Available onlineSilicon monoxide(SiO)is a promising anode material fo r lithium-ion batteries(LIBs)due to its high theoretical specific capacity(~2400 mAh/g),low working potential(<0.5 V vs.Li^+/Li),low cost,easy s...Available onlineSilicon monoxide(SiO)is a promising anode material fo r lithium-ion batteries(LIBs)due to its high theoretical specific capacity(~2400 mAh/g),low working potential(<0.5 V vs.Li^+/Li),low cost,easy synthesis,nontoxicity,abundant natural source and smaller volume expansion than Si.However,low intrinsic electrical conductivity,low initial Coulombic efficiency(ICE)and inevitable volume expansion(~200%)impede its practical application.Here we fabricate SiO/wrinkled MXene composite(SiO-WM)by an electrostatic self-assembly method.Importantly,this method is simple,scalable and taking into account all the issues of SiO.As a result,the SiO-WM exhibits imp roved rate capability,cycling performance and ICE than bare SiO.展开更多
Constructing electrode materials with large capacity and good conductivity is an effective approach to improve the capacitor performance of asymmetric supercapacitors(ASCs).In this paper,ZnCo_(2)S_(4)core-shell nanosp...Constructing electrode materials with large capacity and good conductivity is an effective approach to improve the capacitor performance of asymmetric supercapacitors(ASCs).In this paper,ZnCo_(2)S_(4)core-shell nanospheres are constructed by two-step hydrothermal method.In order to improve the chemical activity of ZnCo_(2)S_(4),ZnCo_(2)S_(4)is activated using cetyltrimethylammonium bromide(CTAB).Then,MXene nanosheets are fixed on the surface of ZnCo_(2)S_(4)by electrostatic selfassembly method to improve the specific surface area of ZnCo_(2)S_(4)and MXene-wrapped ZnCo_(2)S_(4)composite is prepared in this work.Owing to the synergy effect between MXene nanosheets and ZnCo_(2)S_(4)core-shell nanospheres,the as-prepared composite displays fast ion transfer rate and charge/discharge process.The capacity of the MXenewrapped ZnCo_(2)S_(4)composite can reach 1072 F·g^(-1),which is far larger than that of ZnCo_(2)S_(4)(407 F·g^(-1))at 1 A·g^(-1).An ASC device is assembled,which delivers 1.7 V potential window and superior cyclic stability(95.41%capacitance retention).Furthermore,energy density of this device is up to 30.46 Wh·kg^(-1)at a power density of850 W·kg^(-1).The above results demonstrate that MXenewrapped ZnCo_(2)S_(4)composite has great application prospects in electrochemical energy storage field.展开更多
Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spect...Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spectroscopy （FT-IR） and scanning electron microscopy （SEM）. Methyl orange was used to estimate the photocatalytic activity of the materials. The effects of the calcination temperature and silane dosage on the photocatalytic activity of the samples were investigated. The experimental results show that the bentonite facilitates the formation of anatase and restrains the transformation of anatase to rutile. Part of nano-size TiO2 particles insert into the galleries of bentonite. The photocatalysts exhibit a synergistic effect of adsorption and photocatalysis on methyl orange. Photocatalysts prepared by ESAM method exhibit higher photocatalytic activity and better recycle ability than those of the traditional method.展开更多
Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (...Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (ESA) method. The whole self-assemble process, the function of surfactant and the effect of TiO_2 slurry′s concentration to the self-assemble were discussed. The isoelectric point of TiO_2 slurry measured by experiment is 6.8. The results show that whatever the concentration of the TiO_2 dispersion, a flat and compact adsorbed monolayer on the optic fiber can be built in a stable dispersion at lower pH. There is a adsorbed equilibrium on the substrate (fiber)/solution interface when enough time of incubation is given. A rough and loosen adsorbed layer is formed on the fiber surface by immersed the substrate in a high pH dispersion (pH>10) because the presence of hydroxyl on particle surface. Film thickness can be controlled by controlling the number of layers in the film.展开更多
Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin f...Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin films on si/icon and quartz substrates. The paniculate thin films were characterized by UV-vis spea-troscopy, surface, enhanced Raman scattering, atomic force microscopy and resistivity measurements. Due to the interparticle coupling between individual gold particles, an obvious collective particle plasmon resonance was ob-served on UV-vis spectra , and the particulate thin films exhibited a strong SERS effect. For multilayer thin films with a high particle coverage on substrates , resistivity of the order of 10-4 Ω·cm was yielded.展开更多
Aqueous zinc ion batteries have become highly favored energy storage devices owing to low cost and environmental friendliness.Vanadium oxide,as one of the potential cathodes for AZIBs,is plagued by several unfavorable...Aqueous zinc ion batteries have become highly favored energy storage devices owing to low cost and environmental friendliness.Vanadium oxide,as one of the potential cathodes for AZIBs,is plagued by several unfavorable elements including unsatisfactory conductivity and vanadium dissolution in the electrolyte.Herein,an electrostatic self-assembly strategy is proposed to introduce conductive dielectric Ti_(3)C_(2)T_(x)MXene nanoplates into V_(2)O_(5)·4VO_(2)nanoribbons,where V_(2)O_(5)·4VO_(2)/MXene composites(denoted as VM2)are simply obtained by magnetic stirring combined with ultrasonic method at room temperature.The successful introduction of MXene with high electrical conductivity not only endows faster V_(2)O_(5)·4VO_(2)electron/ion transfer,but also acts as a"baffle"to inhibit vanadium dissolution.Benefiting from the above advantages,paired with a zinc metal anode,VM2 cathode exhibits impressive performance metrics of 328.7 mAh·g^(−1)at 0.1 A·g^(−1),95.8%capacity retention after 1000 cycles,and 142.9 mAh·g^(−1)at a current density of 20 A·g^(−1).This work provides a viable reference for the development of high-performance AZIBs.展开更多
Low patency ratio of small-diameter vascular grafts remains a major challenge due to the occurrence of thrombosis formation and intimal hyperplasia after transplantation.Although developing the functional coating with...Low patency ratio of small-diameter vascular grafts remains a major challenge due to the occurrence of thrombosis formation and intimal hyperplasia after transplantation.Although developing the functional coating with release of bioactive molecules on the surface of small-diameter vascular grafts are reported as an effective strategy to improve their patency ratios,it is still difficult for current functional coatings cooperating with spatiotemporal control of bioactive molecules release to mimic the sequential requirements for antithrombogenicity and endothelialization.Herein,on basis of 3D-printed polyelectrolyte-based vascular grafts,a biologically inspired release system with sequential release in spatiotemporal coordination of dual molecules through an electrostatic self-assembly was first described.A series of tubes with tunable diameters were initially fabricated by a coaxial extrusion printing method with customized nozzles,in which a polyelectrolyte ink containing of ε-polylysine and sodium alginate was used.Further,dual bioactive molecules,heparin with negative charges and Tyr-Ile-Gly-Ser-Arg(YIGSR)peptide with positive charges were layer-by-layer assembled onto the surface of these 3D-printed tubes.Due to the electrostatic interaction,the sequential release of heparin and YIGSR was demonstrated and could construct a dynamic microenvironment that was thus conducive to the antithrombogenicity and endothelialization.This study opens a new avenue to fabricate a small-diameter vascular graft with a biologically inspired release system based on electrostatic interaction,revealing a huge potential for development of small-diameter artificial vascular grafts with good patency.展开更多
High-performance epoxy(EP)composites with excellent thermal conductivity and dielectric properties have attracted increasing attention for effective thermal management.In this work,three-dimensional(3D)structural func...High-performance epoxy(EP)composites with excellent thermal conductivity and dielectric properties have attracted increasing attention for effective thermal management.In this work,three-dimensional(3D)structural functional fillers were prepared by an electrostatic self-assembly approach.The negatively charged carbon nanotubes(nCNTs)prepared by carboxylation on the surface of CNTs were attached to the positively charged boron nitride(pBN)to form the 3D pBN@nCNTs functional fillers.The morphological characterizations of the formed 3D pBN@nCNTs fillers and epoxy composites were established,illustrating that nCNTs were linearly overlapped between the BN sheets,thus forming a 3D heat conduction network in the epoxy matrix.The synergistic effect of pBN with nCNTs on the enhancement of thermal conductivity and dielectric properties of composites was systematically studied.The experimental results demonstrated that the thermal conductivity of pBN@nCNTs/EP composites could reach 1.986 W m1K1 with the loading of 50 wt%fillers at 10:1 mass ratio of pBN:nCNTs,which is 464%and 124%higher than that of pure EP and BN/EP,respectively.Simultaneously,the dielectric permittivity was successfully increased to 15.14.Moreover,the thermal stability of the composites was synchronously enhanced.This study provides a facile path to fabricate thermosetting polymer composites with high thermal conductivity and dielectric properties.展开更多
Al/NH_(4)CoF_(3)-Φ(Φ=0.5,1.0,1.5,2.0,and 3.0)binary composites and Al-NH_(4)CoF_(3)@P(VDF-HFP)ternary composites are fabricated via ultrasonication-assisted blending and electrostatic spraying.The effect of equivale...Al/NH_(4)CoF_(3)-Φ(Φ=0.5,1.0,1.5,2.0,and 3.0)binary composites and Al-NH_(4)CoF_(3)@P(VDF-HFP)ternary composites are fabricated via ultrasonication-assisted blending and electrostatic spraying.The effect of equivalence ratio(Φ)on the reaction properties is systematically investigated in the binary Al/NH_(4)CoF_(3)system.For ternary systems,electrostatic spraying allows both components to be efficiently encapsulated by P(VDF-HFP)and to achieve structural stabilization and enhanced reactivity through synergistic interfacial interactions.Morphological analysis using SEM/TEM revealed that P(VDF-HFP)formed a protective layer on Al and NH_(4)CoF_(3)particles,improving dispersion,hydrophobicity(water contact angle increased by 80.5%compared to physically mixed composites),and corrosion resistance.Thermal decomposition of NH_(4)CoF_(3)occurred at 265℃,releasing NH_(3)and HF,which triggered exothermic reactions with Al.The ternary composites exhibited a narrowed main reaction temperature range and concentrated heat release,attributed to improved interfacial contact and polymer decomposition.Combustion tests demonstrated that Al-NH_(4)CoF_(3)@P(VDF-HFP)achieved self-sustaining combustion.In addition,a simple validation was done by replacing the Al component in the aluminium-containing propellant,demonstrating its potential application in the propellant field.This work establishes a novel strategy for designing stable,high-energy composites with potential applications in advanced propulsion systems.展开更多
Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered asse...Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered assembly of graphene oxide(GO)nanosheets in solution films can be realized to obtain the high-quality and large-area reduced GO(rGO)films.The key to the success of this process primarily lies in the control of GO solution shear force direction with array capillaries,achieving oriented arrangement of GO nanosheets in the solution film.Secondly,the control of GO nanosheet concentration and solution viscosity during solvent evaporation of solution film is key to achieve the ordered and disordered assembly of GO,featuring the smooth and wrinkled structure rGO films,respectively.Subsequently,the resultant smooth rGO film with ordered assembly exhibits excellent thermal conductivity and electronic conductivity(over 1800 S·cm-1).Meanwhile,the wrinkled rGO film with disordered assembly can be used as a coating layer on Al current collectors,demonstrating anticorrosion properties and enhanced material adhesive stability.As a result,with such collectors,the high-voltage Li//NCM811 batteries show a 6-fold increase in cycle stability,and the lithium-sulfur batteries with high sulfur loading show a 3-fold increase in cycle stability.展开更多
Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-...Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-C_(3)N_(4) suffers from limited visible-light absorption and low charge-carrier mobility.In this study,a phosphorus-doped tubular carbon nitride(5P-TCN)was synthesized via a precursor self-assembly method using phosphoric acid and melamine as raw materials,eliminating the need for organic solvents or templates.The 5P-TCN catalyst demonstrated enhanced visible-light absorption,improved charge transfer capability,and a 5.25-fold increase in specific surface area(31.092 m^(2)/g),which provided abundant active sites to efficiently drive the PMS-assisted photocatalytic reaction.The 5P-TCN/vis/PMS system exhibited exceptional degradation performance for organic pollutants across a broad pH range(3–9),achieving over 92%degradation of Rhodamine B(RhB)within 15 min.Notably,the system retained>98%RhB degradation efficiency after three consecutive operational cycles,demonstrating robust operational stability and reusability.Moreover,key parameters influencing,active radi-cals,degradation pathways,and potential mechanisms for RhB degradation were systematically investigated.This work proposes a green and cost-effective strategy for developing high-efficiency photocatalysts,while demon-strating the exceptional capability of a PMS-assisted photocatalytic system for rapid degradation of RhB.展开更多
Ion migration capability and interfacial chemistry of solid polymer electrolytes(SPEs)in all-solid-state sodium metal batteries(ASSMBs)are closely related to the Na^(+)coordination environment.Herein,an electrostatic ...Ion migration capability and interfacial chemistry of solid polymer electrolytes(SPEs)in all-solid-state sodium metal batteries(ASSMBs)are closely related to the Na^(+)coordination environment.Herein,an electrostatic engineering strategy is proposed to regulate the Na^(+)coordinated structure by employing a fluorinated metal–organic framework as an electron-rich model.Theoretical and experimental results revealed that the abundant electron-rich F sites can accelerate the disassociation of Na-salt through electrostatic attraction to release free Na^(+),while forcing anions into a Na^(+)coordination structure though electrostatic repulsion to weaken the Na^(+)coordination with polymer,thus promoting rapid Na^(+)transport.The optimized anion-rich weak solvation structure fosters a stable inorganic-dominated solid–electrolyte interphase,significantly enhancing the interfacial stability toward Na anode.Consequently,the Na/Na symmetric cell delivered stable Na plating/stripping over 2500 h at 0.1 mA cm^(−2).Impressively,the assembled ASSMBs demonstrated stable performance of over 2000 cycles even under high rate of 2 C with capacity retention nearly 100%,surpassing most reported ASSMBs using various solid-state electrolytes.This work provides a new avenue for regulating the Na^(+)coordination structure of SPEs by exploration of electrostatic effect engineering to achieve high-performance all-solid-state alkali metal batteries.展开更多
The cooperative electrostatic attraction and π-π aromatic stacking interactions between tetrahedral tetrapyridinium TP and three tetraanionic tetraphenylethylene derivatives TPE-1～3 led to the formation of a new ki...The cooperative electrostatic attraction and π-π aromatic stacking interactions between tetrahedral tetrapyridinium TP and three tetraanionic tetraphenylethylene derivatives TPE-1～3 led to the formation of a new kind of supramolecular polymer networks in water, which have been confirmed by^1 H NMR,fluorescence, isothermal titration calorimetric(ITC) and dynamic light scattering(DLS) experiments. ITC studies show that the contributions of enthalpy and entropy were comparable, reflecting the importance of hydrophobicity in driving the intermolecular aromatic stacking. DLS experiments indicate that the linear supramolecular polymers formed by these tetratopic monomers further aggregated into networks of 10~2-nm size.展开更多
Nanoparticles with competitive interactions in solution can aggregate into complex structures. In this work, the synergistic self-assembles of binary particles with electrostatic and van der Waals interactions are stu...Nanoparticles with competitive interactions in solution can aggregate into complex structures. In this work, the synergistic self-assembles of binary particles with electrostatic and van der Waals interactions are studied with the particle Langevin dynamics simulation using a simple coarse-grained particle model. Various aggregations such as spherical, stacking-disk and tube structures are observed by varying the particles size and the interaction strength. The aggregation structures are explained with the packing theories of amphiphilic molecules in solution and dibolck copolymers in bulk. When the opposite ions are introduced into solution, the distribution of structures in the phase diagram appears an obvious offset. The simulation result is helpful to deeply understand the formation mechanism of complex nanostructures of multicomponent particles in solution.展开更多
Solvation structures fundamentally control the ion-transport dynamics and mechanical properties of polymer electrolytes.However,there is a lack of strategies to rationally regulate the solvation structures and fundame...Solvation structures fundamentally control the ion-transport dynamics and mechanical properties of polymer electrolytes.However,there is a lack of strategies to rationally regulate the solvation structures and fundamental understanding on how they control the electrochemical performances.Herein,by harnessing the electrostatic adsorption of one-dimensional nanofiller(i.e.,surface-charged halloysite nanotubes,d-HNTs),we successfully fabricate a high-performance polymer nanocomposite electrolyte enabled by strong surface adsorption,referred as adsorption-state polymer electrolyte(ASPE).This ASPE shows fast ion transport(0.71±0.05 mS cm^(-1)at room temperature),high mechanical strength and toughness(10.3±0.05 MPa;15.73 MJ m^(-3)),improved lithium-ion transference number,and long cycle life with lithium metal anode,in comparison with the sample without the d-HNT adsorption effect.To fundamentally understand these high performances,an anion-rich asymmetric solvent structure model is further proposed and evidenced by both experiments and simulation studies.Results show that the electrostatic adsorption among the d-HNT,ionic liquid electrolyte,and polymer chain generates a nano filler-supported fast ion-conduction pathway with asymmetric Li+-coordination microenvironment.Meanwhile,the anion-rich asymmetric solvent structure model of ASPE also generates a fast de-solvation and anion-derived stable solid-electrolyte interphase for lithium metal anode.The high performance and understanding of the mechanism for ASPE provide a promising path to develop advanced polymer electrolytes.展开更多
Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practica...Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practical performance is limited by inhomogeneous agglomeration,increased binder requirements,and high tortuosity within the electrode.To overcome these problems and high tortuosity within the electrode,this study introduces a pomegranate-like carbon microcluster composed of primary HCSs(P-CMs)as a novel Li metal host.This unique nanostructure can be easily prepared using the spray-drying technique,enabling its mass production.Comprehensive analyses with various tools demonstrate that compared with HCS hosts,the P-CM host requires a smaller amount of binder to fabricate a sufficiently robust and even surface electrode.Furthermore,owing to reduced tortuosity,the well-designed P-CM electrode can provide continuous and shortened pathways for electron/ion transport,accelerating the Li-ion transfer kinetics and prohibiting preferential Li plating at the upper region of the electrode.Due to these characteristics,Li metal can be effectively encapsulated in the large inner voids of the primary HCSs constituting the P-CM,thereby enhancing the electrochemical performance of P-CM hosts in Li metal batteries.Specifically,the Coulombic efficiency of the P-CM host can be maintained at 97%over 100 cycles,with a high Li deposition areal capacity of 3 mAh·cm^(-2)and long cycle life(1000 h,1 mA·cm^(-2),and 1.0 mAh·cm^(-2)).Furthermore,a full cell incorporating a LiFePO4 cathode exhibits excellent cycle life.展开更多
Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,whic...Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,which can be used to construct self-assembled nanoparticles in aqueous solution driven by hydrophobic interaction.Dynamic light scattering experiments show that M1 and M2 can be driven hydrophobically to aggregate into extremely stable nanoparticles in water at the micromolar concentrations.Fluorescence titration and zeta potential experiments support that the nanoparticles formed by M1 and M2 are able to efficiently encapsulate short DNA(sDNA).Fluorescence imaging and flow cytometry studies reveal that their nano sizes enable intracellular delivery of the encapsulated sDNA into both normal and cancer cells,with delivery percentage reaching up to 94%,while in vitro experiments indicate that the two compounds have excellent biocompatibility and low cytotoxicity.展开更多
To study the influence of silicon(Si)on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20),NC/CL-20 composite explosives and Si/NC/CL-20 composite explosives were prepared by the electrostatic spraying ...To study the influence of silicon(Si)on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20),NC/CL-20 composite explosives and Si/NC/CL-20 composite explosives were prepared by the electrostatic spraying method.The morphology,structure and thermal decomposition properties of the samples were analyzed using scanning electron microscopy(SEM),X-ray energy spectroscopy(EDS),infrared spectroscopy(FT-IR),and simultaneous thermal analyzer(TG-DSC).Additionally,the combustion process of the samples was tested using a high-speed camera.The results show that the addition of nano-Si contributes to the formation of composite explosives with regular morphology and smaller particle size.The Si/NC/CL-20 composite explosive has better and more uniform sphericity,with an average particle size of 73.4 nm,compared to the NC/CL-20 composite explosive.The Si/NC/CL-20 composite explosive which produced by the electrostatic spraying method,achieves physically uniform distribution of the components including NC,CL-20,Si.The addition of Si promotes the thermal decomposition of CL-20.In comparison to the NC/CL-20 composite explosive,the activation energy of the Si/NC/CL-20 composite explosive decreases by 16.78 kJ/mol,and the self-accelerated decomposition temperature and the critical temperature of thermal explosion decreases by 3.12 K and 2.61 K,respectively.Furthermore,Si/NC/CL-20 composite explosive has shorter ignition delay time and faster combustion rate compared to the NC/CL-20 composite explosive,which shows that Si can improve the combustion performance of CL-20.展开更多
To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency...To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency,and energy are investigated for powders of different polarities.Although the powders have low charge-to-mass ratios(+0.087μC/kg for the positively charged powders and−0.26μC/kg for the negatively charged ones),electrostatic discharges occur approximately every 10 s,with the maximum discharge energy being 800 mJ.Powder polarity considerably influences discharge energy.The positive powders exhibit higher discharge energy than the negative ones,although discharge frequency remains similar for both.Effects of powder charge,humidity,and mass flow on discharge frequency and discharge energy are quantitatively analyzed,providing important insights for the improvement of safety in industrial powder handling.展开更多
Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous met...Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous metal detection,however,encounters unstable and weak signals due to nonuniform distribution of analytes.Herein,we developed an interface self-assembly(ISA)method to create a uniformly distributed gold nanolayer at a liquid-liquid interface for positive heavy metal ions capture and NELIBS analysis.The electrostatically selfassembled Au nanoparticles(NPs)-analytes membrane was prepared at the oil-water interface by injecting ethanol into the mixture of cyclohexane and Au NPs-analytes water solution.Then,the interface self-assembled Au NPs-analytes membrane was transformed onto a laser-processed superhydrophilic Si slide for detection.Three heavy metals(cadmium(Cd),barium(Ba),and chromium(Cr))were analyzed to evaluate the stability and sensitivity of the ISA method for NELIBS.The results(Cd:RSD=3.6%,LoD=0.654 mg/L;Ba:RSD=3.4%,LoD=0.236 mg/L;Cr:RSD=7.7%,LoD=1.367 mg/L)demonstrated signal enhancement and high-stable and ultrasensitive detection.The actual sample detection(Cd:RE=7.71%,Ba:RE=6.78%)illustrated great reliability.The ISA method,creating a uniform distribution of NP-analytes at the interface,has promising prospects in NELIBS.展开更多
基金supported by the National Natural Science Foundation of China(No.51972198)Shandong Provincial Science and Technology Key Project(No.2018GGX104002)+7 种基金Taishan Scholars Program of Shandong Province(No.tsqn201812002)Independent Innovation Foundation of Shandong Universitythe State Key Program of National Natural Science of China(Nos.61633015,51532005)the Young Scholars Program of Shandong University(No.2016WLJH03),the Project of the Taishan Scholar(No.ts201511004)Shandong Provincial Natural Science Foundation(No.ZR2017MB001)Discipline Construction of High-Level Talents of Shandong University(No.31370089963078)1000 Talent Plan program(No.31370086963030)the National Natural Science Foundation of China(No.21371108)。
文摘Available onlineSilicon monoxide(SiO)is a promising anode material fo r lithium-ion batteries(LIBs)due to its high theoretical specific capacity(~2400 mAh/g),low working potential(<0.5 V vs.Li^+/Li),low cost,easy synthesis,nontoxicity,abundant natural source and smaller volume expansion than Si.However,low intrinsic electrical conductivity,low initial Coulombic efficiency(ICE)and inevitable volume expansion(~200%)impede its practical application.Here we fabricate SiO/wrinkled MXene composite(SiO-WM)by an electrostatic self-assembly method.Importantly,this method is simple,scalable and taking into account all the issues of SiO.As a result,the SiO-WM exhibits imp roved rate capability,cycling performance and ICE than bare SiO.
基金financially supported by the Fundamental Research Funds for the Central Universities (No. 2019XKQYMS16)
文摘Constructing electrode materials with large capacity and good conductivity is an effective approach to improve the capacitor performance of asymmetric supercapacitors(ASCs).In this paper,ZnCo_(2)S_(4)core-shell nanospheres are constructed by two-step hydrothermal method.In order to improve the chemical activity of ZnCo_(2)S_(4),ZnCo_(2)S_(4)is activated using cetyltrimethylammonium bromide(CTAB).Then,MXene nanosheets are fixed on the surface of ZnCo_(2)S_(4)by electrostatic selfassembly method to improve the specific surface area of ZnCo_(2)S_(4)and MXene-wrapped ZnCo_(2)S_(4)composite is prepared in this work.Owing to the synergy effect between MXene nanosheets and ZnCo_(2)S_(4)core-shell nanospheres,the as-prepared composite displays fast ion transfer rate and charge/discharge process.The capacity of the MXenewrapped ZnCo_(2)S_(4)composite can reach 1072 F·g^(-1),which is far larger than that of ZnCo_(2)S_(4)(407 F·g^(-1))at 1 A·g^(-1).An ASC device is assembled,which delivers 1.7 V potential window and superior cyclic stability(95.41%capacitance retention).Furthermore,energy density of this device is up to 30.46 Wh·kg^(-1)at a power density of850 W·kg^(-1).The above results demonstrate that MXenewrapped ZnCo_(2)S_(4)composite has great application prospects in electrochemical energy storage field.
基金Funded by the Natural Science Foundation of Hebei Province, China (No. E2008000537)the Foundation for Development of Science and Technology of Hebei Province, China (No. 07215156)the Open Research Foundation of Key Laboratory of Advanced Civil Engineering Materials (Tongji University),Ministry of Education, China (No. 2010412)
文摘Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spectroscopy （FT-IR） and scanning electron microscopy （SEM）. Methyl orange was used to estimate the photocatalytic activity of the materials. The effects of the calcination temperature and silane dosage on the photocatalytic activity of the samples were investigated. The experimental results show that the bentonite facilitates the formation of anatase and restrains the transformation of anatase to rutile. Part of nano-size TiO2 particles insert into the galleries of bentonite. The photocatalysts exhibit a synergistic effect of adsorption and photocatalysis on methyl orange. Photocatalysts prepared by ESAM method exhibit higher photocatalytic activity and better recycle ability than those of the traditional method.
文摘Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (ESA) method. The whole self-assemble process, the function of surfactant and the effect of TiO_2 slurry′s concentration to the self-assemble were discussed. The isoelectric point of TiO_2 slurry measured by experiment is 6.8. The results show that whatever the concentration of the TiO_2 dispersion, a flat and compact adsorbed monolayer on the optic fiber can be built in a stable dispersion at lower pH. There is a adsorbed equilibrium on the substrate (fiber)/solution interface when enough time of incubation is given. A rough and loosen adsorbed layer is formed on the fiber surface by immersed the substrate in a high pH dispersion (pH>10) because the presence of hydroxyl on particle surface. Film thickness can be controlled by controlling the number of layers in the film.
基金This research was financially supported by China Scholar-ship Council and the Natural Science Foundation of Hubei Province (Project 2000J002)
文摘Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin films on si/icon and quartz substrates. The paniculate thin films were characterized by UV-vis spea-troscopy, surface, enhanced Raman scattering, atomic force microscopy and resistivity measurements. Due to the interparticle coupling between individual gold particles, an obvious collective particle plasmon resonance was ob-served on UV-vis spectra , and the particulate thin films exhibited a strong SERS effect. For multilayer thin films with a high particle coverage on substrates , resistivity of the order of 10-4 Ω·cm was yielded.
基金supported by the National Nature Science Foundation of China(No.51562006)Guangxi Distinguished Experts Special Fund(No.2019B06)Innovation Project of Guangxi Graduate Education(No.SC2200000985).
文摘Aqueous zinc ion batteries have become highly favored energy storage devices owing to low cost and environmental friendliness.Vanadium oxide,as one of the potential cathodes for AZIBs,is plagued by several unfavorable elements including unsatisfactory conductivity and vanadium dissolution in the electrolyte.Herein,an electrostatic self-assembly strategy is proposed to introduce conductive dielectric Ti_(3)C_(2)T_(x)MXene nanoplates into V_(2)O_(5)·4VO_(2)nanoribbons,where V_(2)O_(5)·4VO_(2)/MXene composites(denoted as VM2)are simply obtained by magnetic stirring combined with ultrasonic method at room temperature.The successful introduction of MXene with high electrical conductivity not only endows faster V_(2)O_(5)·4VO_(2)electron/ion transfer,but also acts as a"baffle"to inhibit vanadium dissolution.Benefiting from the above advantages,paired with a zinc metal anode,VM2 cathode exhibits impressive performance metrics of 328.7 mAh·g^(−1)at 0.1 A·g^(−1),95.8%capacity retention after 1000 cycles,and 142.9 mAh·g^(−1)at a current density of 20 A·g^(−1).This work provides a viable reference for the development of high-performance AZIBs.
基金The authors gratefully acknowledge the support for this work from the National Key research and Development Program(Grant No.2018YFA0703100)the National Natural Science Foundation of China(Grant Nos.82072082,31900959)+2 种基金the Youth Innovation Promotion Association of CAS(Grant No.2019350)the Guangdong Natural Science Foundation(Grant No.2019A1515011277)the Shenzhen Fundamental Research Foundation(Grant No.JCYJ20180507182237428).
文摘Low patency ratio of small-diameter vascular grafts remains a major challenge due to the occurrence of thrombosis formation and intimal hyperplasia after transplantation.Although developing the functional coating with release of bioactive molecules on the surface of small-diameter vascular grafts are reported as an effective strategy to improve their patency ratios,it is still difficult for current functional coatings cooperating with spatiotemporal control of bioactive molecules release to mimic the sequential requirements for antithrombogenicity and endothelialization.Herein,on basis of 3D-printed polyelectrolyte-based vascular grafts,a biologically inspired release system with sequential release in spatiotemporal coordination of dual molecules through an electrostatic self-assembly was first described.A series of tubes with tunable diameters were initially fabricated by a coaxial extrusion printing method with customized nozzles,in which a polyelectrolyte ink containing of ε-polylysine and sodium alginate was used.Further,dual bioactive molecules,heparin with negative charges and Tyr-Ile-Gly-Ser-Arg(YIGSR)peptide with positive charges were layer-by-layer assembled onto the surface of these 3D-printed tubes.Due to the electrostatic interaction,the sequential release of heparin and YIGSR was demonstrated and could construct a dynamic microenvironment that was thus conducive to the antithrombogenicity and endothelialization.This study opens a new avenue to fabricate a small-diameter vascular graft with a biologically inspired release system based on electrostatic interaction,revealing a huge potential for development of small-diameter artificial vascular grafts with good patency.
基金National Key Research and Development Program of China(2017YFB0903804)Science and Technology Program of the State Grid Corporation of China(No.5455DW170026).
文摘High-performance epoxy(EP)composites with excellent thermal conductivity and dielectric properties have attracted increasing attention for effective thermal management.In this work,three-dimensional(3D)structural functional fillers were prepared by an electrostatic self-assembly approach.The negatively charged carbon nanotubes(nCNTs)prepared by carboxylation on the surface of CNTs were attached to the positively charged boron nitride(pBN)to form the 3D pBN@nCNTs functional fillers.The morphological characterizations of the formed 3D pBN@nCNTs fillers and epoxy composites were established,illustrating that nCNTs were linearly overlapped between the BN sheets,thus forming a 3D heat conduction network in the epoxy matrix.The synergistic effect of pBN with nCNTs on the enhancement of thermal conductivity and dielectric properties of composites was systematically studied.The experimental results demonstrated that the thermal conductivity of pBN@nCNTs/EP composites could reach 1.986 W m1K1 with the loading of 50 wt%fillers at 10:1 mass ratio of pBN:nCNTs,which is 464%and 124%higher than that of pure EP and BN/EP,respectively.Simultaneously,the dielectric permittivity was successfully increased to 15.14.Moreover,the thermal stability of the composites was synchronously enhanced.This study provides a facile path to fabricate thermosetting polymer composites with high thermal conductivity and dielectric properties.
基金supported by the National Natural Science Foundation of China(No.51706105)。
文摘Al/NH_(4)CoF_(3)-Φ(Φ=0.5,1.0,1.5,2.0,and 3.0)binary composites and Al-NH_(4)CoF_(3)@P(VDF-HFP)ternary composites are fabricated via ultrasonication-assisted blending and electrostatic spraying.The effect of equivalence ratio(Φ)on the reaction properties is systematically investigated in the binary Al/NH_(4)CoF_(3)system.For ternary systems,electrostatic spraying allows both components to be efficiently encapsulated by P(VDF-HFP)and to achieve structural stabilization and enhanced reactivity through synergistic interfacial interactions.Morphological analysis using SEM/TEM revealed that P(VDF-HFP)formed a protective layer on Al and NH_(4)CoF_(3)particles,improving dispersion,hydrophobicity(water contact angle increased by 80.5%compared to physically mixed composites),and corrosion resistance.Thermal decomposition of NH_(4)CoF_(3)occurred at 265℃,releasing NH_(3)and HF,which triggered exothermic reactions with Al.The ternary composites exhibited a narrowed main reaction temperature range and concentrated heat release,attributed to improved interfacial contact and polymer decomposition.Combustion tests demonstrated that Al-NH_(4)CoF_(3)@P(VDF-HFP)achieved self-sustaining combustion.In addition,a simple validation was done by replacing the Al component in the aluminium-containing propellant,demonstrating its potential application in the propellant field.This work establishes a novel strategy for designing stable,high-energy composites with potential applications in advanced propulsion systems.
基金the National Natural Science Foundation of China(No.U22A20437)Joint Fund of Science and Technology R&D Plan of Henan Province(No.222301420005)Program for Innovative Research Team(in Science and Technology)in University of Henan Province(No.24IRTSTHN001)for financial support.
文摘Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered assembly of graphene oxide(GO)nanosheets in solution films can be realized to obtain the high-quality and large-area reduced GO(rGO)films.The key to the success of this process primarily lies in the control of GO solution shear force direction with array capillaries,achieving oriented arrangement of GO nanosheets in the solution film.Secondly,the control of GO nanosheet concentration and solution viscosity during solvent evaporation of solution film is key to achieve the ordered and disordered assembly of GO,featuring the smooth and wrinkled structure rGO films,respectively.Subsequently,the resultant smooth rGO film with ordered assembly exhibits excellent thermal conductivity and electronic conductivity(over 1800 S·cm-1).Meanwhile,the wrinkled rGO film with disordered assembly can be used as a coating layer on Al current collectors,demonstrating anticorrosion properties and enhanced material adhesive stability.As a result,with such collectors,the high-voltage Li//NCM811 batteries show a 6-fold increase in cycle stability,and the lithium-sulfur batteries with high sulfur loading show a 3-fold increase in cycle stability.
文摘Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-C_(3)N_(4) suffers from limited visible-light absorption and low charge-carrier mobility.In this study,a phosphorus-doped tubular carbon nitride(5P-TCN)was synthesized via a precursor self-assembly method using phosphoric acid and melamine as raw materials,eliminating the need for organic solvents or templates.The 5P-TCN catalyst demonstrated enhanced visible-light absorption,improved charge transfer capability,and a 5.25-fold increase in specific surface area(31.092 m^(2)/g),which provided abundant active sites to efficiently drive the PMS-assisted photocatalytic reaction.The 5P-TCN/vis/PMS system exhibited exceptional degradation performance for organic pollutants across a broad pH range(3–9),achieving over 92%degradation of Rhodamine B(RhB)within 15 min.Notably,the system retained>98%RhB degradation efficiency after three consecutive operational cycles,demonstrating robust operational stability and reusability.Moreover,key parameters influencing,active radi-cals,degradation pathways,and potential mechanisms for RhB degradation were systematically investigated.This work proposes a green and cost-effective strategy for developing high-efficiency photocatalysts,while demon-strating the exceptional capability of a PMS-assisted photocatalytic system for rapid degradation of RhB.
基金supported by the National Natural Science Foundation of China(No.52473213 and No.52203261)。
文摘Ion migration capability and interfacial chemistry of solid polymer electrolytes(SPEs)in all-solid-state sodium metal batteries(ASSMBs)are closely related to the Na^(+)coordination environment.Herein,an electrostatic engineering strategy is proposed to regulate the Na^(+)coordinated structure by employing a fluorinated metal–organic framework as an electron-rich model.Theoretical and experimental results revealed that the abundant electron-rich F sites can accelerate the disassociation of Na-salt through electrostatic attraction to release free Na^(+),while forcing anions into a Na^(+)coordination structure though electrostatic repulsion to weaken the Na^(+)coordination with polymer,thus promoting rapid Na^(+)transport.The optimized anion-rich weak solvation structure fosters a stable inorganic-dominated solid–electrolyte interphase,significantly enhancing the interfacial stability toward Na anode.Consequently,the Na/Na symmetric cell delivered stable Na plating/stripping over 2500 h at 0.1 mA cm^(−2).Impressively,the assembled ASSMBs demonstrated stable performance of over 2000 cycles even under high rate of 2 C with capacity retention nearly 100%,surpassing most reported ASSMBs using various solid-state electrolytes.This work provides a new avenue for regulating the Na^(+)coordination structure of SPEs by exploration of electrostatic effect engineering to achieve high-performance all-solid-state alkali metal batteries.
基金National Natural Science Foundation of China (Nos. 21432004 and 21472023) for financial support
文摘The cooperative electrostatic attraction and π-π aromatic stacking interactions between tetrahedral tetrapyridinium TP and three tetraanionic tetraphenylethylene derivatives TPE-1～3 led to the formation of a new kind of supramolecular polymer networks in water, which have been confirmed by^1 H NMR,fluorescence, isothermal titration calorimetric(ITC) and dynamic light scattering(DLS) experiments. ITC studies show that the contributions of enthalpy and entropy were comparable, reflecting the importance of hydrophobicity in driving the intermolecular aromatic stacking. DLS experiments indicate that the linear supramolecular polymers formed by these tetratopic monomers further aggregated into networks of 10~2-nm size.
基金V. ACKNOWLEDGMENTS The computer simulation is performed on the High Performance Computing Center of Tianjin University,China. This work was supported by the National Natural Science Foundation of China （No.21274107 and No.91127046）. We thank Prof. Bin Zhang, Rui Xu, Bo Du, and Dr. Zi-lu Wang in Tianjin University for helpful discussions.
文摘Nanoparticles with competitive interactions in solution can aggregate into complex structures. In this work, the synergistic self-assembles of binary particles with electrostatic and van der Waals interactions are studied with the particle Langevin dynamics simulation using a simple coarse-grained particle model. Various aggregations such as spherical, stacking-disk and tube structures are observed by varying the particles size and the interaction strength. The aggregation structures are explained with the packing theories of amphiphilic molecules in solution and dibolck copolymers in bulk. When the opposite ions are introduced into solution, the distribution of structures in the phase diagram appears an obvious offset. The simulation result is helpful to deeply understand the formation mechanism of complex nanostructures of multicomponent particles in solution.
基金financial support from the National Natural Science Foundation of China(52203123)the Sichuan Science and Technology Program(2023NSFSC0991)+2 种基金the State Key Laboratory of Polymer Materials Engineering(sklpme 2023-1-05 and sklpme 2024-2-04)the Fundamental Research Funds for the Central Universitiespartially sponsored by the Double First-Class Construction Funds of Sichuan University。
文摘Solvation structures fundamentally control the ion-transport dynamics and mechanical properties of polymer electrolytes.However,there is a lack of strategies to rationally regulate the solvation structures and fundamental understanding on how they control the electrochemical performances.Herein,by harnessing the electrostatic adsorption of one-dimensional nanofiller(i.e.,surface-charged halloysite nanotubes,d-HNTs),we successfully fabricate a high-performance polymer nanocomposite electrolyte enabled by strong surface adsorption,referred as adsorption-state polymer electrolyte(ASPE).This ASPE shows fast ion transport(0.71±0.05 mS cm^(-1)at room temperature),high mechanical strength and toughness(10.3±0.05 MPa;15.73 MJ m^(-3)),improved lithium-ion transference number,and long cycle life with lithium metal anode,in comparison with the sample without the d-HNT adsorption effect.To fundamentally understand these high performances,an anion-rich asymmetric solvent structure model is further proposed and evidenced by both experiments and simulation studies.Results show that the electrostatic adsorption among the d-HNT,ionic liquid electrolyte,and polymer chain generates a nano filler-supported fast ion-conduction pathway with asymmetric Li+-coordination microenvironment.Meanwhile,the anion-rich asymmetric solvent structure model of ASPE also generates a fast de-solvation and anion-derived stable solid-electrolyte interphase for lithium metal anode.The high performance and understanding of the mechanism for ASPE provide a promising path to develop advanced polymer electrolytes.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.2020R1C1C1003375)。
文摘Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practical performance is limited by inhomogeneous agglomeration,increased binder requirements,and high tortuosity within the electrode.To overcome these problems and high tortuosity within the electrode,this study introduces a pomegranate-like carbon microcluster composed of primary HCSs(P-CMs)as a novel Li metal host.This unique nanostructure can be easily prepared using the spray-drying technique,enabling its mass production.Comprehensive analyses with various tools demonstrate that compared with HCS hosts,the P-CM host requires a smaller amount of binder to fabricate a sufficiently robust and even surface electrode.Furthermore,owing to reduced tortuosity,the well-designed P-CM electrode can provide continuous and shortened pathways for electron/ion transport,accelerating the Li-ion transfer kinetics and prohibiting preferential Li plating at the upper region of the electrode.Due to these characteristics,Li metal can be effectively encapsulated in the large inner voids of the primary HCSs constituting the P-CM,thereby enhancing the electrochemical performance of P-CM hosts in Li metal batteries.Specifically,the Coulombic efficiency of the P-CM host can be maintained at 97%over 100 cycles,with a high Li deposition areal capacity of 3 mAh·cm^(-2)and long cycle life(1000 h,1 mA·cm^(-2),and 1.0 mAh·cm^(-2)).Furthermore,a full cell incorporating a LiFePO4 cathode exhibits excellent cycle life.
文摘Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,which can be used to construct self-assembled nanoparticles in aqueous solution driven by hydrophobic interaction.Dynamic light scattering experiments show that M1 and M2 can be driven hydrophobically to aggregate into extremely stable nanoparticles in water at the micromolar concentrations.Fluorescence titration and zeta potential experiments support that the nanoparticles formed by M1 and M2 are able to efficiently encapsulate short DNA(sDNA).Fluorescence imaging and flow cytometry studies reveal that their nano sizes enable intracellular delivery of the encapsulated sDNA into both normal and cancer cells,with delivery percentage reaching up to 94%,while in vitro experiments indicate that the two compounds have excellent biocompatibility and low cytotoxicity.
基金National Natural Science Foundation of China(No.22275150)。
文摘To study the influence of silicon(Si)on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20),NC/CL-20 composite explosives and Si/NC/CL-20 composite explosives were prepared by the electrostatic spraying method.The morphology,structure and thermal decomposition properties of the samples were analyzed using scanning electron microscopy(SEM),X-ray energy spectroscopy(EDS),infrared spectroscopy(FT-IR),and simultaneous thermal analyzer(TG-DSC).Additionally,the combustion process of the samples was tested using a high-speed camera.The results show that the addition of nano-Si contributes to the formation of composite explosives with regular morphology and smaller particle size.The Si/NC/CL-20 composite explosive has better and more uniform sphericity,with an average particle size of 73.4 nm,compared to the NC/CL-20 composite explosive.The Si/NC/CL-20 composite explosive which produced by the electrostatic spraying method,achieves physically uniform distribution of the components including NC,CL-20,Si.The addition of Si promotes the thermal decomposition of CL-20.In comparison to the NC/CL-20 composite explosive,the activation energy of the Si/NC/CL-20 composite explosive decreases by 16.78 kJ/mol,and the self-accelerated decomposition temperature and the critical temperature of thermal explosion decreases by 3.12 K and 2.61 K,respectively.Furthermore,Si/NC/CL-20 composite explosive has shorter ignition delay time and faster combustion rate compared to the NC/CL-20 composite explosive,which shows that Si can improve the combustion performance of CL-20.
基金The National Natural Science Foundation of China(No.51976039)。
文摘To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency,and energy are investigated for powders of different polarities.Although the powders have low charge-to-mass ratios(+0.087μC/kg for the positively charged powders and−0.26μC/kg for the negatively charged ones),electrostatic discharges occur approximately every 10 s,with the maximum discharge energy being 800 mJ.Powder polarity considerably influences discharge energy.The positive powders exhibit higher discharge energy than the negative ones,although discharge frequency remains similar for both.Effects of powder charge,humidity,and mass flow on discharge frequency and discharge energy are quantitatively analyzed,providing important insights for the improvement of safety in industrial powder handling.
基金supported by the National Natural Science Foundation of China(No.62075069 and 52303092)the Water Conservancy Technology project of Hunan Province,China(XSKJ2021000-32)+1 种基金the City University of Hong Kong(#7005507)the Open Project of Yunnan Precious Metals Laboratory Co.,Ltd(grant number YPML-2023050278).
文摘Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous metal detection,however,encounters unstable and weak signals due to nonuniform distribution of analytes.Herein,we developed an interface self-assembly(ISA)method to create a uniformly distributed gold nanolayer at a liquid-liquid interface for positive heavy metal ions capture and NELIBS analysis.The electrostatically selfassembled Au nanoparticles(NPs)-analytes membrane was prepared at the oil-water interface by injecting ethanol into the mixture of cyclohexane and Au NPs-analytes water solution.Then,the interface self-assembled Au NPs-analytes membrane was transformed onto a laser-processed superhydrophilic Si slide for detection.Three heavy metals(cadmium(Cd),barium(Ba),and chromium(Cr))were analyzed to evaluate the stability and sensitivity of the ISA method for NELIBS.The results(Cd:RSD=3.6%,LoD=0.654 mg/L;Ba:RSD=3.4%,LoD=0.236 mg/L;Cr:RSD=7.7%,LoD=1.367 mg/L)demonstrated signal enhancement and high-stable and ultrasensitive detection.The actual sample detection(Cd:RE=7.71%,Ba:RE=6.78%)illustrated great reliability.The ISA method,creating a uniform distribution of NP-analytes at the interface,has promising prospects in NELIBS.
