Nanoconfinement is a promising approach to simultaneously enhance the thermodynamics,kinetics,and cycling stability of hydrogen storage materials.The introduction of supporting scaffolds usually causes a reduction in ...Nanoconfinement is a promising approach to simultaneously enhance the thermodynamics,kinetics,and cycling stability of hydrogen storage materials.The introduction of supporting scaffolds usually causes a reduction in the total hydrogen storage capacity due to“dead weight.”Here,we synthesize an optimized N-doped porous carbon(rN-pC)without heavy metal as supporting scaffold to confine Mg/MgH_(2) nanoparticles(Mg/MgH_(2)@rN-pC).rN-pC with 60 wt%loading capacity of Mg(denoted as 60 Mg@rN-pC)can adsorb and desorb 0.62 wt%H_(2) on the rN-pC scaffold.The nanoconfined MgH_(2) can be chemically dehydrided at 175℃,providing~3.59 wt%H_(2) with fast kinetics(fully dehydrogenated at 300℃ within 15 min).This study presents the first realization of nanoconfined Mg-based system with adsorption-active scaffolds.Besides,the nanoconfined MgH_(2) formation enthalpy is reduced to~68 kJ mol^(−1) H_(2) from~75 kJ mol^(−1) H_(2) for pure MgH_(2).The composite can be also compressed to nanostructured pellets,with volumetric H_(2) density reaching 33.4 g L^(−1) after 500 MPa compression pressure,which surpasses the 24 g L^(−1) volumetric capacity of 350 bar compressed H_(2).Our approach can be implemented to the design of hybrid H_(2) storage materials with enhanced capacity and desorption rate.展开更多
Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via lo...Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via low-temperature coprecipitation,exhibiting excellent performance for the selective hydrogenation of 5-hydroxymethylfurfural(HMF).A linear correlation is first observed between solvent polarity(E_(T)(30))and product selectivity within both polar aprotic and protic solvent classes,suggesting that solvent properties play a vital role in directing reaction pathways.Among these,1,4-dioxane(aprotic)favors the formation of 2,5-bis(hydroxymethyl)furan(BHMF)with 97.5%selectivity,while isopropanol(iPrOH,protic)promotes 2,5-dimethylfuran production with up to 99.5%selectivity.Mechanistic investigations further reveal that beyond polarity,proton-donating ability is critical in facilitating hydrodeoxygenation.iPrOH enables a hydrogen shuttle mechanism where protons assist in hydroxyl group removal,lowering the activation barrier.In contrast,1,4-dioxane,lacking hydrogen bond donors,stabilizes BHMF and hinders further conversion.Density functional theory calculations confirm a lower activation energy in iPrOH(0.60 eV)compared to 1,4-dioxane(1.07 eV).This work offers mechanistic insights and a practical strategy for solvent-mediated control of product selectivity in biomass hydrogenation,highlighting the decisive role of solvent-catalyst-substrate interactions.展开更多
Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspher...Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspheres.And modification of the pore structure is one of the effective strategies.In this study,multi-cavity mesoporous carbon microspheres were successfully synthesized by the synergistic method of soft and hard templates,during which a phenolic resin with superior thermal stability was employed as the carbon precursor and a mixture of silica sol and F108 as the mesoporous template.Carbon microspheres with multi-cavity mesoporous structures were prepared,and all the samples showed highly even mesopores,with diameters around 12 nm.The diameter of these microspheres decreased from 396.8 nm to about 182.5 nm with the increase of silica sol.After CO_(2) activation,these novel carbon microspheres(APCF0.5-S1.75)demonstrated high specific surface area(983.3 m^(2)/g)and remarkable CO_(2) uptake of 4.93 mmol/g at 0℃ and1 bar.This could be attributed to the unique multi-cavity structure,which offers uniform mesoporous pore channels,minimal CO_(2) transport of and a greater number of active sites for CO_(2) adsorption.展开更多
As a class of crystalline porous materials,metal-organic frameworks(MOFs)have shown unique advantages in the fields of catalysis,gas storage and separation,but their inherent microporous structure(pore diameter<2 n...As a class of crystalline porous materials,metal-organic frameworks(MOFs)have shown unique advantages in the fields of catalysis,gas storage and separation,but their inherent microporous structure(pore diameter<2 nm)severely limits their application in scenarios such as macromolecular mass transfer and so on.In order to overcome this re-striction,mesoporous MOFs(meso-MOFs)with a larger aperture(2-50 nm)have attracted much attention due to their potential applications in biological macromolecular catalysis,energy storage and other fields.To date,how to accurately regulate its mesopore topology and pore ordering still faces important technical challenges.展开更多
Following the fundamental characteristics of the porosity windbreak,this study suggests a new numerical investigation method for the wind field of the windbreak based on the porous medium physical model.This method ca...Following the fundamental characteristics of the porosity windbreak,this study suggests a new numerical investigation method for the wind field of the windbreak based on the porous medium physical model.This method can transform the reasonable matching problem of the porosity and windproof performance of the windbreak into a study of the relationship between the resistance coefficient of the porous medium and the aerodynamic load of the train.This study examines the influence of the hole type on the wind field behind the porosity windbreak.Then,the relationship between the resistance coefficient of the porous medium,the porosity of the windbreak,and the aerodynamic loads of the train is investigated.The results show that the porous media physical model can be used instead of the windbreak geometry to study the windbreak-train aerodynamic performance,and the process of using this method is suggested.展开更多
The study considers numerical findings regarding magneto-thermosolutal-aided natural convective flow of alumina/water-based nanofluid filled in a non-Darcian porous horizontal concentric annulus.Two equations are assu...The study considers numerical findings regarding magneto-thermosolutal-aided natural convective flow of alumina/water-based nanofluid filled in a non-Darcian porous horizontal concentric annulus.Two equations are assumed to evaluate the thermal fields in the porous medium under Local Thermal Non-Equilibrium(LTNE)conditions,along with the Darcy-Brinkman-Forchheimer model for the flow.By imposing distinct and constant temperatures and concentrations on both internal and external cylinders,thermosolutal natural convection is induced in the annulus.We apply the finite volume method to solve the dimensionless governing equations numerically.The thermal conductivity and viscosity of the nanofluid mixture are determined utilizing Corcione’s empirical correlations,incorporating the effects of Brownian diffusion of nanoparticles.Steady-state findings are provided for a range of significant parameters,including buoyancy ratio(N=1 to 5),Lewis(Le=0 to 10),Rayleigh(Ra=102 to 105),Hartmann(Ha=0 to 50),and heat generation in the nanofluid and solid phases(Q=0 to 20)when the nanofluid flow is driven by aiding thermal and mass buoyancies at given porous medium characteristics(porosity(ε),Darcy number(Da),porous interfacial heat transfer coefficient(H),and thermal conductivity ratio(γ),to assess the thermosolutal convective circulation beside heat and solutal transfer rates in the annulus.The results reveal that internal heat generation significantly modifies the heat transport mechanism,initially reducing and then enhancing heat transfer rates as Q increases.Interestingly,increasing Le reduces heat transfer at low Q but promotes it when Q>5,while mass transfer consistently increases with Le.The magnetic field represses heat transfer in the absence of internal heat but enhances it when internal heat is present.展开更多
To efficiently address the current high cost associated with preparing pseudo-boehmite from organic aluminum,a low-cost alternative,AlCl_(3),is employed as the raw material.The sol-gel method is utilized,and H_(2)O_(2...To efficiently address the current high cost associated with preparing pseudo-boehmite from organic aluminum,a low-cost alternative,AlCl_(3),is employed as the raw material.The sol-gel method is utilized,and H_(2)O_(2)is incorporated for the modification of pseudo-boehmite.The modification mechanism is thoroughly investigated through the use of X-ray powder diffractometer,scanning electron microscope,and BET data analysis,as well as molecular dynamics simulations.Under specific conditions(temperature at 80°C,pH=7,and H_(2)O_(2)volume ratios of 0.5:1,1:1,and 2:1),mesoporous pseudo-boehmite is synthesized with a specific surface area of 227 m^(2)/g,a pore volume of 0.281 cm^(3)/g,a pore size of 6.78 nm,and a peptizing index of 99.47%.A novel and innovative methodology for the cost-effective production of high-performance alumina is offered through the approach.展开更多
The use of visible-light responsive photocatalysts for removing heavy metal ions in wastewater has received great attention.However,the development of photocatalysts with high activity and recyclability remains a huge...The use of visible-light responsive photocatalysts for removing heavy metal ions in wastewater has received great attention.However,the development of photocatalysts with high activity and recyclability remains a huge challenge.Herein,a recyclable carbon fiber cloth-supported porous CdS nanorod photocatalyst was fabricated by a two-step hydrothermal treatment using AgVO_(3) nanowires as templates.The results indicated that under visible-light illumination,the carbon cloth-supported porous CdS nanorods showed improved photocatalytic activity for the reduction of Cr(Ⅵ),with an apparent rate constant exceeding that of carbon cloth-supported CdS nanospheres by a factor of 1.65 times.Moreover,the carbon cloth-supported porous CdS nanorods can be easily separated and be reused.This brings a new perspective for developing photocatalysts with high efficiency and recyclability for wastewater treatment.展开更多
This paper gives an overview on nonlinear porous flow in low permeability porous media, reveals the microscopic mechanisms of flows, and clarifies properties of porous flow fluids. It shows that, deviating from Darcy...This paper gives an overview on nonlinear porous flow in low permeability porous media, reveals the microscopic mechanisms of flows, and clarifies properties of porous flow fluids. It shows that, deviating from Darcy＇s linear law, the porous flow characteristics obey a nonlinear law in a low-permeability porous medium, and the viscosity of the porous flow fluid and the permeability values of water and oil are not constants. Based on these characters, a new porous flow model, which can better describe low permeability reservoir~ is established. This model can describe various patterns of porous flow, as Darcy＇s linear law does. All the parameters involved in the model, having definite physical meanings, can be obtained directly from the experiments.展开更多
Large-scale deployment of carbon dioxide(CO_(2))removal technology is an essential step to cope with global warming and achieve carbon neutrality.Direct air capture(DAC)has recently received increasing attention given...Large-scale deployment of carbon dioxide(CO_(2))removal technology is an essential step to cope with global warming and achieve carbon neutrality.Direct air capture(DAC)has recently received increasing attention given the high flexibility to remove CO_(2)from discrete sources.Porous materials with adjustable pore characteristics are promising sorbents with low or no latent heat of vaporization.This review article has summarized the recent development of porous sorbents for DAC,with a focus of pore engineering strategy and adsorption mechanism.Physisorbents such as zeolites,porous carbons,metal-organic frameworks(MOFs),and amine-modified chemisorbents have been discussed and their challenges in practical application have been analyzed.At last,future directions have been proposed,and it is expected to inspire collaborations from chemistry,environment,material science and engineering communities.展开更多
Due to the greenhouse effect caused by carbon dioxide(CO_(2))emission,much attention has been paid for the removal of CO_(2).Porous liquids(PLs),as new type of liquid materials,have obvious advantages in mass and heat...Due to the greenhouse effect caused by carbon dioxide(CO_(2))emission,much attention has been paid for the removal of CO_(2).Porous liquids(PLs),as new type of liquid materials,have obvious advantages in mass and heat transfer,which are widely used in gas adsorption and sep-aration.Metal–organic frameworks(MOFs)with merits like large surface area,inherent porous structure and adjustable topology have been considered as one of the best candidates for PLs construction.This review presents the state-of-the-art status on the fabrication strategy of MOFs-based PLs and their CO_(2) absorption and utilization performance,and the positive effects of porosity and functional modification on the absorption-desorption property,selectivity of target product,and regeneration ability are well summarized.Finally,the challenges and prospects for MOFs-based PLs in the optimization of preparation,the coupling of multiple removal techniques,the in situ characterization methods,the regeneration and cycle stability,the environmental impact as well as expansion of application are proposed.展开更多
The current artificial bone is unable to accurately replicate the inhomogeneity and anisotropy of human cancellous bone.To address this issue,we proposed a personalized approach based on clinical CT images to design m...The current artificial bone is unable to accurately replicate the inhomogeneity and anisotropy of human cancellous bone.To address this issue,we proposed a personalized approach based on clinical CT images to design mechanical equivalent porous structures for artificial femoral heads.Firstly,supported by Micro and clinical CT scans of 21 bone specimens,the anisotropic mechanical parameters of human cancellous bone in the femoral head were characterized using clinical CT values(Hounsfield unit).After that,the equivalent porous structure of cancellous bone was designed based on the gyroid surface,the influence of its degree of anisotropy and volume fraction on the macroscopic mechanical parameters was investigated by finite element analysis.Furthermore,a mapping relationship between CT values and the porous structure was established by jointly solving the mechanical parameters of the porous structure and human cancellous bone,allowing the design of personalized gradient porous structures based on clinical CT images.Finally,to verify the mechanical equivalence,implant press-in tests were conducted on 3D-printed artificial femoral heads and human femoral heads,the influence of the porous structure’s cell size in bone-implant interaction problems was also explored.Results showed that the minimum deviations of press-in stiffness(<15%)and peak load(<5%)both occurred when the cell size was 20%to 30%of the implant diameter.In conclusion,the designed porous structure can replicate the human cancellous bone-implant interaction at a high level,indicating its effectiveness in optimizing the mechanical performance of 3D-printed artificial femoral head.展开更多
Herein,an external crosslinker facilitated the hypercrosslinking of ferrocene and a nitrogen heterocyclic compound(either melamine or imidazole)through a direct Friedel-Crafts reaction,which led to the formation of ni...Herein,an external crosslinker facilitated the hypercrosslinking of ferrocene and a nitrogen heterocyclic compound(either melamine or imidazole)through a direct Friedel-Crafts reaction,which led to the formation of nitrogen-containing hypercrosslinked fer-rocene polymer precursors(HCP-FCs).Subsequent carbonization of these precursors results in the production of iron-nitrogen-doped por-ous carbon absorbers(Fe-NPCs).The Fe-NPCs demonstrate a porous structure comprising aggregated nanotubes and nanospheres.The porosity of this structure can be modulated by adjusting the iron and nitrogen contents to optimize impedance matching.The uniform dis-tribution of Fe-N_(x)C,N dipoles,andα-Fe within the carbon matrix can be ensured by using hypercrosslinked ferrocenes in constructing porous carbon,providing the absorber with numerous polarization sites and a conductive network.The electromagnetic wave absorption performance of the specially designed Fe-NPC-M_(2)absorbers is satisfactory,revealing a minimum reflection loss of-55.3 dB at 2.5 mm and an effective absorption bandwidth of 6.00 GHz at 2.0 mm.By utilizing hypercrosslinked polymers(HCPs)as precursors,a novel method for developing highly efficient carbon-based absorbing agents is introduced in this research.展开更多
Forced imbibition,the invasion of a wetting fluid into porous rocks,plays an important role in the effective exploitation of hydrocarbon resources and the geological sequestration of carbon dioxide.However,the interfa...Forced imbibition,the invasion of a wetting fluid into porous rocks,plays an important role in the effective exploitation of hydrocarbon resources and the geological sequestration of carbon dioxide.However,the interface dynamics influenced by complex topology commonly leads to non-wetting fluid trapping.Particularly,the underlying mechanisms under viscously unfavorable conditions remain unclear.This study employs a direct numerical simulation method to simulate forced imbibition through the reconstructed digital rocks of sandstone.The interface dynamics and fluid–fluid interactions are investigated through transient simulations,while the pore topology metrics are introduced to analyze the impact on steady-state residual fluid distribution obtained by a pseudo-transient scheme.The results show that the cooperative pore-filling process promoted by corner flow is dominant at low capillary numbers.This leads to unstable inlet pressure,mass flow,and interface curvature,which correspond to complicated interface dynamics and higher residual fluid saturation.During forced imbibition,the interface curvature gradually increases,with the pore-filling mechanisms involving the cooperation of main terminal meniscus movement and arc menisci filling.Complex topology with small diameter pores may result in the destabilization of interface curvature.The residual fluid saturation is negatively correlated with porosity and pore throat size,and positively correlated with tortuosity and aspect ratio.A large mean coordination number characterizing global connectivity promotes imbibition.However,high connectivity characterized by the standardized Euler number corresponding to small pores is associated with a high probability of non-wetting fluid trapping.展开更多
Porous carbons hold broad application prospects in the domains of electrochemical energy storage devices and sensors.In this study,porous carbon derived from sodium alginate-encapsulated ZIF-8(SA/ZIF-8-C)was suc-cessf...Porous carbons hold broad application prospects in the domains of electrochemical energy storage devices and sensors.In this study,porous carbon derived from sodium alginate-encapsulated ZIF-8(SA/ZIF-8-C)was suc-cessfully prepared by blending ZIF-8 particles with sodium alginate,forming hydrogel beads in the presence of divalent metal ions,and subsequently subjecting them to high-temperature pyrolysis.Various characterization techniques were employed to evaluate the properties of the prepared materials.The introduction of a carbon framework on ZIF-8-derived particles effectively enhanced the conductivity of the prepared materials.The SA/ZIF-8(1.0)-C sample heated at 800℃exhibited a specific capacitance of up to 208 F g^(-1)at a current density of 0.5 A g^(-1)and outstanding cyclic stability.Even after 10,000 charge and discharge cycles,its capacitance retention rate remained as high as 87.14%.The symmetric supercapacitor constructed with the composite demonstrated an excellent energy density of 14.58 Wh kg^(-1)at a power capacity of 403.85 W kg^(-1).The implementation of this study provides new ideas and inspiration for the development of high-performance supercapacitors.展开更多
The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(S...The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(SiC_(nws))/SiC composites are fabricated with in-situ SiC interface on one-dimensional oriented SiC_(nws)skeleton,which collaborative configuration by 3D printing and freeze casting assembly.The con-structed porous structure optimizes the impedance matching degree and scattering intensity,the maximum effective absorption bandwidth(EAB_(max))of 5.9 GHz and the minimum reflection loss(RL_(min))of−41.4 dB can be realized.Considering the inherent oxidation resistance of SiC,the composites present well-maintained absorption performance at 600℃.Even at 1100℃,the EAB_(max)of 4.9 GHz and RLmin of−30.4 dB also demonstrate the high-temperature absorption stability of the composites,indicating exceptional wave absorption properties and thermal stability.The slight attenuation can be attributed to the decrease in impedance matching capability accompanying the elevated dielectric constant.This work clarifies the impact of structure and component synergy on wave absorption behavior,and offers a novel approach to producing high-performance and high-temperature resistance ceramic-based electromagnetic wave absorption materials suitable for extreme environments.展开更多
The urgent demand for renewable energy solutions,propelled by the global energy crisis and environmental concerns,has spurred the creation of innovative materials for solar thermal storage.Photothermal phase change ma...The urgent demand for renewable energy solutions,propelled by the global energy crisis and environmental concerns,has spurred the creation of innovative materials for solar thermal storage.Photothermal phase change materials(PTPCMs)represent a novel type of composite phase change material(PCM)aimed at improving thermal storage efficiency by incorporating photothermal materials into traditional PCMs and encapsulating them within porous structures.Various porous encapsulation materials have been studied,including porous carbon,expanded graphite,and ceramics,but issues like brittleness hinder their practical use.To overcome these limitations,flexible PTPCMs using organic porous polymers—like foams,hydrogels,and porous wood—have emerged,offering high porosity and lightweight characteristics.This review examines recent advancements in the preparation of PTPCMs based on porous polymer supports through techniques like impregnation and in situ polymerization,assessing the impact of different porous polymer materials on PCM performance and clarifying the mechanisms of photothermal conversion and heat storage.Subsequently,the most recent advancements in the applications of porous polymer-based PTPCMs are systematically summarized,and future research challenges and possible solutions are discussed.This review aims to foster awareness about the potential of PTPCMs in promoting environmentally friendly energy practices and catalyzing further research in this promising field.展开更多
High-concentration single-atom doping remains a formidable challenge due to the propensity for single atoms to form clusters or aggregate at elevated concentrations.Herein,high-concentration (10.8 wt%) Zn singleatom-d...High-concentration single-atom doping remains a formidable challenge due to the propensity for single atoms to form clusters or aggregate at elevated concentrations.Herein,high-concentration (10.8 wt%) Zn singleatom-doped porous tubular g-C_(3)N_(4)(ZCN) was successfully obtained via a template-free,one-step calcination method,exhibiting excellent photocatalytic performance.The confinement of the pore walls suppresses the Zn atom'smigration and aggregation,enhancing the Zn single-atom stability.ZCN exhibited excellent photodegradation performance against tetracycline with outstanding stability.Moreover,ZCN displayed remarkable sterilization performance,achieving a 100%inactivation of Staphylococcus aureus within 90 min of visible-light exposure.Density functional theory calculations demonstrated that the Zn single-atom sites act as pivotal photocatalytic active sites,with the presence of Zn single atoms notably augmenting charge separation efficiency.This work provides a novel approach for managing photocatalytic efficiency through enlarging single-atom doping,offering an avenue for pollutant photodegradation and sterilization.展开更多
Current modifications of Ti-based materials with porous scaffolds for achieving biological fixation often decrease corrosion fatigue strength(σ_(cf))of the resultant implants,thereby shortening their service lifes-pa...Current modifications of Ti-based materials with porous scaffolds for achieving biological fixation often decrease corrosion fatigue strength(σ_(cf))of the resultant implants,thereby shortening their service lifes-pan.To resolve this issue,in the present,a step-wise graded porous Ti-6Al-7Nb scaffold was additively manufactured on optimally surface mechanical attrition treated(SMATed)Ti-6Al-7Nb(specifically de-noted as S-Ti6Al7Nb)using laser powder bed fusion(PBF)technology.The microstructure,bond strength,residual stress distribution,and corrosion fatigue behavior of porous scaffolds modified S-Ti6Al7Nb were investigated and compared with those of mechanically polished Ti-6Al-7Nb(P-Ti6Al7Nb),S-Ti6Al7Nb,and porous scaffolds modified P-Ti6Al7Nb.Results showed that corrosion fatigue of porous scaffolds modi-fied Ti-6Al-7Nb was propagation controlled.Moreover,the crack propagation behavior in the PBF scaf-fold’s fusion zone(FZ)and heat-affected zone(HAZ),exhibiting insensitivity to the microstructural con-figurations characterized by columnar prior-βgrain(PBG)boundaries and acicularα''martensites,cou-pled with the PBF-induced residual tensile stresses in these regions,resulted in a considerable decrease inσ_(cf) for porous scaffolds modified P-Ti6Al7Nb compared to P-Ti6Al7Nb.In contrast,step-wise graded porous scaffold-modified S-Ti6Al7Nb demonstrated an improvedσ_(cf) which was even higher than that of P-Ti6Al7Nb.Such an advancement in corrosion fatigue strength is primarily attributed to the presence of residual compressive stresses within the underlying S-Ti6Al7Nb substrate,extending beyond FZ and HAZ.These stresses increased the crack propagation threshold,leading to crack deflection/branching and increased crack-path tortuosity,thereby synergistically markedly enhancing the crack propagation resis-tance of porous scaffolds modified S-Ti6Al7Nb.展开更多
Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific capacities.However,the inferior intrinsic conductivity and large volume variation d...Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific capacities.However,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs anode.Herein,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for SIBs.Moreover,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 cycles.This work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.展开更多
基金supported by the National Key R&D Program of China(2022YFB3803700)National Natural Science Foundation of China(52171186)+1 种基金Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)support from“Zhiyuan Honor Program”for doctoral students,Shanghai Jiao Tong University.
文摘Nanoconfinement is a promising approach to simultaneously enhance the thermodynamics,kinetics,and cycling stability of hydrogen storage materials.The introduction of supporting scaffolds usually causes a reduction in the total hydrogen storage capacity due to“dead weight.”Here,we synthesize an optimized N-doped porous carbon(rN-pC)without heavy metal as supporting scaffold to confine Mg/MgH_(2) nanoparticles(Mg/MgH_(2)@rN-pC).rN-pC with 60 wt%loading capacity of Mg(denoted as 60 Mg@rN-pC)can adsorb and desorb 0.62 wt%H_(2) on the rN-pC scaffold.The nanoconfined MgH_(2) can be chemically dehydrided at 175℃,providing~3.59 wt%H_(2) with fast kinetics(fully dehydrogenated at 300℃ within 15 min).This study presents the first realization of nanoconfined Mg-based system with adsorption-active scaffolds.Besides,the nanoconfined MgH_(2) formation enthalpy is reduced to~68 kJ mol^(−1) H_(2) from~75 kJ mol^(−1) H_(2) for pure MgH_(2).The composite can be also compressed to nanostructured pellets,with volumetric H_(2) density reaching 33.4 g L^(−1) after 500 MPa compression pressure,which surpasses the 24 g L^(−1) volumetric capacity of 350 bar compressed H_(2).Our approach can be implemented to the design of hybrid H_(2) storage materials with enhanced capacity and desorption rate.
基金the National Nature Science Foundation of China for Excellent Young Scientists Fund(32222058)Fundamental Research Foundation of CAF(CAFYBB2022QB001).
文摘Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via low-temperature coprecipitation,exhibiting excellent performance for the selective hydrogenation of 5-hydroxymethylfurfural(HMF).A linear correlation is first observed between solvent polarity(E_(T)(30))and product selectivity within both polar aprotic and protic solvent classes,suggesting that solvent properties play a vital role in directing reaction pathways.Among these,1,4-dioxane(aprotic)favors the formation of 2,5-bis(hydroxymethyl)furan(BHMF)with 97.5%selectivity,while isopropanol(iPrOH,protic)promotes 2,5-dimethylfuran production with up to 99.5%selectivity.Mechanistic investigations further reveal that beyond polarity,proton-donating ability is critical in facilitating hydrodeoxygenation.iPrOH enables a hydrogen shuttle mechanism where protons assist in hydroxyl group removal,lowering the activation barrier.In contrast,1,4-dioxane,lacking hydrogen bond donors,stabilizes BHMF and hinders further conversion.Density functional theory calculations confirm a lower activation energy in iPrOH(0.60 eV)compared to 1,4-dioxane(1.07 eV).This work offers mechanistic insights and a practical strategy for solvent-mediated control of product selectivity in biomass hydrogenation,highlighting the decisive role of solvent-catalyst-substrate interactions.
基金supported by the National Key R&D Program of China(No.2021YFB3501102).
文摘Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspheres.And modification of the pore structure is one of the effective strategies.In this study,multi-cavity mesoporous carbon microspheres were successfully synthesized by the synergistic method of soft and hard templates,during which a phenolic resin with superior thermal stability was employed as the carbon precursor and a mixture of silica sol and F108 as the mesoporous template.Carbon microspheres with multi-cavity mesoporous structures were prepared,and all the samples showed highly even mesopores,with diameters around 12 nm.The diameter of these microspheres decreased from 396.8 nm to about 182.5 nm with the increase of silica sol.After CO_(2) activation,these novel carbon microspheres(APCF0.5-S1.75)demonstrated high specific surface area(983.3 m^(2)/g)and remarkable CO_(2) uptake of 4.93 mmol/g at 0℃ and1 bar.This could be attributed to the unique multi-cavity structure,which offers uniform mesoporous pore channels,minimal CO_(2) transport of and a greater number of active sites for CO_(2) adsorption.
基金support from the National Natural Science Foundation of China(22088101,21733003,22365021,22305132)the Inner Mongolia Autonomous Region“Grassland Talents”Project(2024098)+3 种基金the Inner Mongolia Natural Science Foundation Youth Fund(2023QN02014)The Local Talent Project of Inner Mongolia(12000-15042222)the Basic Research Expenses Supported under 45 Years Old of Inner Mongolia(10000-23112101/036)the“Young Academic Talents”Program of Inner Mongolia University 23600-5233706.
文摘As a class of crystalline porous materials,metal-organic frameworks(MOFs)have shown unique advantages in the fields of catalysis,gas storage and separation,but their inherent microporous structure(pore diameter<2 nm)severely limits their application in scenarios such as macromolecular mass transfer and so on.In order to overcome this re-striction,mesoporous MOFs(meso-MOFs)with a larger aperture(2-50 nm)have attracted much attention due to their potential applications in biological macromolecular catalysis,energy storage and other fields.To date,how to accurately regulate its mesopore topology and pore ordering still faces important technical challenges.
基金Projects(52302447,52388102,52372369)supported by the National Natural Science Foundation of China。
文摘Following the fundamental characteristics of the porosity windbreak,this study suggests a new numerical investigation method for the wind field of the windbreak based on the porous medium physical model.This method can transform the reasonable matching problem of the porosity and windproof performance of the windbreak into a study of the relationship between the resistance coefficient of the porous medium and the aerodynamic load of the train.This study examines the influence of the hole type on the wind field behind the porosity windbreak.Then,the relationship between the resistance coefficient of the porous medium,the porosity of the windbreak,and the aerodynamic loads of the train is investigated.The results show that the porous media physical model can be used instead of the windbreak geometry to study the windbreak-train aerodynamic performance,and the process of using this method is suggested.
基金The authors extend their appreciation to the Deanship of Scientific Research at Northern Border University,Arar,Saudi Arabia,for funding this research work through the project number NBU-FFR-2025-2193-15.
文摘The study considers numerical findings regarding magneto-thermosolutal-aided natural convective flow of alumina/water-based nanofluid filled in a non-Darcian porous horizontal concentric annulus.Two equations are assumed to evaluate the thermal fields in the porous medium under Local Thermal Non-Equilibrium(LTNE)conditions,along with the Darcy-Brinkman-Forchheimer model for the flow.By imposing distinct and constant temperatures and concentrations on both internal and external cylinders,thermosolutal natural convection is induced in the annulus.We apply the finite volume method to solve the dimensionless governing equations numerically.The thermal conductivity and viscosity of the nanofluid mixture are determined utilizing Corcione’s empirical correlations,incorporating the effects of Brownian diffusion of nanoparticles.Steady-state findings are provided for a range of significant parameters,including buoyancy ratio(N=1 to 5),Lewis(Le=0 to 10),Rayleigh(Ra=102 to 105),Hartmann(Ha=0 to 50),and heat generation in the nanofluid and solid phases(Q=0 to 20)when the nanofluid flow is driven by aiding thermal and mass buoyancies at given porous medium characteristics(porosity(ε),Darcy number(Da),porous interfacial heat transfer coefficient(H),and thermal conductivity ratio(γ),to assess the thermosolutal convective circulation beside heat and solutal transfer rates in the annulus.The results reveal that internal heat generation significantly modifies the heat transport mechanism,initially reducing and then enhancing heat transfer rates as Q increases.Interestingly,increasing Le reduces heat transfer at low Q but promotes it when Q>5,while mass transfer consistently increases with Le.The magnetic field represses heat transfer in the absence of internal heat but enhances it when internal heat is present.
基金Funded by the National Natural Science Foundation of China(Nos.22068021 and 52064030)the Yunnan Young and Middle-aged Academic and Technical Leaders Reserve Talent Program of China(No.202305AC160064)the Yunnan Major Scientific and Technological Program of China(Nos.202402AB080004,202202AG050011,and 202202AG050007)。
文摘To efficiently address the current high cost associated with preparing pseudo-boehmite from organic aluminum,a low-cost alternative,AlCl_(3),is employed as the raw material.The sol-gel method is utilized,and H_(2)O_(2)is incorporated for the modification of pseudo-boehmite.The modification mechanism is thoroughly investigated through the use of X-ray powder diffractometer,scanning electron microscope,and BET data analysis,as well as molecular dynamics simulations.Under specific conditions(temperature at 80°C,pH=7,and H_(2)O_(2)volume ratios of 0.5:1,1:1,and 2:1),mesoporous pseudo-boehmite is synthesized with a specific surface area of 227 m^(2)/g,a pore volume of 0.281 cm^(3)/g,a pore size of 6.78 nm,and a peptizing index of 99.47%.A novel and innovative methodology for the cost-effective production of high-performance alumina is offered through the approach.
文摘The use of visible-light responsive photocatalysts for removing heavy metal ions in wastewater has received great attention.However,the development of photocatalysts with high activity and recyclability remains a huge challenge.Herein,a recyclable carbon fiber cloth-supported porous CdS nanorod photocatalyst was fabricated by a two-step hydrothermal treatment using AgVO_(3) nanowires as templates.The results indicated that under visible-light illumination,the carbon cloth-supported porous CdS nanorods showed improved photocatalytic activity for the reduction of Cr(Ⅵ),with an apparent rate constant exceeding that of carbon cloth-supported CdS nanospheres by a factor of 1.65 times.Moreover,the carbon cloth-supported porous CdS nanorods can be easily separated and be reused.This brings a new perspective for developing photocatalysts with high efficiency and recyclability for wastewater treatment.
文摘This paper gives an overview on nonlinear porous flow in low permeability porous media, reveals the microscopic mechanisms of flows, and clarifies properties of porous flow fluids. It shows that, deviating from Darcy＇s linear law, the porous flow characteristics obey a nonlinear law in a low-permeability porous medium, and the viscosity of the porous flow fluid and the permeability values of water and oil are not constants. Based on these characters, a new porous flow model, which can better describe low permeability reservoir~ is established. This model can describe various patterns of porous flow, as Darcy＇s linear law does. All the parameters involved in the model, having definite physical meanings, can be obtained directly from the experiments.
基金financial support from the National Natural Science Foundation of China(Nos.22278011,22225803,22038001 and 22108007)Beijing Natural Science Foundation(No.Z230023)+1 种基金The Science&Technology Project of Beijing Municipal Education Committee(No.KZ201810005004)Beijing Nova Program(No.Z211100002121094)。
文摘Large-scale deployment of carbon dioxide(CO_(2))removal technology is an essential step to cope with global warming and achieve carbon neutrality.Direct air capture(DAC)has recently received increasing attention given the high flexibility to remove CO_(2)from discrete sources.Porous materials with adjustable pore characteristics are promising sorbents with low or no latent heat of vaporization.This review article has summarized the recent development of porous sorbents for DAC,with a focus of pore engineering strategy and adsorption mechanism.Physisorbents such as zeolites,porous carbons,metal-organic frameworks(MOFs),and amine-modified chemisorbents have been discussed and their challenges in practical application have been analyzed.At last,future directions have been proposed,and it is expected to inspire collaborations from chemistry,environment,material science and engineering communities.
基金supported by the Natural Science Foundation of China(22106007 and U23A20120)Beijing Natural Science Foundation(8244060)+2 种基金China Postdoctoral Science Foundation(2023M730143)R&D Program of BeijingMunicipal Education Commission(KZ202210005011)Natural Science Foundation of Hebei Province(B2021208033).
文摘Due to the greenhouse effect caused by carbon dioxide(CO_(2))emission,much attention has been paid for the removal of CO_(2).Porous liquids(PLs),as new type of liquid materials,have obvious advantages in mass and heat transfer,which are widely used in gas adsorption and sep-aration.Metal–organic frameworks(MOFs)with merits like large surface area,inherent porous structure and adjustable topology have been considered as one of the best candidates for PLs construction.This review presents the state-of-the-art status on the fabrication strategy of MOFs-based PLs and their CO_(2) absorption and utilization performance,and the positive effects of porosity and functional modification on the absorption-desorption property,selectivity of target product,and regeneration ability are well summarized.Finally,the challenges and prospects for MOFs-based PLs in the optimization of preparation,the coupling of multiple removal techniques,the in situ characterization methods,the regeneration and cycle stability,the environmental impact as well as expansion of application are proposed.
基金supported by the National Key R&D Program of China(Grant No.2021YFC2501700).
文摘The current artificial bone is unable to accurately replicate the inhomogeneity and anisotropy of human cancellous bone.To address this issue,we proposed a personalized approach based on clinical CT images to design mechanical equivalent porous structures for artificial femoral heads.Firstly,supported by Micro and clinical CT scans of 21 bone specimens,the anisotropic mechanical parameters of human cancellous bone in the femoral head were characterized using clinical CT values(Hounsfield unit).After that,the equivalent porous structure of cancellous bone was designed based on the gyroid surface,the influence of its degree of anisotropy and volume fraction on the macroscopic mechanical parameters was investigated by finite element analysis.Furthermore,a mapping relationship between CT values and the porous structure was established by jointly solving the mechanical parameters of the porous structure and human cancellous bone,allowing the design of personalized gradient porous structures based on clinical CT images.Finally,to verify the mechanical equivalence,implant press-in tests were conducted on 3D-printed artificial femoral heads and human femoral heads,the influence of the porous structure’s cell size in bone-implant interaction problems was also explored.Results showed that the minimum deviations of press-in stiffness(<15%)and peak load(<5%)both occurred when the cell size was 20%to 30%of the implant diameter.In conclusion,the designed porous structure can replicate the human cancellous bone-implant interaction at a high level,indicating its effectiveness in optimizing the mechanical performance of 3D-printed artificial femoral head.
基金supported by the National Natural Science Foundation of China(No.51803041)the University and Local Integration Development Project of Yantai,China(No.2022 XDRHXMXK08).
文摘Herein,an external crosslinker facilitated the hypercrosslinking of ferrocene and a nitrogen heterocyclic compound(either melamine or imidazole)through a direct Friedel-Crafts reaction,which led to the formation of nitrogen-containing hypercrosslinked fer-rocene polymer precursors(HCP-FCs).Subsequent carbonization of these precursors results in the production of iron-nitrogen-doped por-ous carbon absorbers(Fe-NPCs).The Fe-NPCs demonstrate a porous structure comprising aggregated nanotubes and nanospheres.The porosity of this structure can be modulated by adjusting the iron and nitrogen contents to optimize impedance matching.The uniform dis-tribution of Fe-N_(x)C,N dipoles,andα-Fe within the carbon matrix can be ensured by using hypercrosslinked ferrocenes in constructing porous carbon,providing the absorber with numerous polarization sites and a conductive network.The electromagnetic wave absorption performance of the specially designed Fe-NPC-M_(2)absorbers is satisfactory,revealing a minimum reflection loss of-55.3 dB at 2.5 mm and an effective absorption bandwidth of 6.00 GHz at 2.0 mm.By utilizing hypercrosslinked polymers(HCPs)as precursors,a novel method for developing highly efficient carbon-based absorbing agents is introduced in this research.
基金supported by the National Natural Science Foundation of China(Grant Nos.42172159 and 42302143)the Postdoctora Fellowship Program of the China Postdoctoral Science Foundation(CPSF)(Grant No.GZB20230864).
文摘Forced imbibition,the invasion of a wetting fluid into porous rocks,plays an important role in the effective exploitation of hydrocarbon resources and the geological sequestration of carbon dioxide.However,the interface dynamics influenced by complex topology commonly leads to non-wetting fluid trapping.Particularly,the underlying mechanisms under viscously unfavorable conditions remain unclear.This study employs a direct numerical simulation method to simulate forced imbibition through the reconstructed digital rocks of sandstone.The interface dynamics and fluid–fluid interactions are investigated through transient simulations,while the pore topology metrics are introduced to analyze the impact on steady-state residual fluid distribution obtained by a pseudo-transient scheme.The results show that the cooperative pore-filling process promoted by corner flow is dominant at low capillary numbers.This leads to unstable inlet pressure,mass flow,and interface curvature,which correspond to complicated interface dynamics and higher residual fluid saturation.During forced imbibition,the interface curvature gradually increases,with the pore-filling mechanisms involving the cooperation of main terminal meniscus movement and arc menisci filling.Complex topology with small diameter pores may result in the destabilization of interface curvature.The residual fluid saturation is negatively correlated with porosity and pore throat size,and positively correlated with tortuosity and aspect ratio.A large mean coordination number characterizing global connectivity promotes imbibition.However,high connectivity characterized by the standardized Euler number corresponding to small pores is associated with a high probability of non-wetting fluid trapping.
基金supports from the National Natural Science Foundation of China(22075034,22178037,and 22478047)Natural Science Foundation of Liaoning Province of China(2021-MS-303)the China Scholarship Council(CSC No 202008210171).
文摘Porous carbons hold broad application prospects in the domains of electrochemical energy storage devices and sensors.In this study,porous carbon derived from sodium alginate-encapsulated ZIF-8(SA/ZIF-8-C)was suc-cessfully prepared by blending ZIF-8 particles with sodium alginate,forming hydrogel beads in the presence of divalent metal ions,and subsequently subjecting them to high-temperature pyrolysis.Various characterization techniques were employed to evaluate the properties of the prepared materials.The introduction of a carbon framework on ZIF-8-derived particles effectively enhanced the conductivity of the prepared materials.The SA/ZIF-8(1.0)-C sample heated at 800℃exhibited a specific capacitance of up to 208 F g^(-1)at a current density of 0.5 A g^(-1)and outstanding cyclic stability.Even after 10,000 charge and discharge cycles,its capacitance retention rate remained as high as 87.14%.The symmetric supercapacitor constructed with the composite demonstrated an excellent energy density of 14.58 Wh kg^(-1)at a power capacity of 403.85 W kg^(-1).The implementation of this study provides new ideas and inspiration for the development of high-performance supercapacitors.
基金supported by the National Key R&D Program of China(No.2022YFB3707700)National Natural Science Foundation of China(No.52302121)+3 种基金Shanghai Sailing Program(No.23YF1454700)Shanghai Natural Science Foundation(No.23ZR1472700)Shanghai Post-doctoral Excellent Program(No.2022664)Shanghai Science and Technology Innovation Action Plan(No.21511104800).
文摘The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(SiC_(nws))/SiC composites are fabricated with in-situ SiC interface on one-dimensional oriented SiC_(nws)skeleton,which collaborative configuration by 3D printing and freeze casting assembly.The con-structed porous structure optimizes the impedance matching degree and scattering intensity,the maximum effective absorption bandwidth(EAB_(max))of 5.9 GHz and the minimum reflection loss(RL_(min))of−41.4 dB can be realized.Considering the inherent oxidation resistance of SiC,the composites present well-maintained absorption performance at 600℃.Even at 1100℃,the EAB_(max)of 4.9 GHz and RLmin of−30.4 dB also demonstrate the high-temperature absorption stability of the composites,indicating exceptional wave absorption properties and thermal stability.The slight attenuation can be attributed to the decrease in impedance matching capability accompanying the elevated dielectric constant.This work clarifies the impact of structure and component synergy on wave absorption behavior,and offers a novel approach to producing high-performance and high-temperature resistance ceramic-based electromagnetic wave absorption materials suitable for extreme environments.
基金supported by the National Natural Science Foundation of China(No.52103093,52103205)the Taishan Scholar Project of Shandong Province(No.tsqn202312187)+2 种基金the Natural Science Foundation of Shandong Province(ZR2024QE220)the Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001)the Jiangxi Provincial Natural Science Foundation(20232BAB214031,20242BAB25237).
文摘The urgent demand for renewable energy solutions,propelled by the global energy crisis and environmental concerns,has spurred the creation of innovative materials for solar thermal storage.Photothermal phase change materials(PTPCMs)represent a novel type of composite phase change material(PCM)aimed at improving thermal storage efficiency by incorporating photothermal materials into traditional PCMs and encapsulating them within porous structures.Various porous encapsulation materials have been studied,including porous carbon,expanded graphite,and ceramics,but issues like brittleness hinder their practical use.To overcome these limitations,flexible PTPCMs using organic porous polymers—like foams,hydrogels,and porous wood—have emerged,offering high porosity and lightweight characteristics.This review examines recent advancements in the preparation of PTPCMs based on porous polymer supports through techniques like impregnation and in situ polymerization,assessing the impact of different porous polymer materials on PCM performance and clarifying the mechanisms of photothermal conversion and heat storage.Subsequently,the most recent advancements in the applications of porous polymer-based PTPCMs are systematically summarized,and future research challenges and possible solutions are discussed.This review aims to foster awareness about the potential of PTPCMs in promoting environmentally friendly energy practices and catalyzing further research in this promising field.
基金financially supported by the National Key Research and Development Program of China(No.2023YFF0612601)the Key Research and Development Program of Zhejiang Province(No.2023C02038)+2 种基金the Key Research and Development Program of Ningbo(No.2022Z178)China Construction Technology Research and Development Project(No.CSCEC-2021-Z-5)Zhejiang Provincial Natural Science Foundation of China(No.LQ23B010003)
文摘High-concentration single-atom doping remains a formidable challenge due to the propensity for single atoms to form clusters or aggregate at elevated concentrations.Herein,high-concentration (10.8 wt%) Zn singleatom-doped porous tubular g-C_(3)N_(4)(ZCN) was successfully obtained via a template-free,one-step calcination method,exhibiting excellent photocatalytic performance.The confinement of the pore walls suppresses the Zn atom'smigration and aggregation,enhancing the Zn single-atom stability.ZCN exhibited excellent photodegradation performance against tetracycline with outstanding stability.Moreover,ZCN displayed remarkable sterilization performance,achieving a 100%inactivation of Staphylococcus aureus within 90 min of visible-light exposure.Density functional theory calculations demonstrated that the Zn single-atom sites act as pivotal photocatalytic active sites,with the presence of Zn single atoms notably augmenting charge separation efficiency.This work provides a novel approach for managing photocatalytic efficiency through enlarging single-atom doping,offering an avenue for pollutant photodegradation and sterilization.
基金the National Key Research and Development Program of China(Grant No.2023YFC2412600)the National Natural Science Foundation of China(Grant No.51971171)for financially supporting this work.
文摘Current modifications of Ti-based materials with porous scaffolds for achieving biological fixation often decrease corrosion fatigue strength(σ_(cf))of the resultant implants,thereby shortening their service lifes-pan.To resolve this issue,in the present,a step-wise graded porous Ti-6Al-7Nb scaffold was additively manufactured on optimally surface mechanical attrition treated(SMATed)Ti-6Al-7Nb(specifically de-noted as S-Ti6Al7Nb)using laser powder bed fusion(PBF)technology.The microstructure,bond strength,residual stress distribution,and corrosion fatigue behavior of porous scaffolds modified S-Ti6Al7Nb were investigated and compared with those of mechanically polished Ti-6Al-7Nb(P-Ti6Al7Nb),S-Ti6Al7Nb,and porous scaffolds modified P-Ti6Al7Nb.Results showed that corrosion fatigue of porous scaffolds modi-fied Ti-6Al-7Nb was propagation controlled.Moreover,the crack propagation behavior in the PBF scaf-fold’s fusion zone(FZ)and heat-affected zone(HAZ),exhibiting insensitivity to the microstructural con-figurations characterized by columnar prior-βgrain(PBG)boundaries and acicularα''martensites,cou-pled with the PBF-induced residual tensile stresses in these regions,resulted in a considerable decrease inσ_(cf) for porous scaffolds modified P-Ti6Al7Nb compared to P-Ti6Al7Nb.In contrast,step-wise graded porous scaffold-modified S-Ti6Al7Nb demonstrated an improvedσ_(cf) which was even higher than that of P-Ti6Al7Nb.Such an advancement in corrosion fatigue strength is primarily attributed to the presence of residual compressive stresses within the underlying S-Ti6Al7Nb substrate,extending beyond FZ and HAZ.These stresses increased the crack propagation threshold,leading to crack deflection/branching and increased crack-path tortuosity,thereby synergistically markedly enhancing the crack propagation resis-tance of porous scaffolds modified S-Ti6Al7Nb.
基金financially supported by the National Natural Science Foundation of China(Nos.U1904173 and 52272219)the Key Research Projects of Henan Provincial Department of Education(No.19A150043)+2 种基金the Natural Science Foundation of Henan Province(Nos.202300410330 and 222300420276)the Nanhu Scholars Program for Young Scholars of Xinyang Normal Universitythe Xinyang Normal University Analysis&Testing Center。
文摘Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific capacities.However,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs anode.Herein,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for SIBs.Moreover,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 cycles.This work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.
