Magnesium-based anode materials have attracted significant attention in the energy storage domain because of their high theoretical capacities and low electrochemical potentials.However,in conventional electrolyte sys...Magnesium-based anode materials have attracted significant attention in the energy storage domain because of their high theoretical capacities and low electrochemical potentials.However,in conventional electrolyte systems,magnesium metal electrodes dynamically generate an ion-blocking surface layer,resulting in prominent voltage polarization,which severely limits their practical applications.In this study,ZIF-8/carbon nanotubes(CNTs)coatings were used to modify the anodes of magnesium batteries.Compared with the unaltered magnesium battery,the voltage lag time of the ZIF-8/CNTs coating was shortened from 4 s before modification to 0.26 s,and the battery impedance was lowered by two orders of magnitude.The duration of the discharge platform was increased from 4 h before modification to 6-10 h,the anode utilization rate was more than doubled,and the specific energy density was significantly enhanced compared with the battery before modification.The mechanism indicates that the ZIF-8/CNTs coating can limit the infiltration of corrosive substances,extend their transmission path,and offer more effective protection to the magnesium anode.The incorporation of CNTs improves the conductivity of the battery,and it significantly improves the electrochemical performance of the magnesium battery.展开更多
A Luttinger liquid is a theoretical model describing interacting electrons in one-dimensional(1D)conductors.While individual 1D conductors have shown interesting Luttinger-liquid behaviors such as spin-charge separati...A Luttinger liquid is a theoretical model describing interacting electrons in one-dimensional(1D)conductors.While individual 1D conductors have shown interesting Luttinger-liquid behaviors such as spin-charge separation and power-law spectral density,the more interesting phenomena predicted in coupled Luttinger liquids of neighboring 1D conductors have been rarely observed due to the difficulty in creating such structures.Recently,we have successfully grown close-packed carbon nanotube(CNT)arrays with uniform chirality,providing an ideal material system for studying the coupled Luttinger liquids.Here,we report on the observation of tunable hyperbolic plasmons in the coupled Luttinger liquids of CNT arrays using scanning near-field optical microscopy.These hyperbolic plasmons,resulting from the conductivity anisotropy in the CNT array,exhibit strong spatial confinement,in situ tunability,and a wide spectral range.Despite their hyperbolic wavefronts,the plasmon propagation in the axial direction still adheres to the Luttinger-liquid theory.Our work not only demonstrates a fascinating phenomenon in coupled Luttinger liquids for fundamental physics exploration,but also provides a highly confined and in situ tunable hyperbolic plasmon in close-packed CNT arrays for future nanophotonic devices and circuits.展开更多
Energy storage is a key factor in the drive for carbon neutrality and carbon nanotubes(CNTs)may have an important role in this.Their intrinsic sp2 covalent structure gives them excellent electrical conductivity,mechan...Energy storage is a key factor in the drive for carbon neutrality and carbon nanotubes(CNTs)may have an important role in this.Their intrinsic sp2 covalent structure gives them excellent electrical conductivity,mechanical strength,and chemical stability,making them suitable for many uses in energy storage,such as lithium-ion batteries(LIBs).Currently,their use in LIBs mainly focuses on conductive networks,current collectors,and dry electrodes.The review outlines advances in the use of CNTs in the cathodes and anodes of LIBs,especially in the electrode fabrication and mechanical sensors,as well as providing insights into their future development.展开更多
Carbon nanotubes(CNTs)have many excellent properties that make them ideally suited for use in lithium-ion batteries(LIBs).In this review,the recent research on applications of CNTs in LIBs,including their usage as fre...Carbon nanotubes(CNTs)have many excellent properties that make them ideally suited for use in lithium-ion batteries(LIBs).In this review,the recent research on applications of CNTs in LIBs,including their usage as freestanding anodes,conductive additives,and current collectors,are discussed.Challenges,strategies,and progress are analyzed by selecting typical examples.Particularly,when CNTs are used with relatively large mass fractions,the relevant interfacial electrochemistry in such a CNT-based electrode,which dictates the quality of the resulting solid-electrolyte interface,becomes a concern.Hence,in this review the different lithium-ion adsorption and insertion mechanisms inside and outside of CNTs are compared;the influence of not only CNT structural features(including their length,defect density,diameter,and wall thickness)but also the electrolyte composition on the solid-electrolyte interfacial reactions is analyzed in detail.Strategies to optimize the solid-solid interface between CNTs and the other solid components in various composite electrodes are also covered.By emphasizing the importance of such a structure-performance relationship,the merits and weaknesses of various applications of CNTs in various advanced LIBs are clarified.展开更多
The strategic dispersion of carbon nanotubes(CNTs)within triblock copolymer matrix is key to fabricating nanocomposites with the desired electrical properties.This study investigated the self-assembly and electrical b...The strategic dispersion of carbon nanotubes(CNTs)within triblock copolymer matrix is key to fabricating nanocomposites with the desired electrical properties.This study investigated the self-assembly and electrical behavior of a polystyrene-polybutadiene-polystyrene(SBS)matrix with CNTs of different aspect ratios using hybrid particle-field molecular dynamics simulations.Structural factor analysis of the nanocomposites indicated that CNTs with higher aspect ratios promoted the transition of the SBS matrix from a bicontinuous to a lamellar phase.The resistor network algorithm method showed that the electrical conductivity of SBS and CNTs nanocomposites was influenced by the interplay between the CNTs aspect ratios,concentrations,and domain sizes of the triblock copolymer SBS.Our research sheds light on the relationship between CNTs dispersion and the electrical behavior of SBS/CNTs nanocomposites,guiding the engineering of materials to achieve desired electrical properties through the modulation of CNTs aspect ratios and tailored sizing of triblock copolymer domains.展开更多
The features of additive manufacturing(AM)have made commercially pure titanium(CP-Ti)an attractive candidate material for biomedical implants.However,achieving high strength and ductility is challenging because of the...The features of additive manufacturing(AM)have made commercially pure titanium(CP-Ti)an attractive candidate material for biomedical implants.However,achieving high strength and ductility is challenging because of the columnar structures and fine martensite formation.This study investigated the effect of carbon nanotubes(CNTs)addition on the microstructure and mechanical properties of grade 1 CP-Ti(Gr-1)during the laser powder bed fusion(L-PBF)process.A minute amount of 0.2%mass fraction(wt%)CNTs addition resulted in a high yield strength of approximately 700 MPa and exceptional ductility of 25.7%.Therein,a portion of the CNTs dissolved in the matrix as solute atoms,contributing to solution strengthening,while others were transformed into Ti C_(x)through an in situ reaction with the Ti matrix.Furthermore,the addition of CNTs resulted in the formation of a larger fraction of equiaxed grains and increased the activity of basal and prismatic slip systems.Hence,Gr-1 with CNTs exhibited significantly increased ductility while maintaining a high strength comparable to that of Gr-1 without CNTs.The insights gained from this study provide a novel approach for designing strong and ductile Ti alloys for AM.展开更多
Interfacial solar evaporation,which captures solar energy and localizes the absorbed heat for water evaporation,is considered a promising technology for seawater desalination and solar energy conversion.However,it is ...Interfacial solar evaporation,which captures solar energy and localizes the absorbed heat for water evaporation,is considered a promising technology for seawater desalination and solar energy conversion.However,it is currently limited by its low photothermal conversion efficiency,salt accumulation,and poor reliability.Herein,inspired by human intestinal villi structure,we design and fabricate a novel intestinal villi-like nitrogen-doped carbon nanotubes solar steam generator(N-CNTs SSG)consisting of three-dimensional(3D)hierarchical carbon nanotube matrices for ultrahigh solar evaporation efficiency.The 3D matrices with radial direction nitrogen-doped carbon nanotube clusters achieve ultrahigh surface area,photothermal efficiency,and hydrophilicity,which significantly intensifies the whole interfacial solar evaporation process.The new solar evaporation efficiency reaches as high as 96.8%.Furthermore,our ab initio molecular dynamics simulation reveals that N-doped carbon nanotubes exhibit a greater number of electronic states in close proximity to the Fermi level when compared to pristine carbon nanotubes.The outstanding absorptivity in the full solar spectrum and high solar altitude angles of the 3D hierarchical carbon nanotube matrices offer great potential to enable ultrahigh photothermal conversion under all-day and all-season circumstances.展开更多
The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compressio...The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of aggregates.The mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically analyzed.The results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,respectively.However,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the aggregates.Theσ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite trend.Theε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse aggregates.With increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.展开更多
Aqueous zinc ion batteries are regarded as one of the most promising candidates for large-scale energy stor-age due to their high safety,cost-effectiveness,and environ-mental friendliness.However,uncontrolled zinc den...Aqueous zinc ion batteries are regarded as one of the most promising candidates for large-scale energy stor-age due to their high safety,cost-effectiveness,and environ-mental friendliness.However,uncontrolled zinc dendrite growth and side reactions of the zinc anode decrease the sta-bility of Zn batteries.We report the synthesis of an air-oxid-ized carbon nanotube(O-CNT)film by chemical vapor de-position followed by heat treatment in air which is used as a protective layer on the Zn foil to suppress zinc dendrite growth.The increase in the hydrophilicity of the O-CNT film caused by air oxidation facilitates zinc deposition between the film and the anode instead of deposition on the film surface.The porous structure of the O-CNT film homogenizes the Zn^(2+)ion flux and the electric field on the surface of the Zn foil,leading to the uniform deposition of Zn.As a result,a O-CNT@Zn symmetric cell has a much better cycling stability with a life of more than 3000 h at 1 mA cm^(−2) with a capacity of 1 mAh cm^(−2),and values of more than 2000 h and 1 mAh cm^(−2) at 5 mA cm^(−2).In addition,a O-CNT@Zn||Mn^(2+)inserted hydrated vanadium pentoxide(MnVOH)full cell has a better rate per-formance than a Zn||MnVOH cell,achieving a high discharge capacity of 194 mAh g^(−1) at a high current density of 8 A g^(−1).In a long-term cycling test,the O-CNT@Zn||MnVOH full cell has a capacity retention of 58.8%after 2000 cycles at a current density of 5 A·g^(−1).展开更多
Carbon nanotubes(CNTs)supported CoB and CoBSn catalysts were synthesized for hydrogen production via NaBH4 hydrolysis.The roles of Sn-promoter and the effect of CNTs treatment on CoB catalysts were evaluated and discu...Carbon nanotubes(CNTs)supported CoB and CoBSn catalysts were synthesized for hydrogen production via NaBH4 hydrolysis.The roles of Sn-promoter and the effect of CNTs treatment on CoB catalysts were evaluated and discussed.It is found that after the addition of Sn promoter,the specific surface area and the generation of active CoB phase are increased,while the oxidation treatment of CNTs results in more loading amounts of active components and enrichment of electron at active sites as well as large surface area.Consequently,the Sn-doped CoB catalysts supported on CNTs with oxidation treatment exhibits a significantly improved activity with a high H_(2)generation rate of 2640 mL/(min·g).Meanwhile,this catalyst shows a low activation energy of 43.7 kJ/mol and relatively high reusability.展开更多
Carbon nanotube formation exemplifies atomically precise self-assembly,where atomic interactions dynamically engineer nanoscale architectures with emergent properties that transcend classical material boundaries.Howev...Carbon nanotube formation exemplifies atomically precise self-assembly,where atomic interactions dynamically engineer nanoscale architectures with emergent properties that transcend classical material boundaries.However,elucidating the transient molecular intermediates remains a critical mechanistic frontier.This study investigates the atomic-scale nucleation process of single-walled carbon nanotubes(SWCNTs)from acetylene on iron(Fe)clusters,utilizing GFN(-x)TB-based nanoreactor molecular dynamics simulations.The simulations reveal a consistent nucleation pathway,regardless of iron cluster size(Fe_(13),Fe_(38),Fe_(55)),where the chemisorption and dissociation of acetylene molecules on the Fe clusters lead to the formation of C_(2)H and C_(2)intermediates.These species then undergo oligomerization,initiating the growth of carbon chains.As the chains cross-link and cyclize,five-membered carbon rings are preferentially formed,which eventually evolve into six-membered rings and more complex sp2-hybridized carbon networks,resembling the cap structures of nascent SWCNTs.Although the nucleation mechanism remains similar across all cluster sizes,larger clusters show enhanced catalytic activity,leading to higher molecular weight hydrocarbons and more extensive carbocyclic networks due to their higher density of active sites per reacting molecule.Crucially,the study highlights the role of C_(2)H as the key active species in the carbon network formation process.These findings offer critical insights into the initial stages of SWCNT nucleation,contributing to a deeper understanding of the mechanisms driving SWCNT growth and guiding the development of optimized synthetic strategies.展开更多
For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of e...For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of electrical conductivity and structural stability in the electrode materials during electrochemical cycling.We report the production of a novel flexible electrode material,by anchoring MnO_(2) nanosheets on a B,N co-doped carbon nanotube ar-ray(BNCNTs)grown on carbon cloth(BNCNTs@MnO_(2)),which was fabricated by in-situ pyrolysis and hydrothermal growth.The generated BNCNTs were strongly bonded to the surface of the car-bon fibers in the carbon cloth which provides both excellent elec-tron transport and ion diffusion,and improves the stability and dur-ability of the cathode.Importantly,the BNCNTs offer more active sites for the hydrothermal growth of MnO_(2),ensuring a uniform dis-tribution.Electrochemical tests show that BNCNTs@MnO_(2) delivers a high specific capacity of 310.7 mAh g^(−1) at 0.1 A g^(−1),along with excellent rate capability and outstanding cycling stability,with a 79.7% capacity retention after 8000 cycles at 3 A g^(−1).展开更多
Carbon nanotubes(CNTs)have garnered great attention in recent years due to their outstanding electrical,thermal,and mechanical properties.The incorporation of small amounts of CNTs in polymers can substantially improv...Carbon nanotubes(CNTs)have garnered great attention in recent years due to their outstanding electrical,thermal,and mechanical properties.The incorporation of small amounts of CNTs in polymers can substantially improve the sensitivity of the polymer's electrical conductivity.This paper presents a modified Maxwell model to evaluate the electrical conductivity of CNTs-filled polymer composites by introducing a transition zone to account for the tunneling effect.In this modified Maxwell model,the CNTs-filled polymer composite is modeled as a three-phase composite,consisting of a matrix(polymer),inclusions(CNTs),and a transition zone(tunneling zone).The effective electrical conductivity(EEC)of the composite is calculated based on the volume fractions and electrical conductivities of the matrix,inclusions,and transition zone.The model's validity is confirmed through the use of available test data,which demonstrates its capability to accurately capture the nonlinear conductivity behavior observed in CNTs-polymer composites.This study offers valuable insights into the design of high-performance conductive polymer nanocomposites,and enhances the understanding of electrical conduction mechanisms in CNT-dispersed polymer composites.展开更多
Enhancing A.bisporus L.culture media with nanomaterials and some biostimulants is important for in improving mushroom productivity quantitatively and qualitatively.Magnetic iron nanoparticles(N-FeO),carbon nanotube(CN...Enhancing A.bisporus L.culture media with nanomaterials and some biostimulants is important for in improving mushroom productivity quantitatively and qualitatively.Magnetic iron nanoparticles(N-FeO),carbon nanotube(CNTs)suspensions,effective microorganisms(EM)bio-fertilisers,and growth stimulants(Atonik)were used individually and in combination to enhance the compost culture media.Quantitative and qualitative traits of the mushroom yield were measured.In a simple oOne-Wway experiment that included 16 treatments—Ssingle agents,two-,three-,and four-way Ccombinations and three replications—,the statistical analysis results of Duncan’'s test showed.Tthat the individual impact of the applied study treatments and their combined synergistic effects resulted in a significant increase in the traits of the number of fruiting bodies,fruiting body rate,yield quantity,mushroom biological efficiency ratio,stem length,stem diameter,head diameter,head thickness,carbohydrates content,protein content,ash,and dry matter.The application of Atonik itself resulted in the highest values of fruiting body number,yield,biological efficiency,and stem length,which were respectively were 128.33 body bags^(-1),2814 g bag-1,37.52%,and 3.03 cm,compared to the control of 32.33 body bags^(-1),749 g bag-1,9.98%,and 1.72 cm.The treatments NFeO+CNT+EM+ATO resulted in a significant increase in the traits of the fruiting body rate,stem length,and carbohydrate content by 32.69 g,3.40 cm,and 16.78%,respectively,compared to the control of 22.97 g,1.72 cm,and 8.16%,respectively.展开更多
The edible mushroom Agaricus bisporus L.plays a crucial ecological role in nutrient cycling and organic matter decomposition,alongside its increasing importance in the food and nutrition industry.This study explored e...The edible mushroom Agaricus bisporus L.plays a crucial ecological role in nutrient cycling and organic matter decomposition,alongside its increasing importance in the food and nutrition industry.This study explored ecological interventions to enhance the mushroom’s vitamin content by enriching its cultivation substrate with nanomaterials and biostimulatory agents.The experiment was conducted within the mushroom production project at Al-Qadisiyah Governorate,Iraq.The compost-based medium was amended with magnetic iron nanoparticles(N-FeO),carbon nanotube(CNT)suspensions,EM biofertilizer,and Atonik growth stimulant.Their ecological impact on the enrichment of fat-soluble(A,D,E)and water-soluble(B2,B3,B5,B6)vitamins in mushrooms was assessed.The study employed a Completely Randomized Design(CRD)with three replicates.Results revealed that the synergistic application of these eco-friendly treatments significantly enhanced the vitamin profiles of A.bisporus.The highest concentrations of vitamins B2 and B5(5.16 and 17.70 mg kg^(-1),respectively)and vitamin A(6.87 IU ml^(-1))were recorded under the combined quadruple treatment.Additionally,the triple treatment(N-FeO+EM+Atonik)notably increased levels of vitamins B2(4.47 mg kg^(-1)),B6(25.66 mg kg^(-1)),D(34.76 mg kg^(-1)),and vitamin A(6.87 IU ml^(-1)).Dual treatments(EM+Atonik)also significantly improved vitamin B2(4.54 mg kg^(-1))and vitamin E(3.30 mg kg^(-1))contents.These findings demonstrate that integrating nanomaterials and biostimulants can serve as an ecological strategy to improve the nutritional quality of mushrooms while promoting sustainable agricultural practices.展开更多
With the increasing prevalence of lithium-ion batteries(LIBs)applications,the demand for high-capacity next-generation materials has also increased.SiO_(x)is currently considered a promising anode material due to its ...With the increasing prevalence of lithium-ion batteries(LIBs)applications,the demand for high-capacity next-generation materials has also increased.SiO_(x)is currently considered a promising anode material due to its exceptionally high capacity for LIBs.However,the significant volumetric changes of SiO_(x)during cycling and its initial Coulombic efficiency(ICE)complicate its use,whether alone or in combination with graphite materials.In this study,a three-dimensional conductive binder network with high electronic conductivity and robust elasticity for graphite/SiO_(x)blended anodes was proposed by chemically anchoring carbon nanotubes and carboxymethyl cellulose binders using tannic acid as a chemical cross-linker.In addition,a dehydrogenation-based prelithiation strategy employing lithium hydride was utilized to enhance the ICE of SiO_(x).The combination of these two strategies increased the CE of SiO_(x)from 74%to87%and effectively mitigated its volume expansion in the graphite/SiO_(x)blended electrode,resulting in an efficient electron-conductive binder network.This led to a remarkable capacity retention of 94%after30 cycles,even under challenging conditions,with a high capacity of 550 mA h g^(-1)and a current density of 4 mA cm^(-2).Furthermore,to validate the feasibility of utilizing prelithiated SiO_(x)anode materials and the conductive binder network in LIBs,a full cell incorporating these materials and a single-crystalline Ni-rich cathode was used.This cell demonstrated a~27.3%increase in discharge capacity of the first cycle(~185.7 mA h g^(-1))and exhibited a cycling stability of 300 cycles.Thus,this study reports a simple,feasible,and insightful method for designing high-performance LIB electrodes.展开更多
Carbon nanotubes are uniquely featured by the nanoscale tubular structure with a highly-curved surface and defined chirality.The diameter and chirality fundamentally determine their stability and electrical and therma...Carbon nanotubes are uniquely featured by the nanoscale tubular structure with a highly-curved surface and defined chirality.The diameter and chirality fundamentally determine their stability and electrical and thermal properties.Up to now,the relationship between the intrinsic thermal conductivity and the atomic features of CNTs has not been established,due to the challenges in precise measurements and characterizations.In this work,we develop a micro electro-thermal device enabling simultaneous thermal measurements by Raman spectroscopy and atomic structural characterization by transmission electron microscopy for individual CNTs.The influence of diameter and chirality is systematically investigated.In addition,the temperature dependence of the thermal conductivity was extracted from parameter optimization of finite-element modeling.It is found that the thermal transport of CNTs depends mainly on the diameter,while the chiral angle has no significant influence.Along with increasing diameter,the room temperature thermal conductivity increases and eventually approaches the limit of flat graphene.展开更多
Carbon nanotubes(CNTs)reinforced copper(CNTs/Cu)is one of the most promising and extensively researched materials for replacing traditional Cu-based materials in high-load and high-current applications,particularly wi...Carbon nanotubes(CNTs)reinforced copper(CNTs/Cu)is one of the most promising and extensively researched materials for replacing traditional Cu-based materials in high-load and high-current applications,particularly within the aerospace industry.Amorphous carbon nanotubes(aCNTs)are a type of carbon nanotubes characterized by the presence of mesopores distributed across their amorphous sidewalls,facilitating connectivity between the hollow core and the external environment.Therefore,we propose utilizing aCNTs as a reinforcing agent for Cu.The mesoporous structure of aCNTs facilitates the interpenetration of Cu into the aCNTs,thereby maintaining the continuity of the matrix properties.Experimental results demonstrate that Cu effectively penetrates the mesoporous sidewalls of aCNTs.Both pure Cu and aCNTs-reinforced Cu exhibit comparable electrical conductivity,while the hardness of the aCNTs/Cu composite is significantly enhanced.Additionally,both the density and porosity of aCNTs/Cu are lower than those of pure Cu,and the introduction of aCNTs helps to reduce the sintering temperature.展开更多
Bipolar plates(BPs)are essential multifunctional components in vanadium redox flow batteries(VRFBs)that require excellent electrical conductivity,low permeability,and strong solid support for the stack.However,convent...Bipolar plates(BPs)are essential multifunctional components in vanadium redox flow batteries(VRFBs)that require excellent electrical conductivity,low permeability,and strong solid support for the stack.However,conventional BPs are based on graphite sheets,which provide mechanical properties and corrosion resistance but have limitations in terms of electrical conductivity.Although carbon nanotubes(CNTs)have excellent properties,CNT composites with low CNT volume fractions(10–20%)have increased electrolyte permeability and limited electrical conductivity improvement,resulting in low durability and efficiency for VRFBs.This study proposes a novel concept of horizontally aligned CNT nanocomposite bipolar plate(HACN-BP)to address these issues.The HACN-BPs feature an optimized conduction path with a CNT volume fraction of 59%,resulting in reduced manufacturing time while demonstrating superior conductivity and permeability compared to conventional BPs.Furthermore,integrated HACN-BP mitigates ohmic loss that occurs in the BPs,thereby mitigating the potential drop by 40%.Therefore,the utilization of HACN-BP shows superior performance compared to recent studies,a substantial improvement of more than 6%in energy efficiency and 14%in capacity over conventional BP.展开更多
In this study,we present a self-driven photoelectrocatalytic(SD-PEC)system that effectively treats complex uranium-bearing wastewaters for both uranium recovery and organic matter decomposition while generating power....In this study,we present a self-driven photoelectrocatalytic(SD-PEC)system that effectively treats complex uranium-bearing wastewaters for both uranium recovery and organic matter decomposition while generating power.The system utilizes a titanium dioxide nanorod array(TNR)photoelectrode coupled with a silicon solar cell to optimize electron transport,while the cathode is composed of a carbon fiber coated with carboxylated carbon nanotubes(CCNT/CF),which efficiently reduce UO_(2)^(2+).The results demonstrate significant removal efficiency of uranium(complete removal in 25 min at a rate constant of~0.248 min^(-1)),as well as substantial degradation of organic impurities.Furthermore,the system generates sufficient power output to light an LED lamp and exhibits superior performance under various complex wastewater conditions,including simulated seawater and real uranium tailings wastewater.These findings underscore the potential of the SD-PEC system as a versatile approach for sustainable treatment and energy recovery of radioactive wastewater.The significance of this research extends to global environmental challenges,offering an innovative solution for managing radioactive wastewater while simultaneously contributing to renewable energy generation.展开更多
基金supported by the Guangxi Natural Science Foundation,China(No.2020GXNSFAA 159011)the National Natural Science Foundation of China(No.51664011).
文摘Magnesium-based anode materials have attracted significant attention in the energy storage domain because of their high theoretical capacities and low electrochemical potentials.However,in conventional electrolyte systems,magnesium metal electrodes dynamically generate an ion-blocking surface layer,resulting in prominent voltage polarization,which severely limits their practical applications.In this study,ZIF-8/carbon nanotubes(CNTs)coatings were used to modify the anodes of magnesium batteries.Compared with the unaltered magnesium battery,the voltage lag time of the ZIF-8/CNTs coating was shortened from 4 s before modification to 0.26 s,and the battery impedance was lowered by two orders of magnitude.The duration of the discharge platform was increased from 4 h before modification to 6-10 h,the anode utilization rate was more than doubled,and the specific energy density was significantly enhanced compared with the battery before modification.The mechanism indicates that the ZIF-8/CNTs coating can limit the infiltration of corrosive substances,extend their transmission path,and offer more effective protection to the magnesium anode.The incorporation of CNTs improves the conductivity of the battery,and it significantly improves the electrochemical performance of the magnesium battery.
基金supported by the National Key R&D Program of China(Grant No.2021YFA1202902)the National Natural Science Foundation of China(Grant Nos.12374292 and 12074244)B.L.acknowledges support from the Development Scholarship for Outstanding Ph.D.of Shanghai Jiao Tong University.J.K.acknowledges support from the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(Grant No.NRF-RS-2024-00454528).
文摘A Luttinger liquid is a theoretical model describing interacting electrons in one-dimensional(1D)conductors.While individual 1D conductors have shown interesting Luttinger-liquid behaviors such as spin-charge separation and power-law spectral density,the more interesting phenomena predicted in coupled Luttinger liquids of neighboring 1D conductors have been rarely observed due to the difficulty in creating such structures.Recently,we have successfully grown close-packed carbon nanotube(CNT)arrays with uniform chirality,providing an ideal material system for studying the coupled Luttinger liquids.Here,we report on the observation of tunable hyperbolic plasmons in the coupled Luttinger liquids of CNT arrays using scanning near-field optical microscopy.These hyperbolic plasmons,resulting from the conductivity anisotropy in the CNT array,exhibit strong spatial confinement,in situ tunability,and a wide spectral range.Despite their hyperbolic wavefronts,the plasmon propagation in the axial direction still adheres to the Luttinger-liquid theory.Our work not only demonstrates a fascinating phenomenon in coupled Luttinger liquids for fundamental physics exploration,but also provides a highly confined and in situ tunable hyperbolic plasmon in close-packed CNT arrays for future nanophotonic devices and circuits.
文摘Energy storage is a key factor in the drive for carbon neutrality and carbon nanotubes(CNTs)may have an important role in this.Their intrinsic sp2 covalent structure gives them excellent electrical conductivity,mechanical strength,and chemical stability,making them suitable for many uses in energy storage,such as lithium-ion batteries(LIBs).Currently,their use in LIBs mainly focuses on conductive networks,current collectors,and dry electrodes.The review outlines advances in the use of CNTs in the cathodes and anodes of LIBs,especially in the electrode fabrication and mechanical sensors,as well as providing insights into their future development.
基金Xiamen Science and Technology Project,Grant/Award Number:3502Z20231057National Key Research and Development Program of China,Grant/Award Number:3502Z20231057National Natural Science Foundation of China,Grant/Award Numbers:22279107,22288102。
文摘Carbon nanotubes(CNTs)have many excellent properties that make them ideally suited for use in lithium-ion batteries(LIBs).In this review,the recent research on applications of CNTs in LIBs,including their usage as freestanding anodes,conductive additives,and current collectors,are discussed.Challenges,strategies,and progress are analyzed by selecting typical examples.Particularly,when CNTs are used with relatively large mass fractions,the relevant interfacial electrochemistry in such a CNT-based electrode,which dictates the quality of the resulting solid-electrolyte interface,becomes a concern.Hence,in this review the different lithium-ion adsorption and insertion mechanisms inside and outside of CNTs are compared;the influence of not only CNT structural features(including their length,defect density,diameter,and wall thickness)but also the electrolyte composition on the solid-electrolyte interfacial reactions is analyzed in detail.Strategies to optimize the solid-solid interface between CNTs and the other solid components in various composite electrodes are also covered.By emphasizing the importance of such a structure-performance relationship,the merits and weaknesses of various applications of CNTs in various advanced LIBs are clarified.
基金financially supported by the National Natural Science Foundation of China(Nos.52273019,62173065,22133002,22273031,and 12274056)Fundamental Research Funds for the Central Universities(No.04442024074)+2 种基金NationalKey R&D Program of China(No.2022YFB3707300)Beijing Natural Science Foundation(No.4242040)Scientific Research Funds Project of Liaoning Provincial Department of Education(No.LJKZ0034)。
文摘The strategic dispersion of carbon nanotubes(CNTs)within triblock copolymer matrix is key to fabricating nanocomposites with the desired electrical properties.This study investigated the self-assembly and electrical behavior of a polystyrene-polybutadiene-polystyrene(SBS)matrix with CNTs of different aspect ratios using hybrid particle-field molecular dynamics simulations.Structural factor analysis of the nanocomposites indicated that CNTs with higher aspect ratios promoted the transition of the SBS matrix from a bicontinuous to a lamellar phase.The resistor network algorithm method showed that the electrical conductivity of SBS and CNTs nanocomposites was influenced by the interplay between the CNTs aspect ratios,concentrations,and domain sizes of the triblock copolymer SBS.Our research sheds light on the relationship between CNTs dispersion and the electrical behavior of SBS/CNTs nanocomposites,guiding the engineering of materials to achieve desired electrical properties through the modulation of CNTs aspect ratios and tailored sizing of triblock copolymer domains.
基金financially supported by the National Key Research and Development Project of the Ministry of Science and Technology of China(No.2022YFB4601000)the Fundamental Research Funds for the Central Universities(No.2042023kf0103)the Ministry of Trade,Industry and Energy,Korea(No.20013095)。
文摘The features of additive manufacturing(AM)have made commercially pure titanium(CP-Ti)an attractive candidate material for biomedical implants.However,achieving high strength and ductility is challenging because of the columnar structures and fine martensite formation.This study investigated the effect of carbon nanotubes(CNTs)addition on the microstructure and mechanical properties of grade 1 CP-Ti(Gr-1)during the laser powder bed fusion(L-PBF)process.A minute amount of 0.2%mass fraction(wt%)CNTs addition resulted in a high yield strength of approximately 700 MPa and exceptional ductility of 25.7%.Therein,a portion of the CNTs dissolved in the matrix as solute atoms,contributing to solution strengthening,while others were transformed into Ti C_(x)through an in situ reaction with the Ti matrix.Furthermore,the addition of CNTs resulted in the formation of a larger fraction of equiaxed grains and increased the activity of basal and prismatic slip systems.Hence,Gr-1 with CNTs exhibited significantly increased ductility while maintaining a high strength comparable to that of Gr-1 without CNTs.The insights gained from this study provide a novel approach for designing strong and ductile Ti alloys for AM.
基金Funding information National Natural Science Foundation of China,Grant/Award Numbers:52476072,51936005Young Talent Support Project of Guangzhou Association for Science and Technology+1 种基金Guangdong Basic and Applied Basic Research Foundation(No.2024A1515030035)Guangdong Pro vincial University Innovation Team Project(No.2023KCXTD038)。
文摘Interfacial solar evaporation,which captures solar energy and localizes the absorbed heat for water evaporation,is considered a promising technology for seawater desalination and solar energy conversion.However,it is currently limited by its low photothermal conversion efficiency,salt accumulation,and poor reliability.Herein,inspired by human intestinal villi structure,we design and fabricate a novel intestinal villi-like nitrogen-doped carbon nanotubes solar steam generator(N-CNTs SSG)consisting of three-dimensional(3D)hierarchical carbon nanotube matrices for ultrahigh solar evaporation efficiency.The 3D matrices with radial direction nitrogen-doped carbon nanotube clusters achieve ultrahigh surface area,photothermal efficiency,and hydrophilicity,which significantly intensifies the whole interfacial solar evaporation process.The new solar evaporation efficiency reaches as high as 96.8%.Furthermore,our ab initio molecular dynamics simulation reveals that N-doped carbon nanotubes exhibit a greater number of electronic states in close proximity to the Fermi level when compared to pristine carbon nanotubes.The outstanding absorptivity in the full solar spectrum and high solar altitude angles of the 3D hierarchical carbon nanotube matrices offer great potential to enable ultrahigh photothermal conversion under all-day and all-season circumstances.
基金financially supported by the National Natural Science Foundation of China(Nos.52174092,51904290,and 52374147)the Natural Science Foundation of Jiangsu Province,China(No.BK20220157)+2 种基金the Fundamental Research Funds for the Central Universities,China(No.2022YCPY0202)the National Key Research and Development Program of China(No.2023YFC3804204)the Major Program of Xinjiang Uygur Autonomous Region S cience and Technology(No.2023A01002)。
文摘The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of aggregates.The mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically analyzed.The results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,respectively.However,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the aggregates.Theσ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite trend.Theε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse aggregates.With increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.
基金supported by the National Natural Science Foundation of China(22179093 and21905202)。
文摘Aqueous zinc ion batteries are regarded as one of the most promising candidates for large-scale energy stor-age due to their high safety,cost-effectiveness,and environ-mental friendliness.However,uncontrolled zinc dendrite growth and side reactions of the zinc anode decrease the sta-bility of Zn batteries.We report the synthesis of an air-oxid-ized carbon nanotube(O-CNT)film by chemical vapor de-position followed by heat treatment in air which is used as a protective layer on the Zn foil to suppress zinc dendrite growth.The increase in the hydrophilicity of the O-CNT film caused by air oxidation facilitates zinc deposition between the film and the anode instead of deposition on the film surface.The porous structure of the O-CNT film homogenizes the Zn^(2+)ion flux and the electric field on the surface of the Zn foil,leading to the uniform deposition of Zn.As a result,a O-CNT@Zn symmetric cell has a much better cycling stability with a life of more than 3000 h at 1 mA cm^(−2) with a capacity of 1 mAh cm^(−2),and values of more than 2000 h and 1 mAh cm^(−2) at 5 mA cm^(−2).In addition,a O-CNT@Zn||Mn^(2+)inserted hydrated vanadium pentoxide(MnVOH)full cell has a better rate per-formance than a Zn||MnVOH cell,achieving a high discharge capacity of 194 mAh g^(−1) at a high current density of 8 A g^(−1).In a long-term cycling test,the O-CNT@Zn||MnVOH full cell has a capacity retention of 58.8%after 2000 cycles at a current density of 5 A·g^(−1).
基金supported by National Natural Science Foundation of China(22276144).
文摘Carbon nanotubes(CNTs)supported CoB and CoBSn catalysts were synthesized for hydrogen production via NaBH4 hydrolysis.The roles of Sn-promoter and the effect of CNTs treatment on CoB catalysts were evaluated and discussed.It is found that after the addition of Sn promoter,the specific surface area and the generation of active CoB phase are increased,while the oxidation treatment of CNTs results in more loading amounts of active components and enrichment of electron at active sites as well as large surface area.Consequently,the Sn-doped CoB catalysts supported on CNTs with oxidation treatment exhibits a significantly improved activity with a high H_(2)generation rate of 2640 mL/(min·g).Meanwhile,this catalyst shows a low activation energy of 43.7 kJ/mol and relatively high reusability.
基金supported by the National Key R&D Program of China(2022YFA1604100)the National Natural Science Foundation of China(22302220,22372187,1972157,21972160,22402218)+2 种基金the National Science Fund for Distinguished Young Scholars of China(22225206)the Fundamental Research Program of Shanxi Province(202203021222403)the Youth Innovation Promotion Association CAS(2020179)。
文摘Carbon nanotube formation exemplifies atomically precise self-assembly,where atomic interactions dynamically engineer nanoscale architectures with emergent properties that transcend classical material boundaries.However,elucidating the transient molecular intermediates remains a critical mechanistic frontier.This study investigates the atomic-scale nucleation process of single-walled carbon nanotubes(SWCNTs)from acetylene on iron(Fe)clusters,utilizing GFN(-x)TB-based nanoreactor molecular dynamics simulations.The simulations reveal a consistent nucleation pathway,regardless of iron cluster size(Fe_(13),Fe_(38),Fe_(55)),where the chemisorption and dissociation of acetylene molecules on the Fe clusters lead to the formation of C_(2)H and C_(2)intermediates.These species then undergo oligomerization,initiating the growth of carbon chains.As the chains cross-link and cyclize,five-membered carbon rings are preferentially formed,which eventually evolve into six-membered rings and more complex sp2-hybridized carbon networks,resembling the cap structures of nascent SWCNTs.Although the nucleation mechanism remains similar across all cluster sizes,larger clusters show enhanced catalytic activity,leading to higher molecular weight hydrocarbons and more extensive carbocyclic networks due to their higher density of active sites per reacting molecule.Crucially,the study highlights the role of C_(2)H as the key active species in the carbon network formation process.These findings offer critical insights into the initial stages of SWCNT nucleation,contributing to a deeper understanding of the mechanisms driving SWCNT growth and guiding the development of optimized synthetic strategies.
基金financial support from projects funded by the National Natural Science Foundation of China(52172038,22179017)the National Key Research and Development Program of China(2022YFB4101600,2022YFB4101601)。
文摘For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of electrical conductivity and structural stability in the electrode materials during electrochemical cycling.We report the production of a novel flexible electrode material,by anchoring MnO_(2) nanosheets on a B,N co-doped carbon nanotube ar-ray(BNCNTs)grown on carbon cloth(BNCNTs@MnO_(2)),which was fabricated by in-situ pyrolysis and hydrothermal growth.The generated BNCNTs were strongly bonded to the surface of the car-bon fibers in the carbon cloth which provides both excellent elec-tron transport and ion diffusion,and improves the stability and dur-ability of the cathode.Importantly,the BNCNTs offer more active sites for the hydrothermal growth of MnO_(2),ensuring a uniform dis-tribution.Electrochemical tests show that BNCNTs@MnO_(2) delivers a high specific capacity of 310.7 mAh g^(−1) at 0.1 A g^(−1),along with excellent rate capability and outstanding cycling stability,with a 79.7% capacity retention after 8000 cycles at 3 A g^(−1).
基金Project supported by the National Natural Science Foundation of China(Nos.11972203 and 11572162)the Science and Technology Innovation 2025 Major Project of Ningbo City of China(No.2022Z209)Ningbo Key Technology Breakthrough Plan Project of“Science and Technology Innovation Yongjiang 2035”(No.2024Z256)。
文摘Carbon nanotubes(CNTs)have garnered great attention in recent years due to their outstanding electrical,thermal,and mechanical properties.The incorporation of small amounts of CNTs in polymers can substantially improve the sensitivity of the polymer's electrical conductivity.This paper presents a modified Maxwell model to evaluate the electrical conductivity of CNTs-filled polymer composites by introducing a transition zone to account for the tunneling effect.In this modified Maxwell model,the CNTs-filled polymer composite is modeled as a three-phase composite,consisting of a matrix(polymer),inclusions(CNTs),and a transition zone(tunneling zone).The effective electrical conductivity(EEC)of the composite is calculated based on the volume fractions and electrical conductivities of the matrix,inclusions,and transition zone.The model's validity is confirmed through the use of available test data,which demonstrates its capability to accurately capture the nonlinear conductivity behavior observed in CNTs-polymer composites.This study offers valuable insights into the design of high-performance conductive polymer nanocomposites,and enhances the understanding of electrical conduction mechanisms in CNT-dispersed polymer composites.
文摘Enhancing A.bisporus L.culture media with nanomaterials and some biostimulants is important for in improving mushroom productivity quantitatively and qualitatively.Magnetic iron nanoparticles(N-FeO),carbon nanotube(CNTs)suspensions,effective microorganisms(EM)bio-fertilisers,and growth stimulants(Atonik)were used individually and in combination to enhance the compost culture media.Quantitative and qualitative traits of the mushroom yield were measured.In a simple oOne-Wway experiment that included 16 treatments—Ssingle agents,two-,three-,and four-way Ccombinations and three replications—,the statistical analysis results of Duncan’'s test showed.Tthat the individual impact of the applied study treatments and their combined synergistic effects resulted in a significant increase in the traits of the number of fruiting bodies,fruiting body rate,yield quantity,mushroom biological efficiency ratio,stem length,stem diameter,head diameter,head thickness,carbohydrates content,protein content,ash,and dry matter.The application of Atonik itself resulted in the highest values of fruiting body number,yield,biological efficiency,and stem length,which were respectively were 128.33 body bags^(-1),2814 g bag-1,37.52%,and 3.03 cm,compared to the control of 32.33 body bags^(-1),749 g bag-1,9.98%,and 1.72 cm.The treatments NFeO+CNT+EM+ATO resulted in a significant increase in the traits of the fruiting body rate,stem length,and carbohydrate content by 32.69 g,3.40 cm,and 16.78%,respectively,compared to the control of 22.97 g,1.72 cm,and 8.16%,respectively.
文摘The edible mushroom Agaricus bisporus L.plays a crucial ecological role in nutrient cycling and organic matter decomposition,alongside its increasing importance in the food and nutrition industry.This study explored ecological interventions to enhance the mushroom’s vitamin content by enriching its cultivation substrate with nanomaterials and biostimulatory agents.The experiment was conducted within the mushroom production project at Al-Qadisiyah Governorate,Iraq.The compost-based medium was amended with magnetic iron nanoparticles(N-FeO),carbon nanotube(CNT)suspensions,EM biofertilizer,and Atonik growth stimulant.Their ecological impact on the enrichment of fat-soluble(A,D,E)and water-soluble(B2,B3,B5,B6)vitamins in mushrooms was assessed.The study employed a Completely Randomized Design(CRD)with three replicates.Results revealed that the synergistic application of these eco-friendly treatments significantly enhanced the vitamin profiles of A.bisporus.The highest concentrations of vitamins B2 and B5(5.16 and 17.70 mg kg^(-1),respectively)and vitamin A(6.87 IU ml^(-1))were recorded under the combined quadruple treatment.Additionally,the triple treatment(N-FeO+EM+Atonik)notably increased levels of vitamins B2(4.47 mg kg^(-1)),B6(25.66 mg kg^(-1)),D(34.76 mg kg^(-1)),and vitamin A(6.87 IU ml^(-1)).Dual treatments(EM+Atonik)also significantly improved vitamin B2(4.54 mg kg^(-1))and vitamin E(3.30 mg kg^(-1))contents.These findings demonstrate that integrating nanomaterials and biostimulants can serve as an ecological strategy to improve the nutritional quality of mushrooms while promoting sustainable agricultural practices.
基金supported by the National Research Foundation(NRF)of Korea grant funded by the Korean government(MSIT)(No.NRF-2021 M3 H4A1A02045962).
文摘With the increasing prevalence of lithium-ion batteries(LIBs)applications,the demand for high-capacity next-generation materials has also increased.SiO_(x)is currently considered a promising anode material due to its exceptionally high capacity for LIBs.However,the significant volumetric changes of SiO_(x)during cycling and its initial Coulombic efficiency(ICE)complicate its use,whether alone or in combination with graphite materials.In this study,a three-dimensional conductive binder network with high electronic conductivity and robust elasticity for graphite/SiO_(x)blended anodes was proposed by chemically anchoring carbon nanotubes and carboxymethyl cellulose binders using tannic acid as a chemical cross-linker.In addition,a dehydrogenation-based prelithiation strategy employing lithium hydride was utilized to enhance the ICE of SiO_(x).The combination of these two strategies increased the CE of SiO_(x)from 74%to87%and effectively mitigated its volume expansion in the graphite/SiO_(x)blended electrode,resulting in an efficient electron-conductive binder network.This led to a remarkable capacity retention of 94%after30 cycles,even under challenging conditions,with a high capacity of 550 mA h g^(-1)and a current density of 4 mA cm^(-2).Furthermore,to validate the feasibility of utilizing prelithiated SiO_(x)anode materials and the conductive binder network in LIBs,a full cell incorporating these materials and a single-crystalline Ni-rich cathode was used.This cell demonstrated a~27.3%increase in discharge capacity of the first cycle(~185.7 mA h g^(-1))and exhibited a cycling stability of 300 cycles.Thus,this study reports a simple,feasible,and insightful method for designing high-performance LIB electrodes.
基金financially supported by the National Key Research and Development Program of China(Grant No.2022YFA1203302)the National Natural Science Foundation of China(Grant Nos.52130209,52188101)+4 种基金the JSPS Kakenhi(Grant Nos.JP25820336,JP20K05281,and JP23H01796)the JST-FOREST Program(Grant No.JPMJFR223T)the WPI-MANA“Challenging Research Program(CRP)”the National Institute for Materials Science(NIMS)“Support system for curiosity-driven research”the“Advanced Research Infrastructure for Materials and Nanotechnology in Japan(ARIM)”of the Ministry of Education,Culture,Sports,Science and Technology(MEXT)(Grant No.JPMXP1223NM5306).
文摘Carbon nanotubes are uniquely featured by the nanoscale tubular structure with a highly-curved surface and defined chirality.The diameter and chirality fundamentally determine their stability and electrical and thermal properties.Up to now,the relationship between the intrinsic thermal conductivity and the atomic features of CNTs has not been established,due to the challenges in precise measurements and characterizations.In this work,we develop a micro electro-thermal device enabling simultaneous thermal measurements by Raman spectroscopy and atomic structural characterization by transmission electron microscopy for individual CNTs.The influence of diameter and chirality is systematically investigated.In addition,the temperature dependence of the thermal conductivity was extracted from parameter optimization of finite-element modeling.It is found that the thermal transport of CNTs depends mainly on the diameter,while the chiral angle has no significant influence.Along with increasing diameter,the room temperature thermal conductivity increases and eventually approaches the limit of flat graphene.
文摘Carbon nanotubes(CNTs)reinforced copper(CNTs/Cu)is one of the most promising and extensively researched materials for replacing traditional Cu-based materials in high-load and high-current applications,particularly within the aerospace industry.Amorphous carbon nanotubes(aCNTs)are a type of carbon nanotubes characterized by the presence of mesopores distributed across their amorphous sidewalls,facilitating connectivity between the hollow core and the external environment.Therefore,we propose utilizing aCNTs as a reinforcing agent for Cu.The mesoporous structure of aCNTs facilitates the interpenetration of Cu into the aCNTs,thereby maintaining the continuity of the matrix properties.Experimental results demonstrate that Cu effectively penetrates the mesoporous sidewalls of aCNTs.Both pure Cu and aCNTs-reinforced Cu exhibit comparable electrical conductivity,while the hardness of the aCNTs/Cu composite is significantly enhanced.Additionally,both the density and porosity of aCNTs/Cu are lower than those of pure Cu,and the introduction of aCNTs helps to reduce the sintering temperature.
基金supported by the Nano&Material Technology Development Program through the National R&D Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(RS-202300260461).
文摘Bipolar plates(BPs)are essential multifunctional components in vanadium redox flow batteries(VRFBs)that require excellent electrical conductivity,low permeability,and strong solid support for the stack.However,conventional BPs are based on graphite sheets,which provide mechanical properties and corrosion resistance but have limitations in terms of electrical conductivity.Although carbon nanotubes(CNTs)have excellent properties,CNT composites with low CNT volume fractions(10–20%)have increased electrolyte permeability and limited electrical conductivity improvement,resulting in low durability and efficiency for VRFBs.This study proposes a novel concept of horizontally aligned CNT nanocomposite bipolar plate(HACN-BP)to address these issues.The HACN-BPs feature an optimized conduction path with a CNT volume fraction of 59%,resulting in reduced manufacturing time while demonstrating superior conductivity and permeability compared to conventional BPs.Furthermore,integrated HACN-BP mitigates ohmic loss that occurs in the BPs,thereby mitigating the potential drop by 40%.Therefore,the utilization of HACN-BP shows superior performance compared to recent studies,a substantial improvement of more than 6%in energy efficiency and 14%in capacity over conventional BP.
基金supported by the National Natural Science Foundation of China(Nos.52170083,51808143)the Science and Technology Innovation Program of Hunan Province(No.2022RC1125)the Hunan Provincial Natural Science Foundation of China(No.2021JJ20007)。
文摘In this study,we present a self-driven photoelectrocatalytic(SD-PEC)system that effectively treats complex uranium-bearing wastewaters for both uranium recovery and organic matter decomposition while generating power.The system utilizes a titanium dioxide nanorod array(TNR)photoelectrode coupled with a silicon solar cell to optimize electron transport,while the cathode is composed of a carbon fiber coated with carboxylated carbon nanotubes(CCNT/CF),which efficiently reduce UO_(2)^(2+).The results demonstrate significant removal efficiency of uranium(complete removal in 25 min at a rate constant of~0.248 min^(-1)),as well as substantial degradation of organic impurities.Furthermore,the system generates sufficient power output to light an LED lamp and exhibits superior performance under various complex wastewater conditions,including simulated seawater and real uranium tailings wastewater.These findings underscore the potential of the SD-PEC system as a versatile approach for sustainable treatment and energy recovery of radioactive wastewater.The significance of this research extends to global environmental challenges,offering an innovative solution for managing radioactive wastewater while simultaneously contributing to renewable energy generation.
