promising alternatives of graphite anode in rechargeable metal-ion batteries(MIBs).Notably,the special interlayer decoupling effects and the introduction of extra conversion capacity by metal chloride could greatly break the capacity limitation of graphite anodes and achieve higher energy density in MIBs.The optimization of both graphite host and metal chloride species with specific structures endows MC-GICs with design feasibility for different application requirements of different MIBs,such as several times the actual capacity compared to graphite anodes,rapid migration of large carriers,and other properties.Herein,a brief review has been provided with the latest understanding of conductivity characteristics and energy storage mechanisms of MC-GICs and their interesting performance features of full potential application in rechargeable MIBs.Based on the existing research of MC-GICs,necessary improvements and prospects in the near future have been put forward.
基金the financial support from the National Natural Science Foundation of China(No.22178307)China Southern Power Grid(Grant Nos.0470002022030103HX00002-01).
文摘The poor electronic conductivity of metal-organic framework(MOF)materials hinders their direct application in the field of electrocatalysis in fuel cells.Herein,we proposed a strategy of embedding carbon nanotubes(CNTs)during the growth process of MOF crystals,synthesizing a metalloporphyrin-based MOF catalyst TCPPCo-MOF-CNT with a unique CNT-intercalated MOF structure.Physical characterization revealed that the CNTs enhance the overall conductivity while retaining the original characteristics of the MOF and metalloporphyrin.Simultaneously,the insertion of CNTs generated adequate mesopores and created a hierarchical porous structure that enhances mass transfer efficiency.X-ray photoelectron spectroscopic analysis confirmed that the C atom in CNT changed the electron cloud density on the catalytic active center Co,optimizing the electronic structure.Consequently,the E_(1/2) of the TCPPCo-MOF-CNT catalyst under neutral conditions reached 0.77 V(vs.RHE),outperforming the catalyst without CNTs.When the TCPPCo-MOF-CNT was employed as the cathode catalyst in assembling microbial fuel cells(MFCs)with Nafion-117 as the proton exchange membrane,the maxi-mum power density of MFCs reached approximately 500 mW·m^(-2).
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2020R1A6A1A03043435 and NRF-2021R1A2C1008798).
文摘Two-dimensional MXenes are renowned for their remarkable electrical conductivity and electrochemical activity making them highly promising for electrode applications.However,the restacking of MXene nanosheets impairs their functionality by reducing active sites and obstructing ionic transport.This study presents a facile synthesis approach for nickel-intercalated MXene,designed to enhance surface reactivity,avoid restacking,and achieve improved electrochemical performance.Electrochemical studies revealed that the nickel-MXene hybrid showed better cycling stability,retaining 83.7%of its capacity after 10000 cycles and attaining an energy density of 26 Wh kg^(-1) at a power density of 1872Wkg^(-1).It also exhibited overpotentials of 109 and 482 mV at 10 and 100 mA cm^(-2),respectively,in the hydrogen evolution reaction.To predict the structural and electrical alterations caused by nickel inclusion,as well as to understand the intercalation mechanism,spin-polarized density functional theory calculations were carried out.The theoretical results showed an improved carrier concentration for nickel-MXene.Nickel-MXene possessed superior electronic characteristics and surplus active sites with hexagonal closed-packed(hcp)edge sites,which enhanced electrochemical properties.Our results demonstrate that nickel intercalation prevents the restacking of MXene but also significantly improves their electrochemical characteristics,making them ideal for energy storage and catalytic applications.
基金Project supported by the National Natural Science Foundation of China(Grant No.12274440)the National Key R&D Program of China(Grant No.2022YFA1403903)+1 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB33010100)the Fund of the Synergetic Extreme Condition User Facility(SECUF)。
文摘The interaction between charge and spin degrees of freedom has always been the central issue of condensed matter physics,and transition metal dichalcogenides(TMDs)provide an ideal platform to study it benefiting from their highly tunable properties.In this article,the influence of Fe intercalation in NbSe_(2)was elaborately investigated using a combination of techniques.Magnetic studies have shown that the insertion of Fe atoms induces an antiferromagnetic state in which the easy axis aligns out of the plane.The sign reversal of the magnetoresistance across the Neel temperature can be satisfactorily explained by the moderate interaction between electrons and local spins.The Hall and Seebeck measurements reveal a multi-band nature,and the contribution of various phonon scattering processes is discussed based on the thermal conductivity and specific heat data.
基金supported by the National Natural Science Foundation of China(22075196,U22A20418,21878204)the Research Project Supported by Shanxi Scholarship Council of China(2022-050).
文摘Transition metal-based compounds can serve as pre-catalysts to obtain genuine oxygen evolution reaction(OER)electrocatalysts in the form of oxyhydroxides through electrochemical activation.However,the role and existence form of leached oxygen anions are still controversial.Herein,we selected iron selenite-wrapped hydrated nickel molybdate(denoted as NiMoO/FeSeO)as a pre-catalyst to study the oxyanion effect.It is surprising to find that SeO_(2)-exists in the catalyst in the form of intercalation,which is different from previous studies that suggest that anions are doped with residual elements after electrochemical activation,or adsorbed on the catalyst surface.The experiment and theoretical calculations show that the existence of SeO_(4)^(2-)intercalation effectively adjusts the electronic structure of NiFeOOH,promotes intramolecular electron transfer and O-O release,and thus lowers the reaction energy barrier.As expected,the synthesized NiFeOOH-SeO only needs 202 and 285 mV to attain 100 and 1000 mA cm^(-2)in 1 M KOH.Further,the anion exchange membrane water electrolyzer(AEMWE)consisting of NiFeOOHSeO anode and Pt/C cathode can reach 1 A cm^(-2)at 1.70 V and no significant attenuation within 300 h.Our findings provide insights into the mechanism,by which the intercalated oxyanions enhance the OER performance of NiFeOOH,thereby facilitating large-scale hydrogen production through AEMWE.
基金supported by the International Science & Technology Cooperation Program of China(2010DFB63680)the National Natural Science Foundation of China(21376220)Zhejiang Provincial Natural Science Foundation of China(LY16B060009,LY12B03008)~~
文摘Highly dispersed tungsten carbide(WC) nanoparticles(NPs) sandwiched between few-layer reduced graphene oxide(RGO) have been successfully synthesized by using thiourea as an anchoring and inducing reagent.The metatungstate ion,[H2W(12)O(40)]^6-,is assembled on thiourea-modified graphene oxide(GO) by an impregnation method.The WC NPs,with a mean diameter of 1.5 nm,are obtained through a process whereby ammonium metatungstate first turns to WS2,which then forms an intercalation compound with RGO before growing,in situ,to WC NPs.The Pt/WC-RGO electrocatalysts are fabricated by a microwave-assisted method.The intimate contacts between Pt,WC,and RGO are confirmed by X-ray diffraction,scanning electron microscope,transmission electron microscope,and Raman spectroscopy.For methanol oxidation,the Pt/WC-RGO electrocatalyst exhibited an electrochemical surface area value of 246.1 m^2/g Pt and a peak current density of1364.7 mA/mg Pt,which are,respectively,3.66 and 4.77 times greater than those of commercial Pt/C electrocatalyst(67.2 m^2/g Pt,286.0 mA/mg Pt).The excellent CO-poisoning resistance and long-term stability of the electrocatalyst are also evidenced by CO stripping,chronoamperometry,and accelerated durability testing.Because Pt/WC-RGO has higher catalytic activity compared with that of commercial Pt/C,as a result of its intercalated structure and synergistic effect,less Pt will be required for the same performance,which in turn will reduce the cost of the fuel cell.The present method is facile,efficient,and scalable for mass production of the nanomaterials.
基金supported by both the Technology Innovation Program(20004958,Development of ultra-high performance supercapacitor and high power module)funded by the Ministry of Trade,Industry and Energy(MOTIE)the R&D Convergence Program(CAP-15-02-KBSI)of the National Research Council of Science&Technology,Republic of Korea。
文摘With the development of stable alkali metal anodes,V_(2)O_(5) is gaining traction as a cathode material due to its high theoretical capacity and the ability to intercalate Li,Na and K ions.Herein,we report a method for synthesizing structured orthorhombic V_(2)O_(5) microspheres and investigate Li intercalation/deintercalation into this material.For industry adoption,the electrochemical behavior of V_(2)O_(5) as well as structural and phase transformation attributing to Li intercalation reaction must be further investigated.Our synthesized V_(2)O_(5) microspheres consisted of small primary particles that were strongly joined together and exhibited good cycle stability and rate capability,triggered by reversible volume change and rapid Li ion diffusion.In addition,the reversibility of phase transformation(a,e,d,c and xLixV_(2)O_(5))and valence state evolution(5+,4+,and 3.5+)during intercalation/de-intercalation were studied via in-situ X-ray powder diffraction and X-ray absorption near edge structure analyses.
文摘Phenolic resin/montmorillonite intercalation composites were prepared by using the methods of pressing intercalation and melt intercalation.Properties and structure of the composites were investigated by using XRD,TG and test of softening point.It is indicated that both the pressing intercalation and melt intercalation can be used to prepare the phenolic resin/organo-montmorillonite intercalation nanocomposites.Compared with phenolic resin,the intercalation nanocomposites have better heat-resistance,higher decomposition temperatures and less thermal weight-loss.However,these two intercalation methods have different effects on the softening point of the intercalation nanocomposites.Pressing intercalation almost does not affect the softening point of the intercalation nanocomposites,while melt intercalation significantly increases the softening point of the intercalation nanocomposites, probably due to the chemical actions happening in the process of melt intercalation.
基金supported by the National Natural Science Foundation of China (No.50574076 and No.50838006)
文摘A precondition for correctly analyzing the stability of a slope and designing its bracing structure is to study and determine the influence of excavation blasting on the properties of weak intercalation in the layered rock slope. On the basis of in-situ stratification-cracking blasting tests, the properties of weak intercalation were investigated using the LS-DYNA3D program. The displacement distribution and compactness of weak intercalation at different positions away from the charge center and their various laws are discussed. The critical displacement of stratification-cracking (0.1 mm) was obtained, and an approximate expression of compactness were deduced. Furthermore, through the simulation of a layered rock blasting under the same geological conditions, the stratification-cracking effect of deep-hole blasting on the properties of weak intercalation was compared with that of short-hole blasting, and the influencing differences, in addition to their causes, were analyzed. The results indicated that the blasting cavity of weak intercalation in short-hole blasting with a radius of 40 mm was nearly a circle, whose radius was about 28.7 cm; whereas in deep-hole blasting with a radius of 150 mm, the shape of the blasting cavity was different from that in short-hole blasting, the radius of the cavity behind the charge (89.1 cm) was further smaller than those of the other three (138.7 cm), and there were sharp crinkles on the surface of weak intercalation. When the distance from the charge center (DCC) was less than 40 and 150 cm in short-hole and deep-hole blasting, respectively, the displacement of weak intercalation was reduced remarkably with the increase in DCC.
基金the National Natural Science Fund(50774071) ;the Natural Science Foundation of Hubei Province(2004ABA090).
文摘Superfine graphite powder was prepared by ball-milling exfoliated graphite containing anhydrous CuCl2 in planetary ball milling systems. Nano-scale CuCl2 graphite intercalation compounds were synthesized by heating a mixture of anhydrous CuCl2 and graphite nanosheets. Scanning electron microscopy, energy-dispersive X-ray spectroscopy and high-resolution transmission electron microscopy were performed to characterize the microstructures of stage-1 nano-scale CuCl2 graphite intercalation compounds. The structure and components of the domain wall and core in the nano-scale CuCl2 graphite intercalation compounds are described. The results show that the content of CuCl2 in the mixture plays a crucial role in the size of the nano-scale CuCl2 graphite intercalation compound.