In-situ thermal Raman mapping and stress analysis of CNT/CF/epoxy interfaces

A study of the interfacial behavior and internal thermal stress distribution in fiber-reinforced composites is essential to assess their performance and reliability.CNT/carbon fiber(CF)hybrid fibers were constructed using electrophoretic deposition.The interfacial properties of CF/epoxy and CNT/CF/epoxy composites were statistically investigated and compared using in-situ thermal Raman mapping by dispersing CNTs as a Raman sensing medium(CNT_(R))in a resin.The associated local thermal stress changes can be simulated by capturing the G'band position distribution of CNT_(R) in the epoxy at different temperatures.It was found that the G'band shifted to lower positions with increasing temperature,reaching a maximum difference of 2.43 cm^(−1) at 100℃.The interfacial bonding between CNT/CF and the matrix and the stress distribution and changes during heat treatment(20-100℃)were investig-ated in detail.This work is important for studying thermal stress in fiber-reinforced composites by in-situ thermal Raman mapping technology.

Engineering homotype heterojunctions in hard carbon to induce stable solid electrolyte interfaces for sodium-ion batteries

Developing effective strategies to improve the initial Coulombic efficiency(ICE)and cycling stability of hard carbon(HC)anodes for sodium-ion batteries is the key to promoting the commercial application of HC.In this paper,homotype heterojunctions are designed on HC to induce the generation of stable solid electrolyte interfaces,which can effectively increase the ICE of HC from 64.7%to 81.1%.The results show that using a simple surface engineering strategy to construct a homotypic amorphous Al_(2)O_(3) layer on the HC could shield the active sites,and further inhibit electrolyte decomposition and side effects occurrence.Particularly,due to the suppression of continuous decomposition of NaPF 6 in ester-based electrolytes,the accumulation of NaF could be reduced,leading to the formation of thinner and denser solid electrolyte interface films and a decrease in the interface resistance.The HC anode can not only improve the ICE but elevate its sodium storage performance based on this homotype heterojunction composed of HC and Al_(2)O_(3).The optimized HC anode exhibits an outstanding reversible capacity of 321.5mAhg^(−1) at 50mAg^(−1).The cycling stability is also improved effectively,and the capacity retention rate is 86.9%after 2000 cycles at 1Ag^(−1) while that of the untreated HC is only 52.6%.More importantly,the improved sodium storage behaviors are explained by electrochemical kinetic analysis.

Study of the Diffusion Behavior of Seawater Absorption in Multi-Walled Carbon Nanotubes/Halloysite Nanotubes Hybrid Nanofillers Modified Epoxy-Based Glass/Carbon Fiber Composites

In the maritime industry, cost-effective and lightweight Fiber Reinforced Polymer (FRP) composites offer excellent mechanical properties, design flexibility, and corrosion resistance. However, their reliability in harsh seawater conditions is a concern. Researchers address this by exploring three approaches: coating fiber surfaces, hybridizing fibers and matrices with or without nanofillers, and interply rearrangement. This study focuses on evaluating the synergistic effects of interply rearrangement of glass/carbon fibers and hybrid nanofillers, specifically Multi-walled carbon nanotubes (MWCNT) and Halloysite nanotubes (HNT). The aim is to enhance impact properties by minimizing moisture absorption. Hybrid nanocomposites with equal-weight proportions of two nanofillers: 0 wt.%, 1 wt.%, and 2 wt.% were exposed to seawater for 90 days. Experimental data was subjected to modelling through the application of Predictive Fick’s Law. The study found that the hybrid composite containing 2 wt.% hybrid nanofillers exhibited a 22.10% increase in impact performance compared to non-modified counterparts. After 90 days of seawater aging, the material exhibited enhanced resistance to moisture absorption (15.74%) and minimal reduction in impact strength (8.52%) compared to its dry strength, with lower diffusion coefficients.

Interfacial design of silicon/carbon anodes for rechargeable batteries:A review

Silicon(Si)has been studied as a promising alloying type anode for lithium-ion batteries due to its high specific capacity,low operating potential and abundant resources.Nevertheless,huge volume expansion during alloying/dealloying processes and low electronic conductivity of Si anodes restrict their electrochemical performance.Thus,carbon(C)materials with special physical and chemical properties are applied in Si anodes to effectively solve these problems.This review focuses on current status in the exploration of Si/C anodes,including the lithiation mechanism and solid electrolyte interface formation,various carbon sources in Si/C anodes,such as traditional carbon sources(graphite,pitch,biomass),and novel carbon sources(MXene,graphene,MOFs-derived carbon,graphdiyne,etc.),as well as interfacial bonding modes of Si and C in the Si/C anodes.Finally,we summarize and prospect the selection of carbonaceous materials,structural design and interface control of Si/C anodes,and application of Si/C anodes in all-solid-state lithium-ion batteries and sodium-ion batteries et al.This review will help researchers in the design of novel Si/C anodes for rechargeable batteries.

Interface electron collaborative migration of Co–Co3O4/carbon dots:Boosting the hydrolytic dehydrogenation of ammonia borane

Ammonia borane(AB)is an excellent candidate for the chemical storage of hydrogen.However,its practical utilization for hydrogen production is hindered by the need for expensive noble-metal-based catalysts.Herein,we report Co-Co3O4 nanoparticles(NPs)facilely deposited on carbon dots(CDs)as a highly efficient,robust,and noble-metal-free catalyst for the hydrolysis of AB.The incorporation of the multiinterfaces between Co,Co3O4 NPs,and CDs endows this hybrid material with excellent catalytic activity(rB=6816 mLH2 min^-1 gCo^-1)exceeding that of previous non-noble-metal NP systems and even that of some noble-metal NP systems.A further mechanistic study suggests that these interfacial interactions can affect the electronic structures of interfacial atoms and provide abundant adsorption sites for AB and water molecules,resulting in a low energy barrier for the activation of reactive molecules and thus substantial improvement of the catalytic rate.

Carbon dots regulate the interface electron transfer and catalytic kinetics of Pt-based alloys catalyst for highly efficient hydrogen oxidation

The regulation of interface electron-transfer and catalytic kinetics is very important to design the efficient electrocatalyst for alkaline hydrogen oxidation reaction(HOR).Here,we show the Pt-Ni alloy nanoparticles(PtNi_(2))have an enhanced HOR activity compared with single component Pt catalyst.While,the interface electron-transfer kinetics of PtNi_(2)catalyst exhibits a very wide electron-transfer speed distribution.When combined with carbon dots(CDs),the interface charge transfer of PtNi_(2)-CDs composite is optimized,and then the PtNi_(2)-5 mg CDs exhibits about 2.67 times and 4.04 times higher mass and specific activity in 0.1 M KOH than that of 20%commercial Pt/C.In this system,CDs also contribute to trapping H^(+)and H_(2)O generated during HOR,tuning hydrogen binding energy(HBE),and regulating interface electron transfer.This work provides a deep understanding of the interface catalytic kinetics of Pt-based alloys towards highly efficient HOR catalysts design.

Mechanical Property Evaluation of Glass-carbon-durian Skin Fiber Reinforced Polylactic Acid Composites

The main objective of this work was to study and develop composite materials by experiments with mixtures of synthetic(glass fiber, carbon fiber) and natural fiber(durian skin fiber) reinforcements on a polylactic acid(PLA) matrix composite, because of its excellent mechanical properties. Durian skin fiber(DSF) is a natural waste throughout Thailand, and an alternative to recycling is to realize its potential as a new reinforcement through mixing and the injection molding processes. The flexural strength(σ_(F)) and flexural modulus(E_(F)) of the composites from specimens showed a maximum value by content of durian skin fiber at 10 wt%, for good performance relative to particle dispersion between the matrix and the fiber, and showed a minimum value by content of durian skin fiber at 20 wt%, because the reinforcement material affects the mechanical properties in the experiments.

Tuning Interface Bridging Between MoSe2 and Three‑Dimensional Carbon Framework by Incorporation of MoC Intermediate to Boost Lithium Storage Capability

Interface engineering has been widely explored to improve the electrochemical performances of composite electrodes,which governs the interface charge transfer,electron transportation,and structural stability.Herein,MoC is incorporated into MoSe2/C composite as an intermediate phase to alter the bridging between MoSe2-and nitrogen-doped three-dimensional(3D)carbon framework as MoSe2/MoC/N–C connection,which greatly improve the structural stability,electronic conductivity,and interfacial charge transfer.Moreover,the incorporation of MoC into the composites inhibits the overgrowth of MoSe2 nanosheets on the 3D carbon framework,producing much smaller MoSe2 nanodots.The obtained MoSe2 nanodots with fewer layers,rich edge sites,and heteroatom doping ensure the good kinetics to promote pseudo-capacitance contributions.Employing as anode material for lithium-ion batteries,it shows ultralong cycle life(with 90%capacity retention after 5000 cycles at 2 A g−1)and excellent rate capability.Moreover,the constructed LiFePO4//MoSe2/MoC/N–C full cell exhibits over 86%capacity retention at 2 A g−1 after 300 cycles.The results demonstrate the effectiveness of the interface engineering by incorporation of MoC as interface bridging intermediate to boost the lithium storage capability,which can be extended as a potential general strategy for the interface engineering of composite materials.

Smart Interfacing between Co-Fe Layered Double Hydroxide and Graphitic Carbon Nitride for High-efficiency Electrocatalytic Nitrogen Reduction

Bimetallic compounds such as hydrotalcite-type layered double hydroxides(LDHs)are promising electrocatalysts owing to their unique electronic structures.However,their abilities toward nitrogen adsorption and reduction are undermined since the surface-mantled,electronegative-OH groups hinder the charge transfer between transition metal atoms and nitrogen molecules.Herein,a smart interfacing strategy is proposed to construct a coupled heterointerface between LDH and 2D g-C_(3)N_(4),which is proven by density functional theory(DFT)investigations to be favorable for nitrogen adsorption and ammonia desorption compared with neat LDH surface.The interfaced LDH and g-C_(3)N_(4) is further hybridized with a self-standing TiO_(2) nanofibrous membrane(NM)to maximize the interfacial effect owing to its high porosity and large surface area.Profited from the synergistic superiorities of the three components,the LDH@C_(3)N_(4)@TiO_(2) NM delivers superior ammonia yield(2.07×10^(−9) mol s^(−1) cm^(−2))and Faradaic efficiency(25.3%),making it a high-efficiency,noble-metal-free catalyst system toward electrocatalytic nitrogen reduction.

Triple-phase interfaces of graphene-like carbon clusters on antimony trisulfide nanowires enable high-loading and long-lasting liquid Li_(2)S_(6)-based lithium-sulfur batteries

High performance of lithium-sulfur batteries have been dragged down by their shuttling behavior which is complicated multiphase transition-based 16-electron redox reactions of the S8/Li2 S.In this article,the triple-phase interfaces of graphene-like carbon clusters on antimony trisulfide(C-Sb_(2)S_(3))nanowires are tailored to design a multifunctional polysulfide host which can inhibit migration of polysulfides and accelerate conversion kinetics of redox electrochemical reactions.Benefiting from the triple-interface design of polysulfides/Sb_(2)S_(3)/carbon clusters,the C-Sb_(2)S_(3) electrode not only anchors polysulfide migration by the synergistic effect of Sb,S,and C atoms as interfacial active sites,but also the graphene-like carbon clusters shorten the diffusion paths to further favor redox electron/ion transport through the liquid(electrolyte/polysulfide)and solid(Li2 S/S8,carbon clusters,and Sb_(2)S_(3))-based triple-phases.Therefore,these Li_(2)S_(6)-based C-Sb_(2)S_(3) cells possess high sulfur loading,excellent cycling stability,impressive specific capacity,and great rate capability.This work of interfacial engineering reveals insight for powering reaction kinetics in the complicated multistep catalysis reaction with multiphase evolution-based chargetransfer/non-transfer processes.

Tuned selectivity and enhanced activity of CO_(2) methanation over Ru catalysts by modified metal-carbonate interfaces

Carbonate-modified metal-support interfaces allow Ru/MnCO_(3) catalyst to exhibit over 99% selectivity,great specific activity and long-term anti-CO poisoning stability in atmospheric CO_(2) methanation.As a contrast,Ru/MnO catalyst with metal-oxide interfaces prefers reverse water-gas shift rather than methanation route,along with a remarkably lower activity and a less than 15% CH_(4) selectivity.The carbonatemodified interfaces are found to stabilize the Ru species and activate CO_(2) and H_(2) molecules.Ru-CO^(4) species are identified as the reaction intermediates steadily formed from CO_(2) dissociation,which show moderate adsorption strength and high reactivity in further hydrogenation to CH_(4),Furthermore,carbonates of Ru/MnCO_(3) are found to be consumed by hydrogenation to form CH_(4) and replenished by exchange with CO_(2),which are in a dynamic equilibrium during the reaction.Modification with surface carbonates is proved as an efficient strategy to endow metal-support interfaces of Ru-based catalysts with unique catalytic functions for selective CO_(2) hydrogenation.

Regulatable Orthotropic 3D Hybrid Continuous Carbon Networks for Efficient Bi-Directional Thermal Conduction

Vertically oriented carbon structures constructed from low-dimen-sional carbon materials are ideal frameworks for high-performance thermal inter-face materials(TIMs).However,improving the interfacial heat-transfer efficiency of vertically oriented carbon structures is a challenging task.Herein,an orthotropic three-dimensional(3D)hybrid carbon network(VSCG)is fabricated by depositing vertically aligned carbon nanotubes(VACNTs)on the surface of a horizontally oriented graphene film(HOGF).The interfacial interaction between the VACNTs and HOGF is then optimized through an annealing strategy.After regulating the orientation structure of the VACNTs and filling the VSCG with polydimethylsi-loxane(PDMS),VSCG/PDMS composites with excellent 3D thermal conductive properties are obtained.The highest in-plane and through-plane thermal conduc-tivities of the composites are 113.61 and 24.37 W m^(-1)K^(-1),respectively.The high contact area of HOGF and good compressibility of VACNTs imbue the VSCG/PDMS composite with low thermal resistance.In addition,the interfacial heat-transfer efficiency of VSCG/PDMS composite in the TIM performance was improved by 71.3%compared to that of a state-of-the-art thermal pad.This new structural design can potentially realize high-performance TIMs that meet the need for high thermal conductivity and low contact thermal resistance in interfacial heat-transfer processes.

Carbon dioxide partial pressure and carbon fluxes of air-water interface in Taihu Lake, China

To obtain carbon dioxide (CO2) flux between water-air interface of Taihu lake, monthly water samplers at 14 sites and the local meteorological data of the lake were collected and analyzed in 1998. Carbon dioxide partial pressures (pCO2) at air-water interface in the lake were calculated using alkalinity, pH, ionic strength, active coefficient, and water temperature. The carbon fluxes at different sublakes and areas were estimated by concentration gradient between water and air in consideration of Schmidt numbers of 600 and daily mean windspeed at 10 m above water surface. The results indicated that the mean values of pCO2 in Wuli Lake, Meiliang Bay, hydrophyte area, west littoral zone, riverine mouths, and the open lake areas were 1 807.8±1 071.4 (mean±standard deviation) μatm (1atm=1.013 25×105Pa), 416.3±217.0 μatm, 576.5±758.8 μatm, 304.2±243.5 μatm, 1 933.6±1 144.7 μatm, and 448.5±202.6 μatm, respectively. Maximum and minimum pCO2 values were found in the hypertrophic (4 053.7 μatm) and the eutrophic (3.2 μatm) areas. The riverine mouth areas have the maximum fluxes (82.0±62.8 mmol/m2a). But there was no significant difference between eutrophic and mesot- rophic areas in pCO2 and the flux of CO2. The hydrophyte area, however, has the minimum (-0.58±12.9 mmol/m2a). In respect to CO2 equilibrium, input of the rivers will obviously influence inorganic carbon distribu- tion in the riverine estuary. For example, the annual mean CO2 flux in Zhihugang River estuary was 19 times of that in Meiliang Bay, although the former is only a part of the latter. The sites in the body of the lake show a clear seasonal cycle with pCO2 higher than atmospheric equilibrium in winter, and much lower than atmospheric in summer due to CO2 consumption by photosynthesis. The CO2 amount of the net annual evasion that enters the atmosphere is 28.42×104 t/a, of which those from the west littoral zone and the open lake account for 53.8% and 36.7%, respectively.

Test Method to Simulate the Influence of the Interface on the Concrete Carbonation Process

A trial test method is introduced to form and magnify regular interface. Through researching on the carbonation of the magnifying interfacial transition zone （ITZ）, the practical carbonation of the concrete can be simulated. Because the diffusion rate of CO2 in the ITZ is several times greater than that in the bulk paste, the diffusion rate and direction of CO2 will change and form a new carbonation front line. An interfacial effect zone caused by the ITZ will change the distribution of the complete carbonation zone and the partial carbonation zone. One of the important reasons for the formation of the partial carbonation zone was the existence of the interfacial effect zone. Consequently, the method mentioned in this paper provides a new way for researching on the microstructure of the cement based materials during the carbonation process.

INTERFACE AND PROPERTIES OF ALKALI-TREATED CARBON FIBRE REINFORCED CEMENT COMPOSITES

The surface of carbon fibre is studied which has been treated with heated sodium hydrate solution (NaOH) . It is found that the surface of carbon fibre is not corroded during the treatment. But at the same time, it is also found that after this treatment, a certain number of carbonyl groups (C O) and (-COOH or ?COONa) are produced on the treated surface of carbon fibre. When carbon fiber is mixed with cement paste, the above reactive groups will link with Ca+2 in the paste, which will result in an early stage hydration of cement in inter facial areas. In addition, the experiments show that the rheological properties of cement paste reinforced with alkali-treated carbon fibre differ greatly from that of untreated carbon fibre reinforced cement paste.

Unraveling the incompatibility mechanism of ethylene carbonate-based electrolytes in sodium metal anodes

Ethylene carbonate(EC)is widely used in lithium-ion batteries due to its optimal overall performance with satisfactory conductivity,relatively stable solid electrolyte interphase(SEI),and wide electrochemical window.EC is also the most widely used electrolyte solvent in sodium ion batteries.However,compared to lithium metal,sodium metal(Na)shows higher activity and reacts violently with EC-based electrolyte(NaPF_(6)as solute),which leads to the failure of sodium metal batteries(SMBs).Herein,we reveal the electrochemical instability mechanism of EC on sodium metal battery,and find that the com-bination of EC and NaPF_(6) is electrically reduced in sodium metal anode during charging,resulting in the reduction of the first coulombic efficiency,and the continuous consumption of electrolyte leads to the cell failure.To address the above issues,an additive modified linear carbonate-based electrolyte is provided as a substitute for EC based electrolytes.Specifically,ethyl methyl carbonate(EMC)and dimethyl carbon-ate(DMC)as solvents and fluoroethylene carbonate(FEC)as SEI-forming additive have been identified as the optimal solvent for NaFP_(6)based electrolyte and used in Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))/Na batteries.The batter-ies exhibit excellent capacity retention rate of about 80%over 1000 cycles at a cut-off voltage of 4.3 V.

Thermal Conductance of Cu and Carbon Nanotube Interface Enhanced by a Graphene Layer

Thermal conduetances between Cu and graphene covered carbon nanotubes （gCNTs） are calculated by molecular dynamics simulations. The results show that the thermal conductance is about ten times larger than that of Cu- CNT interface. The enhanced thermal conductance is due to the larger contact area introduced by the graphene layer and the stronger thermal transfer ability of the Cu-gCNT interface. From the linear increasing thermal conductance with the increasing total contact area, an effective contact area of such an interface can be defined.

Adsorption Behavior of a Water-soluble Porphyrin at the Glass-water Interface as Studied by Synchronous Total Internal Reflection Fluorescence Spectroscopy

Total internal reflection fluorescence spectroscopy (TIRF) and synchronous scanning technique were combined to study the adsorption behavior of the meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS) at the glass-water interface without any surfactant. The pH dependence of synchronous fluorescence signal at the interface was analyzed. Both unprotonated (TPPS4-) and diprotonated (H2TPPS2-) forms of TPPS were observed at the interface. But the interface favored the adsorption of. The apparent estimated pKa2 value shifted from 5.00 in the bulk solution to 2.7 at the interface. STIRF provides a good technique to study multi-component systems at the interface.

Interfacial Properties Modification of Carbon Fiber/Polyarylacetylene Composites

This work was dedicated to performing surface oxidation and coating treatments on carbon fibers （CF） and investigating the changes of fiber surface properties after these treatments, including surface composition, relative volume of functional groups, and surface topography with X-ray photoelectron spectroscopy （XPS） and atom force microscopy （AFM） technology. The results show that, after oxidation treatments, interfacial properties between CF and non-polar polyarylacetylene （PAA） resin are remarkably modified by removing weak surface layers and increasing fiber surface roughness. Coating treatment by high char phenolic resin solution after oxidation makes interface of CF/PAA composites to be upgraded and the interfacial properties further bettered.

Comparative study on the interface and mechanical properties of T700/Al and M40/Al composites

T700/Al and M40/Al composites were fabricated by squeeze casting technology, and their interface and mechanical properties were investigated comparatively. The results showed that both of the composites were dense, and the fibers were distributed uniformly in aluminum matrix. Aluminum carbide （Al4C3） was observed on the interface of the two carbon fiber-reinforced aluminum （Cf/Al） composites. There was little Al4C3 with a length of 300-500 nm and a width of 30-60 nm in the M40/Al composite, whereas there was a great deal of Al4C3 with a length of 200-400 nm and a width of 100-200 nm in the T700/Al composite, due to a higher graphitization of M40Cf than T700Cf. The M40/Al composite showed a much higher tensile strength than the TT00/Al composite, and it was related to interracial bonding between carbon fibers and aluminum matrices.