Transition metal oxides are regarded as promising candidates of anode for next-generation lithium-ion batteries(LIBs)due to their ultrahigh theoretical capacity and low cost,but are restricted by their low conductivit...Transition metal oxides are regarded as promising candidates of anode for next-generation lithium-ion batteries(LIBs)due to their ultrahigh theoretical capacity and low cost,but are restricted by their low conductivity and large volume expansion during Li^(+)intercalation.Herein,we designed and constructed a structurally integrated 3D carbon tube(3D-CT)grid film with Mn_(3)O_(4)nanoparticles(Mn_(3)O_(4)-NPs)and carbon nanotubes(CNTs)filled in the inner cavity of CTs(denoted as Mn_(3)O_(4)-NPs/CNTs@3D-CT)as high-performance free-standing anode for LIBs.The Mn_(3)O_(4)-NPs/CNTs@3D-CT grid with Mn_(3)O_(4)-NPs filled in the inner cavity of 3D-CT not only afford sufficient space to overcome the damage caused by the volume expansion of Mn_(3)O_(4)-NPs during charge and discharge processes,but also achieves highly efficient channels for the fast transport of both electrons and Li+during cycling,thus offering outstanding electrochemical performance(865 mAh g^(-1)at 1 A g^(-1)after 300 cycles)and excellent rate capability(418 mAh g^(-1)at 4 A g^(-1))based on the total mass of electrode.The unique 3D-CT framework structure would open up a new route to the highly stable,high-capacity,and excellent cycle and high-rate performance free-standing electrodes for highperformance Li-ion storage.展开更多
The fabrication of one-dimensional metal/N-doped carbon materials has shown a promising prospect as efficient electrocata-lysts for oxygen reduction reaction(ORR).Herein,CoNi alloy nanoparticles anchored on N-doped ca...The fabrication of one-dimensional metal/N-doped carbon materials has shown a promising prospect as efficient electrocata-lysts for oxygen reduction reaction(ORR).Herein,CoNi alloy nanoparticles anchored on N-doped carbon nanotubes(CoNi@NCNT)are prepared by a dual-template strategy,using polypyrrole(PPy)tubes and CoNi-based metal-organic framework as the precursors.The as-formed CoNi@NCNT catalyst displays a half-wave potential(0.83 V)as well as good durability under alkaline medium.The excellent electrocatalytic performance is ascribed to a synergistic coupling of hierarchically tubular structure,highly electronic conductivity,and abundantly alloy-type active sites.When the CoNi@NCNT catalyst is applied in zinc-air battery(ZAB),the device displays a stable charge-discharge cycling performance.The present work affords a useful approach to constructing alloy/nitrogen-incorporated carbon-aceous materials as bifunctional electrocatalysts for high-performance ZABs.展开更多
Sandwich structures have been widely applied in the wing and the horizontal tail of the aircraft,so face sheets of such structure might occur wrinkling deformation in the process of service,which will largely decrease...Sandwich structures have been widely applied in the wing and the horizontal tail of the aircraft,so face sheets of such structure might occur wrinkling deformation in the process of service,which will largely decrease capability of sustaining loads.As a result,this paper aims at proposing a reasonable strategy resisting wrinkling deformation of sandwich structures.To this end,an enhanced higher-order model has been proposed for wrinkling analysis of sandwich structures.Buckling behaviors of a five-layer sandwich plate are firstly analyzed,which is utilized to assess performance of the proposed model.Subsequently,wrinkling behaviors of four sandwich plates are further investigated by utilizing present model,which have been evaluated by using quasi threedimensional(3D)elasticity solutions,3D Finite Element Method(3D-FEM)results and experimental datum.Finally,the present model is utilized to study the buckling and the wrinkling behaviors of sandwich plates reinforced by Carbon Nano Tubes(CNTs).In addition,influence of distribution profile of CNTs on wrinkling behaviors has been analyzed,and a typical distribution profile of CNTs has been chosen to resist wrinkling deformation.Without increase of additional weight,the present strategy can effectively resist wrinkling deformation of sandwich plates,which is rarely reported in published literature.展开更多
Silicon-based(Si-based)materials with high specific capacity are driving the electric vehicle industry and the power storage market.However,poor electrical conductivity and volume expansion during cycling limit its fu...Silicon-based(Si-based)materials with high specific capacity are driving the electric vehicle industry and the power storage market.However,poor electrical conductivity and volume expansion during cycling limit its further application.Rational structural designs and specific material selections can be used to create robust volume buffer structures and conductive networks,which consequently contribute to the electrochemical performance of Si materials.Herein,Si particles were encapsulated in the hollow tubular carbon fiber(HT).Further,the porous carbon layer and SnS_(2)nanosheets were hierarchically assembled on the surface of fibers to create free-standing films with a yolk@multi-shell structure.The unique yolk@multi-shell structure provides sufficient reserved cavities,porous structure,and multiple buffers to significantly resist volume changes.The final electrode is endowed with a multi-dimensional integrated conductive structure by HT and SnS_(2)nanosheets,which greatly improves the poor conductivity of Sibased electrodes.Finally,the free-standing films can be used directly as anodes,achieving a high specific capacity of 1513.6 mAh g^(-1)after 100 cycles at 0.1 A g^(-1).Additionally,the assembled full cell showed 331.4 mAh g^(-1)after 100 cycles at 0.2 A g^(-1),which contributes significantly to the advancement of power electronics technology.展开更多
Transition-metal sulfides(TMSs)with high theoretical capacity and economical suitability are attractive anode materials for potassium-ion batteries(PIBs).However,the inherent low conductivity,tardy K+diffusion kinetic...Transition-metal sulfides(TMSs)with high theoretical capacity and economical suitability are attractive anode materials for potassium-ion batteries(PIBs).However,the inherent low conductivity,tardy K+diffusion kinetics,and huge volume change of TMSs pose a lot of challenges,impeding their practical application in PIBs.Herein,a simple template-assisted vulcanization strategy is presented for impregnating ultrasmall FeS_(2)nanoparticles within flexible carbon nanowires wrapped with robust amorphous carbon tubes(denoted as FeS_(2)-C@CTs),resolving the abovementioned issues and improving the electrochemical performance of PIBs.Specifically,such a crafted FeS_(2)-C@CT-based anode delivers a high reversible capacity of 524 mA h g^(-1)at 50 mA g^(-1),an intriguing rate capability of 208 mA h g^(-1)at 10 A g^(-1),and a decent cycling stability of 167 mA h g^(-1)at 10 A g^(-1)after 1000 cycles.More importantly,a full cell(K_(0.6)CoO_(2)//FeS_(2)-C@CTs)also delivers an enhanced potassium storage performance,showing a high rate capacity of 123 mA h g^(-1)at 1 A g^(-1)and a long cycle life with a capacity retention rate of 87.6%after 200 cycles.展开更多
Bismuth(Bi)is a prospective alloying-type anode material for rechargeable lithium-ion batteries(LIBs)on account of its high theoretical gravimetric capacity.The main challenge faced with Bi-based anode materials,howev...Bismuth(Bi)is a prospective alloying-type anode material for rechargeable lithium-ion batteries(LIBs)on account of its high theoretical gravimetric capacity.The main challenge faced with Bi-based anode materials,however,is the extremely severe volume expansion during charge/discharge,which generally causes severe structural degradation and an unstable solid-electrolyte interphase(SEI).Herein,a nanotube-shaped porous Bi-carbon hybrid is designed and fabricated through a facile template synthesis strategy.Ultrafine Bi nanodots are uniformly embedded and space-confined in nitrogen-doped hollow carbon nanotubes(referred to as Bi@NC),which are constructed employing MnO_(2)nanowires as a template followed by selective etching.The architecture of this unique Bi@NC nanostructure with ample internal voids gives a stable SEI during cycling and accommodates the volume variation of the entrapped Bi,while the ultralong tubular carbon framework with a large aspect ratio can provide continuous longitudinal conductive channels for rapid electron transfer.Benefiting from these features,the as-built Bi@NC composite exhibits superior Li-storage performance,as reflected by the outstanding high rate capability and durable cycling lifespan in LIBs(117 mA h g^(-1)at 10 A g^(-1);470 mA h g^(-1)at 1.0 A g^(-1)after 2000 cycles).The excellent Li-storage property of Bi@NC associated with its structural advantages could provide inspiration for the rational design of other nanostructured alloying-based anode materials toward multifunctional electrochemical energy storage.展开更多
Electric double-layer capacitors(EDLCs)with fast frequency response are regarded as small-scale alternatives to the commercial bulky aluminum electrolytic capacitors.Creating carbon-based nanoarray electrodes with pre...Electric double-layer capacitors(EDLCs)with fast frequency response are regarded as small-scale alternatives to the commercial bulky aluminum electrolytic capacitors.Creating carbon-based nanoarray electrodes with precise alignment and smooth ion channels is crucial for enhancing EDLCs’performance.However,controlling the density of macropore-dominated nanoarray electrodes poses challenges in boosting the capacitance of line-filtering EDLCs.Herein,a simple technique to finely adjust the vertical-pore diameter and inter-spacing in three-dimensional nanoporous anodic aluminum oxide(3D-AAO)template is achieved,and 3D compactly arranged carbon tube(3D-CACT)nanoarrays are created as electrodes for symmetrical EDLCs using nanoporous 3D-AAO template-assisted chemical vapor deposition of carbon.The 3D-CACT electrodes demonstrate a high surface area of 253.0 m^(2) g^(−1),a D/G band intensity ratio of 0.94,and a C/O atomic ratio of 8.As a result,the high-density 3D-CT nanoarray-based sandwich-type EDLCs demonstrate a record high specific areal capacitance of 3.23 mF cm^(-2) at 120 Hz and exceptional fast frequency response due to the vertically aligned and highly ordered nanoarray of closely packed CT units.The 3D-CT nanoarray electrode-based EDLCs could serve as line filters in integrated circuits,aiding power system miniaturization.展开更多
The stowing and deploying experiment was conducted for three 700 mm long thin-walled tubes,and the structural behavior characteristics parameters were measured clearly,including strain,deformation and wrapping moment....The stowing and deploying experiment was conducted for three 700 mm long thin-walled tubes,and the structural behavior characteristics parameters were measured clearly,including strain,deformation and wrapping moment.3D finite element models(FEM)were built subsequently and explicit dynamic method was used to simulate the stowing and deploying of the lenticular carbon fiber reinforced polymer(CFRP)thin-walled tubular space boom,which was designed as four-ply(45°/-45°/45°/-45°)lay-up.The stress and energy during the wrapping process were got and compared with different wrapping angular velocity,the reasonable wrapping angular velocity and effective method were conformed,and structural behavior characteristics were obtained.The results were compared and discussed as well,and the results show that the numerical results by 0.628 rad/s velocity agree well with the measured values.In this paper,the numerical procedure and experimental results are valuable to the optimization design of CFRP thin-walled tubular space boom and future research.展开更多
In ground tests of hypersonic scramjet, the highenthalpy airstream produced by burning hydrocarbon fuels often contains contaminants of water vapor and carbon dioxide. The contaminants may change the ignition characte...In ground tests of hypersonic scramjet, the highenthalpy airstream produced by burning hydrocarbon fuels often contains contaminants of water vapor and carbon dioxide. The contaminants may change the ignition characteristics of fuels between ground tests and real flights. In order to properly assess the influence of the contaminants on ignition characteristics of hydrocarbon fuels, the effect of water vapor and carbon dioxide on the ignition delay times of China RP-3 kerosene was studied behind reflected shock waves in a preheated shock tube. Experiments were conducted over a wider temperature range of 800-1 500 K, at a pressure of 0.3 MPa, equivalence ratios of 0.5 and 1, and oxygen concentration of 20%. Ignition delay times were determined from the onset of the excited radical OH emission together with the pressure profile. Ignition delay times were measured for four cases： （1） clean gas, （2） gas vitiated with 10% and 20% water vapor in mole, （3） gas vitiated with 10% carbon dioxide in mole, and （4） gas vitiated with 10% water vapor and 10% carbon dioxide, 20% water vapor and 10% carbon dioxide in mole. The results show that carbon dioxide produces an inhibiting effect at temperatures below 1 300 K when Ф = 0.5, whereas water vapor appears to accelerate the ignition process below a critical temperature of about 1 000 K when Ф = 0.5. When both water vapor and carbon dioxide exist together, a minor inhibiting effect is observed at Ф = 0.5, while no effect is found at Ф = 1.0. The results are also discussed preliminary by considering both the combustion reaction mechanism and the thermophysics properties of the fuel mixtures. The current measurements demonstrate vitiation effects of water vapor and carbon dioxide on the autoignition characteristics of China RP-3 kerosene at air-like O2 concentration. It is important to account for such effects when data are extrapolated from ground testing to real flight conditions.展开更多
Amidst <span style="font-family:;" "="">the <span style="font-family:;" "="">COVID-19 pandemic, environmental problems such as energy crisis, global warmin...Amidst <span style="font-family:;" "="">the <span style="font-family:;" "="">COVID-19 pandemic, environmental problems such as energy crisis, global warming, and contamination from pathogenic micro-organisms are still prevailed and strongly demanded progress in high<span style="font-family:;" "="">-<span style="font-family:;" "="">performance<span style="font-family:;" "=""> energy storing and anti-microbial materials. The nanocomposites are materials that have earned large interest owing to their promising applications for countering global issues related to sustainable energy and<span style="font-family:;" "=""> a<span style="font-family:;" "=""> flourishing environment. Here, polypyrrole <span style="font-family:;" "="">coated<span style="font-family:;" "=""> hybrid nanocomposites of multi-walled<span style="font-family:;" "=""> carbon nanotube and cadmium sulfide quantum dots named MCP were synthesized using facile and low-cost in-situ oxidative polymerization method. Characterization techniques confirmed the synthesis. Electrochemical studies showed that the nanocomposite 1-MCP showed an impressively higher super capacitance behavior in comparison to f-MWCNT, 7-MCP and 5-MCP. The improved performance of the nanocomposites was attributed mainly to the good conductivity of carbon nanotubes and polypyrrole, high surface area, and stability of the carbon nanotubes and the high electrocatalytic activity of the cadmium sulfide quantum dots. Owing to the synergistic effect of MWCNT, CdS, and PPy the synthesized ternary nanocomposite also inhibited the growth and multiplication of tested bacteria such as S. aureus, and E. coli completely within 24 h. On the whole, the assimilated nanocomposite MCP opens promising aspects for the development of upcoming energy storage devices and as<span style="color:red;"> <span style="font-family:;" "="">an <span style="font-family:;" "="">antibacterial agent.展开更多
Extremely fast-charging and longlife span are critical yet challenging for the development of cost-effective and sustainable potassium-ion batteries(PIBs)due to the sluggish kinetics and rapid capacity decay of graphi...Extremely fast-charging and longlife span are critical yet challenging for the development of cost-effective and sustainable potassium-ion batteries(PIBs)due to the sluggish kinetics and rapid capacity decay of graphite anodes caused by the large radius of K ions(1.38 A).To tackle this issue,here a new type of nitrogen-doped graphitic carbon tubes(NGCTs)is reported via a ZrO_(2)-templated chemical vapor deposition(CVD)approach.The carbon interlayer spacing,crystallite size,and Nconfigurations in NGCTs are controlled by adjusting the CVD temperature(800,900,and 1000℃).The optimized NGCT-900 sample well balances the graphitic domains and structural defects,thus enabling fast K^(+)insertion/extraction below 1 V(vs.K^(+)/K).These tubular carbon membranes achieve exceptional K^(+)-storage performance including high K^(+)-storage capacities of 404 mAh·g^(-1)at 0.1 A·g^(-1),ultrafast charging at 50 A·g^(-1)and a super-long cycle life of up to 6000 cycles.Ex-situ X-ray diffraction(XRD),insitu Raman,and galvanostatic intermittent titration technique(GITT)analyses reveal a synergistic K^(+)-adsorptionintercalation mechanism.Further comparison with S or P heteroatoms underscores the significance of N-doping in enhancing reversible K^(+)intercalation into graphitic domains and boosting surface adsorption capacity.The fabricated NGCT-900//K_(x)Ni_(0.33)Mn_(0.67)O_(2)PIB(1.2-3.2 V)provides both a high-energy density of 187 Wh·kg^(-1)(comparable to graphite//LiFePO_(4)lithium-ion batteries(LIBs))and a high-power density of 2200 W·kg^(-1)at 123 Wh·kg^(-1).This study establishes a carbon anode design strategy for advanced potassium storage.展开更多
Herein,nitrogen and sulfur co-doped carbon nanotubes(NS-CNT)adsorbents were synthesized via the chemical vapor deposition technique at 1000°C by employing the camphor,urea and sulfur trioxide pyridine.In this stu...Herein,nitrogen and sulfur co-doped carbon nanotubes(NS-CNT)adsorbents were synthesized via the chemical vapor deposition technique at 1000°C by employing the camphor,urea and sulfur trioxide pyridine.In this study,desulfurization of two types of mercaptans(dibenzothiophene(DBT)and tertiary butyl mercaptan(TBM)as nonlinear and linear forms of mercaptan)was studied.In this regard,a maximum capacity of NS-CNT was obtained as 106.9 and 79.4 mg/g and also the removal efficiencies of 98.6%and 88.3%were achieved after 4 h at 298K and 0.9 g of NS-CNT for DBT and TBM,respectively.Characterization of the NS-CNTs was carried out through exploiting scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and elemental analysis(CHN).The isotherm equilibrium data could be ascribed to the Freundlich nonlinear regression form and the kinetic data was fitted by nonlinear form of the pseudo second order model.The negative values of ΔS^(0),ΔH^(0) and ΔG^(0) specify that the adsorption of both types of mercaptans was a natural exothermic process with a reduced entropy.Maintenance of more than 96%of the adsorption capacity even after nine cycles suggest the NS-CNT as a superior adsorbent for mercaptans removal in the industry.Density functional theory(DFT)calculations were also performed to peruse the effects of S/N co-doping and carbon monovacancy defects in CNTs toward the adsorption of DBT and TBM.展开更多
Titania coating of multi wall carbon nano tube(MWCNT) was carried out by sol-gel method in order to improve its photo catalytic properties.The effect of MWCNT/TiO_2 mass to volume ratio on adsorption ability,reaction ...Titania coating of multi wall carbon nano tube(MWCNT) was carried out by sol-gel method in order to improve its photo catalytic properties.The effect of MWCNT/TiO_2 mass to volume ratio on adsorption ability,reaction rate and photo-catalytic removal efficiency of dibenzothiophene(DBT) from n-hexane solution was investigated using a 9 W UV lamp.The results show that the addition of nanotubes improves the photo-catalytic properties of TiO_2 by two factors;however,the DBT removal rate versus MWCNT content is found to follow a bimodal pattern.Two factors are observed to affect the removal rate of DBT and produce two optimum values for MWCNT content.First,large quantities of MWCNTs prevent light absorption by the solution and decrease removal efficiency.By contrast,a low dosage of MWCNT causes recombination of the electron holes,which also decreases the DBT removal rate.The optimum MWCNT contents in the composite are found to be 0.25 g and 0.75 g MWCNT per 80 m L of sol.展开更多
A possible way to increase thermal conductivity of working fluids, while keeping pressure drop at acceptable levels, is through nanofluids. Nanofluids are nano-sized particles dispersed in conventional working fluids....A possible way to increase thermal conductivity of working fluids, while keeping pressure drop at acceptable levels, is through nanofluids. Nanofluids are nano-sized particles dispersed in conventional working fluids. A great number of materials have potential to be used in nanoparticles production and then in nanofluids;one of them is Multi-Walled Carbon Nano Tubes (MWCNT). They have thermal conductivity around 3000 W/mK while other materials used as nanoparticles like CuO have thermal conductivity of 76.5 W/mK. Due to this fact, MWCNT nanoparticles have potential to be used in nanofluids production, aiming to increase heat transfer rate in energy systems. In this context, the main goal of this paper is to evaluate from the synthesis to the experimental measurement of thermal conductivity of nanofluid samples based on functionalized (-OH) MWCNT nanoparticles. They will be analyzed nanoparticles with different functionalization degrees (4% wt, 6% wt, and 9% wt). In addition, it will be quantified other thermophysical properties (dynamic viscosity, specific heat and specific mass) of the synthetized nanofluids. So, the present work can contribute with experimental data that will help researches in the study and development of MWCNT nanofluids. According to the results, the maximum increment obtained in thermal conductivity was 10.65% in relation to the base fluid (water).展开更多
Because of its merits,acrylic resin was chosen to improve the mechanical,conductive and hydrophobic properties.Carbon fiber powders (CF),carbon nanotubes (MWCNT),and nano-TiO_(2) were incorporated into the acrylic res...Because of its merits,acrylic resin was chosen to improve the mechanical,conductive and hydrophobic properties.Carbon fiber powders (CF),carbon nanotubes (MWCNT),and nano-TiO_(2) were incorporated into the acrylic resin to prepare the corona-proof conductive composite coatings.The incorporation of CF and MWCNT may improve the conductivity and mechanical strength of the coatings.However,the addition of nano-TiO_(2) may increase the hydrophobicity of the coatings.Thus,the effects of different additives on the mechanical properties,conductivity,hydrophobicity and heat resistance of the conductive film were studied.The experimental results show that the incorporation of carbon fiber powders and multi walled carbon nanotubes can significantly improve both the conductivity and mechanical properties of the conductive coatings,and the addition of nano titanium dioxide can improve the hydrophobicity of the conductive film.展开更多
The rapid development of sustainable green energy,which often generates fluctuating electrical signals,has driven the demand for high-performance filter capacitors in alternating/direct current conversion.Replacing bu...The rapid development of sustainable green energy,which often generates fluctuating electrical signals,has driven the demand for high-performance filter capacitors in alternating/direct current conversion.Replacing bulky aluminum electrolytic capacitors with electric double-layer capacitors(EDLCs)holds promise for electronics miniaturization.However,EDLCs face a trade-off between charge storage ability and ion/electron transport speed.Here,we demonstrate three-dimensional Y-branched carbon tube(3D-YCT)grids with a hierarchically porous structure as electrodes for line-filtering EDLCs.The branching patterns and positions within the 3D-YCT are precisely tailored through the nanochannels inside anodic aluminum oxide templates.These integrated 3D Y-branched CT arrays provide unobstructed pathways for fast frequency response and extensive surfaces for high capacitance.The resulting 3D-YCT-based EDLC achieves a desirable specific areal capacitance(C_(A))of 3.6 mF cm^(-2)with a phase angle of-80°at 120 Hz,outperforming most reported line-filtering EDLCs and demonstrating excellent line-filtering performance.These findings offer valuable insights for constructing miniaturized filter capacitors.展开更多
Exploring superior electrocatalyst for hydrogen evolution reaction(HER)is an urgent need for hydrogen production based on water splitting.The redistribution of electrons and the increase of active sites through multi-...Exploring superior electrocatalyst for hydrogen evolution reaction(HER)is an urgent need for hydrogen production based on water splitting.The redistribution of electrons and the increase of active sites through multi-interface designing of electrocatalyst are powerful strategies to improve the catalytic efficiency.Herein,a three-phase interface structure of N,P co-doped carbon tube embedded with MoO_(2)/Mo_(2)C(MoO_(2)/Mo_(2)C-CT)was fabricated via a cooperative polymerizing-embedding and pyrolysis strategy.Work function and X-ray photoelectron spectroscopy(XPS)verified that the interfacial charge was quantificationally modulated,achieving an intrinsically enhanced charge transfer by an induced built-in electric field.Theoretical study of density functional theory(DFT)illustrated that triple-interface structure showed a lower energy for H*+H2O*than that of single-interface counterparts.The triple-interface MoO_(2)/Mo_(2)C-CT delivered a lower overpotential of 129 mV at 10 mA·cm^(−2)than that of either single-interface MoO_(2)-CT or Mo_(2)C-CT catalyst.This work may put forward an attractive approach for modulating electronic structure and provide insights into the understanding of triple-interface structure towards HER.展开更多
The rational design of electrodes is the key to achieving ultrahigh-power performance in electrochemical energy storage devices.Recently,we have constructed well-organized and integrated three-dimensional(3D)carbon tu...The rational design of electrodes is the key to achieving ultrahigh-power performance in electrochemical energy storage devices.Recently,we have constructed well-organized and integrated three-dimensional(3D)carbon tube(CT)grids(3D-CTGs)using a 3D porous anodic aluminum oxide template-assisted method as electrodes of electrical double-layer capacitors(EDLCs),showing excellent frequency response performance.The unique design warrants fast ion migration channels,excellent electronic conductivity,and good structural stability.This study achieved one of the highest carbon-based ultrahigh-power EDLCs with the 3D-CTG electrodes,resulting in ultrahigh power of 437 and 1708 W·cm−3 with aqueous and organic electrolytes,respectively.Capacitors constructed with these electrodes would have important application prospects in the ultrahigh-power output.The rational design and fabrication of the 3D-CTGs electrodes have demonstrated their capability to build capacitors with ultrahighpower performance and open up new possibilities for applications requiring high-power output.展开更多
Rechargeable Zn-air batteries(ZABs)have received extensive attention,while their real applications are highly restricted by the slow kinetics of the oxygen reduction and oxygen evolution reactions(ORR/OER).Herein,we r...Rechargeable Zn-air batteries(ZABs)have received extensive attention,while their real applications are highly restricted by the slow kinetics of the oxygen reduction and oxygen evolution reactions(ORR/OER).Herein,we report a“bridge”structured flexible self-supporting bifunctional oxygen electrode(CNT@Co-CNFF50-900)with strong active and stable Co-N/C@pyridine N/C@CNTs reaction centers.Benefiting from the electron distribution optimization and the advantages of hierarchical catalytic design,the CNT@Co-CNF_(F50-900)electrode had superior ORR/OER activity with a small potential gap(ΔE)of 0.74 V.Reinforced by highly graphitized carbon and the“π-π”bond,the free-standing CNT@Co-CNFF50-900 electrode exhibited outstanding catalytic stability with only 36 mV attenuation.Impressively,the CNT@Co-CNFF50-900-based liquid ZAB showed a high power density of 371 mW cm^(−2),a high energy density of 894 Wh kg^(−1),and a long cycling life of over 130 h.The assembled quasi-solid-state ZAB also demonstrated a high power density,attaining 81 mW cm^(−2),with excellent charge-discharge durability beyond 100 h and extremely high flexibility under the multi-angle application.This study provides an effective electrospinning solution for integrating high-efficiency electrocatalysts and electrodes for energy storage and conversion devices.展开更多
基金supported by the Natural Science Foundation of China(91963202 and 52072372)the Key Research Program of Frontier Sciences(CAS,Grant,QYZDJ-SSW-SLH046)the CAS/SAFEA International Partnership Program for Creative Research Teams,and the Hefei Institutes of Physical Science,Chinese Academy of Sciences Director’s Fund(YZJ ZX202018)
文摘Transition metal oxides are regarded as promising candidates of anode for next-generation lithium-ion batteries(LIBs)due to their ultrahigh theoretical capacity and low cost,but are restricted by their low conductivity and large volume expansion during Li^(+)intercalation.Herein,we designed and constructed a structurally integrated 3D carbon tube(3D-CT)grid film with Mn_(3)O_(4)nanoparticles(Mn_(3)O_(4)-NPs)and carbon nanotubes(CNTs)filled in the inner cavity of CTs(denoted as Mn_(3)O_(4)-NPs/CNTs@3D-CT)as high-performance free-standing anode for LIBs.The Mn_(3)O_(4)-NPs/CNTs@3D-CT grid with Mn_(3)O_(4)-NPs filled in the inner cavity of 3D-CT not only afford sufficient space to overcome the damage caused by the volume expansion of Mn_(3)O_(4)-NPs during charge and discharge processes,but also achieves highly efficient channels for the fast transport of both electrons and Li+during cycling,thus offering outstanding electrochemical performance(865 mAh g^(-1)at 1 A g^(-1)after 300 cycles)and excellent rate capability(418 mAh g^(-1)at 4 A g^(-1))based on the total mass of electrode.The unique 3D-CT framework structure would open up a new route to the highly stable,high-capacity,and excellent cycle and high-rate performance free-standing electrodes for highperformance Li-ion storage.
基金support by the National Natural Science Foundation of China(No.22279047).
文摘The fabrication of one-dimensional metal/N-doped carbon materials has shown a promising prospect as efficient electrocata-lysts for oxygen reduction reaction(ORR).Herein,CoNi alloy nanoparticles anchored on N-doped carbon nanotubes(CoNi@NCNT)are prepared by a dual-template strategy,using polypyrrole(PPy)tubes and CoNi-based metal-organic framework as the precursors.The as-formed CoNi@NCNT catalyst displays a half-wave potential(0.83 V)as well as good durability under alkaline medium.The excellent electrocatalytic performance is ascribed to a synergistic coupling of hierarchically tubular structure,highly electronic conductivity,and abundantly alloy-type active sites.When the CoNi@NCNT catalyst is applied in zinc-air battery(ZAB),the device displays a stable charge-discharge cycling performance.The present work affords a useful approach to constructing alloy/nitrogen-incorporated carbon-aceous materials as bifunctional electrocatalysts for high-performance ZABs.
基金supported by the National Natural Sciences Foundation of China(No.12172295)SKLLIM1902,China.
文摘Sandwich structures have been widely applied in the wing and the horizontal tail of the aircraft,so face sheets of such structure might occur wrinkling deformation in the process of service,which will largely decrease capability of sustaining loads.As a result,this paper aims at proposing a reasonable strategy resisting wrinkling deformation of sandwich structures.To this end,an enhanced higher-order model has been proposed for wrinkling analysis of sandwich structures.Buckling behaviors of a five-layer sandwich plate are firstly analyzed,which is utilized to assess performance of the proposed model.Subsequently,wrinkling behaviors of four sandwich plates are further investigated by utilizing present model,which have been evaluated by using quasi threedimensional(3D)elasticity solutions,3D Finite Element Method(3D-FEM)results and experimental datum.Finally,the present model is utilized to study the buckling and the wrinkling behaviors of sandwich plates reinforced by Carbon Nano Tubes(CNTs).In addition,influence of distribution profile of CNTs on wrinkling behaviors has been analyzed,and a typical distribution profile of CNTs has been chosen to resist wrinkling deformation.Without increase of additional weight,the present strategy can effectively resist wrinkling deformation of sandwich plates,which is rarely reported in published literature.
基金supported by the Shanghai Aerospace Science and Technology Innovation Fundation(No.SAST2020105)the Natural Science Basic Research Program of Shaanxi Province(No.2024JC-YBQN-0442)+1 种基金We would also like to acknowledge Analytical&Testing Center of Northwestern Polytechnical University for the Equipment Support Provided for FETEM(FEI Talos F200X)SEM(FEI Verios G4).
文摘Silicon-based(Si-based)materials with high specific capacity are driving the electric vehicle industry and the power storage market.However,poor electrical conductivity and volume expansion during cycling limit its further application.Rational structural designs and specific material selections can be used to create robust volume buffer structures and conductive networks,which consequently contribute to the electrochemical performance of Si materials.Herein,Si particles were encapsulated in the hollow tubular carbon fiber(HT).Further,the porous carbon layer and SnS_(2)nanosheets were hierarchically assembled on the surface of fibers to create free-standing films with a yolk@multi-shell structure.The unique yolk@multi-shell structure provides sufficient reserved cavities,porous structure,and multiple buffers to significantly resist volume changes.The final electrode is endowed with a multi-dimensional integrated conductive structure by HT and SnS_(2)nanosheets,which greatly improves the poor conductivity of Sibased electrodes.Finally,the free-standing films can be used directly as anodes,achieving a high specific capacity of 1513.6 mAh g^(-1)after 100 cycles at 0.1 A g^(-1).Additionally,the assembled full cell showed 331.4 mAh g^(-1)after 100 cycles at 0.2 A g^(-1),which contributes significantly to the advancement of power electronics technology.
基金financially supported by the National Natural Science Foundation of China(No.51672071,51802085,51772296 and 51902090)the“111”Project(D17007)+2 种基金the National Students’Platform for Innovation and Entrepreneurship Training Program(No.201910476010)the China Postdoctoral Science Foundation(Grant No.2019 M652546)the Henan Province Postdoctoral Start-Up Foundation(Grant no.1901017).
文摘Transition-metal sulfides(TMSs)with high theoretical capacity and economical suitability are attractive anode materials for potassium-ion batteries(PIBs).However,the inherent low conductivity,tardy K+diffusion kinetics,and huge volume change of TMSs pose a lot of challenges,impeding their practical application in PIBs.Herein,a simple template-assisted vulcanization strategy is presented for impregnating ultrasmall FeS_(2)nanoparticles within flexible carbon nanowires wrapped with robust amorphous carbon tubes(denoted as FeS_(2)-C@CTs),resolving the abovementioned issues and improving the electrochemical performance of PIBs.Specifically,such a crafted FeS_(2)-C@CT-based anode delivers a high reversible capacity of 524 mA h g^(-1)at 50 mA g^(-1),an intriguing rate capability of 208 mA h g^(-1)at 10 A g^(-1),and a decent cycling stability of 167 mA h g^(-1)at 10 A g^(-1)after 1000 cycles.More importantly,a full cell(K_(0.6)CoO_(2)//FeS_(2)-C@CTs)also delivers an enhanced potassium storage performance,showing a high rate capacity of 123 mA h g^(-1)at 1 A g^(-1)and a long cycle life with a capacity retention rate of 87.6%after 200 cycles.
基金Fundamental Research Funds for the Central Universities(2016SCU04A18)College Students’Innovative Entrepreneurial Training Plan Program(No.201910610316)Graduate Students’Research and Innovation Fund of Sichuan University(No.2018YJSY070)。
文摘Bismuth(Bi)is a prospective alloying-type anode material for rechargeable lithium-ion batteries(LIBs)on account of its high theoretical gravimetric capacity.The main challenge faced with Bi-based anode materials,however,is the extremely severe volume expansion during charge/discharge,which generally causes severe structural degradation and an unstable solid-electrolyte interphase(SEI).Herein,a nanotube-shaped porous Bi-carbon hybrid is designed and fabricated through a facile template synthesis strategy.Ultrafine Bi nanodots are uniformly embedded and space-confined in nitrogen-doped hollow carbon nanotubes(referred to as Bi@NC),which are constructed employing MnO_(2)nanowires as a template followed by selective etching.The architecture of this unique Bi@NC nanostructure with ample internal voids gives a stable SEI during cycling and accommodates the volume variation of the entrapped Bi,while the ultralong tubular carbon framework with a large aspect ratio can provide continuous longitudinal conductive channels for rapid electron transfer.Benefiting from these features,the as-built Bi@NC composite exhibits superior Li-storage performance,as reflected by the outstanding high rate capability and durable cycling lifespan in LIBs(117 mA h g^(-1)at 10 A g^(-1);470 mA h g^(-1)at 1.0 A g^(-1)after 2000 cycles).The excellent Li-storage property of Bi@NC associated with its structural advantages could provide inspiration for the rational design of other nanostructured alloying-based anode materials toward multifunctional electrochemical energy storage.
基金supported by the National Natural Science Foundation of China(91963202,52072372,52372241,52232007,12325203)HFIPS Director’s Fund(BJPY2023A07,YZJJ-GGZX-2022-01).
文摘Electric double-layer capacitors(EDLCs)with fast frequency response are regarded as small-scale alternatives to the commercial bulky aluminum electrolytic capacitors.Creating carbon-based nanoarray electrodes with precise alignment and smooth ion channels is crucial for enhancing EDLCs’performance.However,controlling the density of macropore-dominated nanoarray electrodes poses challenges in boosting the capacitance of line-filtering EDLCs.Herein,a simple technique to finely adjust the vertical-pore diameter and inter-spacing in three-dimensional nanoporous anodic aluminum oxide(3D-AAO)template is achieved,and 3D compactly arranged carbon tube(3D-CACT)nanoarrays are created as electrodes for symmetrical EDLCs using nanoporous 3D-AAO template-assisted chemical vapor deposition of carbon.The 3D-CACT electrodes demonstrate a high surface area of 253.0 m^(2) g^(−1),a D/G band intensity ratio of 0.94,and a C/O atomic ratio of 8.As a result,the high-density 3D-CT nanoarray-based sandwich-type EDLCs demonstrate a record high specific areal capacitance of 3.23 mF cm^(-2) at 120 Hz and exceptional fast frequency response due to the vertically aligned and highly ordered nanoarray of closely packed CT units.The 3D-CT nanoarray electrode-based EDLCs could serve as line filters in integrated circuits,aiding power system miniaturization.
基金the National Natural Science Foundation of China(No.50878128)the Shanghai Aerospace Foundation(No.HTJ10-15)
文摘The stowing and deploying experiment was conducted for three 700 mm long thin-walled tubes,and the structural behavior characteristics parameters were measured clearly,including strain,deformation and wrapping moment.3D finite element models(FEM)were built subsequently and explicit dynamic method was used to simulate the stowing and deploying of the lenticular carbon fiber reinforced polymer(CFRP)thin-walled tubular space boom,which was designed as four-ply(45°/-45°/45°/-45°)lay-up.The stress and energy during the wrapping process were got and compared with different wrapping angular velocity,the reasonable wrapping angular velocity and effective method were conformed,and structural behavior characteristics were obtained.The results were compared and discussed as well,and the results show that the numerical results by 0.628 rad/s velocity agree well with the measured values.In this paper,the numerical procedure and experimental results are valuable to the optimization design of CFRP thin-walled tubular space boom and future research.
基金supported by the National Natural Science Foundation of China(90916017)
文摘In ground tests of hypersonic scramjet, the highenthalpy airstream produced by burning hydrocarbon fuels often contains contaminants of water vapor and carbon dioxide. The contaminants may change the ignition characteristics of fuels between ground tests and real flights. In order to properly assess the influence of the contaminants on ignition characteristics of hydrocarbon fuels, the effect of water vapor and carbon dioxide on the ignition delay times of China RP-3 kerosene was studied behind reflected shock waves in a preheated shock tube. Experiments were conducted over a wider temperature range of 800-1 500 K, at a pressure of 0.3 MPa, equivalence ratios of 0.5 and 1, and oxygen concentration of 20%. Ignition delay times were determined from the onset of the excited radical OH emission together with the pressure profile. Ignition delay times were measured for four cases： （1） clean gas, （2） gas vitiated with 10% and 20% water vapor in mole, （3） gas vitiated with 10% carbon dioxide in mole, and （4） gas vitiated with 10% water vapor and 10% carbon dioxide, 20% water vapor and 10% carbon dioxide in mole. The results show that carbon dioxide produces an inhibiting effect at temperatures below 1 300 K when Ф = 0.5, whereas water vapor appears to accelerate the ignition process below a critical temperature of about 1 000 K when Ф = 0.5. When both water vapor and carbon dioxide exist together, a minor inhibiting effect is observed at Ф = 0.5, while no effect is found at Ф = 1.0. The results are also discussed preliminary by considering both the combustion reaction mechanism and the thermophysics properties of the fuel mixtures. The current measurements demonstrate vitiation effects of water vapor and carbon dioxide on the autoignition characteristics of China RP-3 kerosene at air-like O2 concentration. It is important to account for such effects when data are extrapolated from ground testing to real flight conditions.
文摘Amidst <span style="font-family:;" "="">the <span style="font-family:;" "="">COVID-19 pandemic, environmental problems such as energy crisis, global warming, and contamination from pathogenic micro-organisms are still prevailed and strongly demanded progress in high<span style="font-family:;" "="">-<span style="font-family:;" "="">performance<span style="font-family:;" "=""> energy storing and anti-microbial materials. The nanocomposites are materials that have earned large interest owing to their promising applications for countering global issues related to sustainable energy and<span style="font-family:;" "=""> a<span style="font-family:;" "=""> flourishing environment. Here, polypyrrole <span style="font-family:;" "="">coated<span style="font-family:;" "=""> hybrid nanocomposites of multi-walled<span style="font-family:;" "=""> carbon nanotube and cadmium sulfide quantum dots named MCP were synthesized using facile and low-cost in-situ oxidative polymerization method. Characterization techniques confirmed the synthesis. Electrochemical studies showed that the nanocomposite 1-MCP showed an impressively higher super capacitance behavior in comparison to f-MWCNT, 7-MCP and 5-MCP. The improved performance of the nanocomposites was attributed mainly to the good conductivity of carbon nanotubes and polypyrrole, high surface area, and stability of the carbon nanotubes and the high electrocatalytic activity of the cadmium sulfide quantum dots. Owing to the synergistic effect of MWCNT, CdS, and PPy the synthesized ternary nanocomposite also inhibited the growth and multiplication of tested bacteria such as S. aureus, and E. coli completely within 24 h. On the whole, the assimilated nanocomposite MCP opens promising aspects for the development of upcoming energy storage devices and as<span style="color:red;"> <span style="font-family:;" "="">an <span style="font-family:;" "="">antibacterial agent.
基金financially supported by the National Natural Science Foundation of China(Nos.22579153 and 22279122)Shenzhen Science and Technology Program(No.JCYJ20220530162402005)Wuhan Key Research and Development Program(No.2025060102030012).
文摘Extremely fast-charging and longlife span are critical yet challenging for the development of cost-effective and sustainable potassium-ion batteries(PIBs)due to the sluggish kinetics and rapid capacity decay of graphite anodes caused by the large radius of K ions(1.38 A).To tackle this issue,here a new type of nitrogen-doped graphitic carbon tubes(NGCTs)is reported via a ZrO_(2)-templated chemical vapor deposition(CVD)approach.The carbon interlayer spacing,crystallite size,and Nconfigurations in NGCTs are controlled by adjusting the CVD temperature(800,900,and 1000℃).The optimized NGCT-900 sample well balances the graphitic domains and structural defects,thus enabling fast K^(+)insertion/extraction below 1 V(vs.K^(+)/K).These tubular carbon membranes achieve exceptional K^(+)-storage performance including high K^(+)-storage capacities of 404 mAh·g^(-1)at 0.1 A·g^(-1),ultrafast charging at 50 A·g^(-1)and a super-long cycle life of up to 6000 cycles.Ex-situ X-ray diffraction(XRD),insitu Raman,and galvanostatic intermittent titration technique(GITT)analyses reveal a synergistic K^(+)-adsorptionintercalation mechanism.Further comparison with S or P heteroatoms underscores the significance of N-doping in enhancing reversible K^(+)intercalation into graphitic domains and boosting surface adsorption capacity.The fabricated NGCT-900//K_(x)Ni_(0.33)Mn_(0.67)O_(2)PIB(1.2-3.2 V)provides both a high-energy density of 187 Wh·kg^(-1)(comparable to graphite//LiFePO_(4)lithium-ion batteries(LIBs))and a high-power density of 2200 W·kg^(-1)at 123 Wh·kg^(-1).This study establishes a carbon anode design strategy for advanced potassium storage.
文摘Herein,nitrogen and sulfur co-doped carbon nanotubes(NS-CNT)adsorbents were synthesized via the chemical vapor deposition technique at 1000°C by employing the camphor,urea and sulfur trioxide pyridine.In this study,desulfurization of two types of mercaptans(dibenzothiophene(DBT)and tertiary butyl mercaptan(TBM)as nonlinear and linear forms of mercaptan)was studied.In this regard,a maximum capacity of NS-CNT was obtained as 106.9 and 79.4 mg/g and also the removal efficiencies of 98.6%and 88.3%were achieved after 4 h at 298K and 0.9 g of NS-CNT for DBT and TBM,respectively.Characterization of the NS-CNTs was carried out through exploiting scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and elemental analysis(CHN).The isotherm equilibrium data could be ascribed to the Freundlich nonlinear regression form and the kinetic data was fitted by nonlinear form of the pseudo second order model.The negative values of ΔS^(0),ΔH^(0) and ΔG^(0) specify that the adsorption of both types of mercaptans was a natural exothermic process with a reduced entropy.Maintenance of more than 96%of the adsorption capacity even after nine cycles suggest the NS-CNT as a superior adsorbent for mercaptans removal in the industry.Density functional theory(DFT)calculations were also performed to peruse the effects of S/N co-doping and carbon monovacancy defects in CNTs toward the adsorption of DBT and TBM.
文摘Titania coating of multi wall carbon nano tube(MWCNT) was carried out by sol-gel method in order to improve its photo catalytic properties.The effect of MWCNT/TiO_2 mass to volume ratio on adsorption ability,reaction rate and photo-catalytic removal efficiency of dibenzothiophene(DBT) from n-hexane solution was investigated using a 9 W UV lamp.The results show that the addition of nanotubes improves the photo-catalytic properties of TiO_2 by two factors;however,the DBT removal rate versus MWCNT content is found to follow a bimodal pattern.Two factors are observed to affect the removal rate of DBT and produce two optimum values for MWCNT content.First,large quantities of MWCNTs prevent light absorption by the solution and decrease removal efficiency.By contrast,a low dosage of MWCNT causes recombination of the electron holes,which also decreases the DBT removal rate.The optimum MWCNT contents in the composite are found to be 0.25 g and 0.75 g MWCNT per 80 m L of sol.
文摘A possible way to increase thermal conductivity of working fluids, while keeping pressure drop at acceptable levels, is through nanofluids. Nanofluids are nano-sized particles dispersed in conventional working fluids. A great number of materials have potential to be used in nanoparticles production and then in nanofluids;one of them is Multi-Walled Carbon Nano Tubes (MWCNT). They have thermal conductivity around 3000 W/mK while other materials used as nanoparticles like CuO have thermal conductivity of 76.5 W/mK. Due to this fact, MWCNT nanoparticles have potential to be used in nanofluids production, aiming to increase heat transfer rate in energy systems. In this context, the main goal of this paper is to evaluate from the synthesis to the experimental measurement of thermal conductivity of nanofluid samples based on functionalized (-OH) MWCNT nanoparticles. They will be analyzed nanoparticles with different functionalization degrees (4% wt, 6% wt, and 9% wt). In addition, it will be quantified other thermophysical properties (dynamic viscosity, specific heat and specific mass) of the synthetized nanofluids. So, the present work can contribute with experimental data that will help researches in the study and development of MWCNT nanofluids. According to the results, the maximum increment obtained in thermal conductivity was 10.65% in relation to the base fluid (water).
基金Funded by the State Grid Shaanxi Electric Power Company (5226KY17001B)the Natural Science Foundation of Hubei Province (2019CFB787)the State Key Laboratory of New Textile Materials and Advanced Processing Technologies (FZ2020012)。
文摘Because of its merits,acrylic resin was chosen to improve the mechanical,conductive and hydrophobic properties.Carbon fiber powders (CF),carbon nanotubes (MWCNT),and nano-TiO_(2) were incorporated into the acrylic resin to prepare the corona-proof conductive composite coatings.The incorporation of CF and MWCNT may improve the conductivity and mechanical strength of the coatings.However,the addition of nano-TiO_(2) may increase the hydrophobicity of the coatings.Thus,the effects of different additives on the mechanical properties,conductivity,hydrophobicity and heat resistance of the conductive film were studied.The experimental results show that the incorporation of carbon fiber powders and multi walled carbon nanotubes can significantly improve both the conductivity and mechanical properties of the conductive coatings,and the addition of nano titanium dioxide can improve the hydrophobicity of the conductive film.
基金supported by the National Natural Science Foundation of China(Grant Nos.52372241,52072372,591963202,52232007)Hefei Institutes of Physical Science Director’s Fund(Grant Nos.BJPY2023A07,YZJJ-GGZX-2022-01)。
文摘The rapid development of sustainable green energy,which often generates fluctuating electrical signals,has driven the demand for high-performance filter capacitors in alternating/direct current conversion.Replacing bulky aluminum electrolytic capacitors with electric double-layer capacitors(EDLCs)holds promise for electronics miniaturization.However,EDLCs face a trade-off between charge storage ability and ion/electron transport speed.Here,we demonstrate three-dimensional Y-branched carbon tube(3D-YCT)grids with a hierarchically porous structure as electrodes for line-filtering EDLCs.The branching patterns and positions within the 3D-YCT are precisely tailored through the nanochannels inside anodic aluminum oxide templates.These integrated 3D Y-branched CT arrays provide unobstructed pathways for fast frequency response and extensive surfaces for high capacitance.The resulting 3D-YCT-based EDLC achieves a desirable specific areal capacitance(C_(A))of 3.6 mF cm^(-2)with a phase angle of-80°at 120 Hz,outperforming most reported line-filtering EDLCs and demonstrating excellent line-filtering performance.These findings offer valuable insights for constructing miniaturized filter capacitors.
基金support by the Fundamental Research Funds for the Central Universities(No.22120220058)athe Instrumental Analysis Fund of Tongji University(No.2022GX072).
文摘Exploring superior electrocatalyst for hydrogen evolution reaction(HER)is an urgent need for hydrogen production based on water splitting.The redistribution of electrons and the increase of active sites through multi-interface designing of electrocatalyst are powerful strategies to improve the catalytic efficiency.Herein,a three-phase interface structure of N,P co-doped carbon tube embedded with MoO_(2)/Mo_(2)C(MoO_(2)/Mo_(2)C-CT)was fabricated via a cooperative polymerizing-embedding and pyrolysis strategy.Work function and X-ray photoelectron spectroscopy(XPS)verified that the interfacial charge was quantificationally modulated,achieving an intrinsically enhanced charge transfer by an induced built-in electric field.Theoretical study of density functional theory(DFT)illustrated that triple-interface structure showed a lower energy for H*+H2O*than that of single-interface counterparts.The triple-interface MoO_(2)/Mo_(2)C-CT delivered a lower overpotential of 129 mV at 10 mA·cm^(−2)than that of either single-interface MoO_(2)-CT or Mo_(2)C-CT catalyst.This work may put forward an attractive approach for modulating electronic structure and provide insights into the understanding of triple-interface structure towards HER.
基金supported by the National Natural Science Foundation of China(Nos.91963202,52072372,and 52232007).
文摘The rational design of electrodes is the key to achieving ultrahigh-power performance in electrochemical energy storage devices.Recently,we have constructed well-organized and integrated three-dimensional(3D)carbon tube(CT)grids(3D-CTGs)using a 3D porous anodic aluminum oxide template-assisted method as electrodes of electrical double-layer capacitors(EDLCs),showing excellent frequency response performance.The unique design warrants fast ion migration channels,excellent electronic conductivity,and good structural stability.This study achieved one of the highest carbon-based ultrahigh-power EDLCs with the 3D-CTG electrodes,resulting in ultrahigh power of 437 and 1708 W·cm−3 with aqueous and organic electrolytes,respectively.Capacitors constructed with these electrodes would have important application prospects in the ultrahigh-power output.The rational design and fabrication of the 3D-CTGs electrodes have demonstrated their capability to build capacitors with ultrahighpower performance and open up new possibilities for applications requiring high-power output.
基金supported by the National Key Research and Development Program of China(2022YFE0138900)National Natural Science Foundation of China(21972017)+2 种基金the Fundamental Research Funds for the Central Universities(2232022D-18,CUSF-DH-T-2023061)Shanghai Sailing Program(22YF1400700)the Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission(22CGA37).
文摘Rechargeable Zn-air batteries(ZABs)have received extensive attention,while their real applications are highly restricted by the slow kinetics of the oxygen reduction and oxygen evolution reactions(ORR/OER).Herein,we report a“bridge”structured flexible self-supporting bifunctional oxygen electrode(CNT@Co-CNFF50-900)with strong active and stable Co-N/C@pyridine N/C@CNTs reaction centers.Benefiting from the electron distribution optimization and the advantages of hierarchical catalytic design,the CNT@Co-CNF_(F50-900)electrode had superior ORR/OER activity with a small potential gap(ΔE)of 0.74 V.Reinforced by highly graphitized carbon and the“π-π”bond,the free-standing CNT@Co-CNFF50-900 electrode exhibited outstanding catalytic stability with only 36 mV attenuation.Impressively,the CNT@Co-CNFF50-900-based liquid ZAB showed a high power density of 371 mW cm^(−2),a high energy density of 894 Wh kg^(−1),and a long cycling life of over 130 h.The assembled quasi-solid-state ZAB also demonstrated a high power density,attaining 81 mW cm^(−2),with excellent charge-discharge durability beyond 100 h and extremely high flexibility under the multi-angle application.This study provides an effective electrospinning solution for integrating high-efficiency electrocatalysts and electrodes for energy storage and conversion devices.
