Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challeng...Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challenges such as structural phase transitions,Na^(+)/vacancy ordering,and Jahn–Teller distortion effect,resulting in severe capacity decay and sluggish ion kinetics.We develop a novel Cu/Y dual-doping strategy that leads to the formation of"Na–Y"interlayer aggregates,which act as structural pillars within alkali metal layers,enhancing structural stability and disrupting the ordered arrangement of Na^(+)/vacancies.This disruption leads to a unique coexistence of ordered and disordered Na^(+)/vacancy states with near-zero strain,which significantly improves Na^(+)diffusion kinetics.This structural innovation not only mitigates the unfavorable P2–O2 phase transition but also facilitates rapid ion transport.As a result,the doped material demonstrates exceptional electrochemical performance,including an ultra-long cycle life of 3000 cycles at 10 C and an outstanding high-rate capability of~70 mAh g^(−1)at 50 C.The discovery of this novel interlayer pillar,along with its role in modulating Na^(+)/vacancy arrangements,provides a fresh perspective on engineering layered oxides.It opens up promising new pathways for the structural design of advanced cathode materials toward efficient,stable,and high-rate SIBs.展开更多
The School of Materials Science and Engineering at Southeast University is nestled along the scenic Jiulong Lake in Nanjing,south of the Yangtze River and west of the Zhongshan Mountains.As early as 1928,Southeast Uni...The School of Materials Science and Engineering at Southeast University is nestled along the scenic Jiulong Lake in Nanjing,south of the Yangtze River and west of the Zhongshan Mountains.As early as 1928,Southeast University(then known as National Central University)introduced undergraduate majors in engineering materials,as well as casting and forging materials.To advance materials science,the university established the Department of Materials Science and Engineering in December 1984,building upon the foundations of metal materials and heat treatment.Over time,majors such as Civil Engineering Materials from the Civil Engineering Department and Advanced Materials Processing from the Mechanical Engineering Department were integrated into this new department.In 2006,the department evolved into the School of Materials Science and Engineering,and in 2017,its Materials Science discipline was recognized as a“Double First-Class”national initiative.展开更多
Peri-implantitis is a bacterial infection that causes soft tissue inflammatory lesions and alveolar bone resorption,ultimately resulting in implant failure.Dental implants for clinical use barely have antibacterial pr...Peri-implantitis is a bacterial infection that causes soft tissue inflammatory lesions and alveolar bone resorption,ultimately resulting in implant failure.Dental implants for clinical use barely have antibacterial properties,and bacterial colonization and biofilm formation on the dental implants are major causes of peri-implantitis.Treatment strategies such as mechanical debridement and antibiotic therapy have been used to remove dental plaque.However,it is particularly important to prevent the occurrence of peri-implantitis rather than treatment.Therefore,the current research spot has focused on improving the antibacterial properties of dental implants,such as the construction of specific micro-nano surface texture,the introduction of diverse functional coatings,or the application of materials with intrinsic antibacterial properties.The aforementioned antibacterial surfaces can be incorporated with bioactive molecules,metallic nanoparticles,or other functional components to further enhance the osteogenic properties and accelerate the healing process.In this review,we summarize the recent developments in biomaterial science and the modification strategies applied to dental implants to inhibit biofilm formation and facilitate bone-implant integration.Furthermore,we summarized the obstacles existing in the process of laboratory research to reach the clinic products,and propose corresponding directions for future developments and research perspectives,so that to provide insights into the rational design and construction of dental implants with the aim to balance antibacterial efficacy,biological safety,and osteogenic property.展开更多
To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretre...To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.展开更多
The influence of Hf on the precipitation behavior of γ'phase and the subsequent tensile properties of a Ni-Cr-Mo alloy after long-term thermal exposure was investigated.The results reveal that the addition of Hf ...The influence of Hf on the precipitation behavior of γ'phase and the subsequent tensile properties of a Ni-Cr-Mo alloy after long-term thermal exposure was investigated.The results reveal that the addition of Hf increases the average diameter ofγ'phases after thermal exposure at 700℃ for 5000 h,which enhances the critical resolved shear stress required for dislocations to shear the γ'phases in the Ni-Cr-Mo alloy.Simultaneously,element Hf incorporated into the γ'phases increases the lattice mismatch between the γ'and γ phase,thereby strengthening the coherency strengthening effect.These two factors collectively contribute to the enhanced strength of the alloy.Thus,Hf alloying effectively improves the yield strength of the Ni-Cr-Mo alloy after thermal exposure at 700℃.展开更多
The water-quenched(WQ)2195 Al−Li alloy was subjected to stretching at different temperatures,from room temperature(RT)to−196℃(CT),to investigate the effect of cryogenic deformation on the aging precipitation behavior...The water-quenched(WQ)2195 Al−Li alloy was subjected to stretching at different temperatures,from room temperature(RT)to−196℃(CT),to investigate the effect of cryogenic deformation on the aging precipitation behaviors and mechanical properties.The precipitation kinetics of the T1 phase and the microstructures in peak aging state were investigated through the differential scanning calorimetric(DSC)tests and electron microscopy observation.The results show that−196℃deformation produces a high dislocation density,which promotes the precipitation of the T1 phase and refines its sizes significantly.In addition,the grain boundary precipitates(GBPs)of−196℃-stretched samples are suppressed considerably due to the high dislocation density in the grain interiors,which increases the ductility.In comparison,the strength remains nearly constant.Thus,it is indicated that cryogenic forming has the potential to provide the shape and property control for the manufacture of critical components of aluminum alloys.展开更多
The microstructural evolution of Cu−19Ni−6Cr−7Mn alloy during aging treatment was investigated.After aging for 120 min at 500℃,the alloy exhibited excellent mechanical properties,including a tensile strength of 978 M...The microstructural evolution of Cu−19Ni−6Cr−7Mn alloy during aging treatment was investigated.After aging for 120 min at 500℃,the alloy exhibited excellent mechanical properties,including a tensile strength of 978 MPa and an elastic modulus of 145.8 GPa.After aging for 240 min at 500℃,the elastic modulus of the alloy reached 149.5 GPa,which was among the highest values reported for Cu alloys.It was worth mentioning that the tensile strength increased rapidly from 740 to 934 MPa after aging for 5 min at 500℃,which was close to the maximum tensile strength(978 MPa).Analysis of the underlying strengthening mechanisms and phase transformation behavior revealed that the Cu−19Ni−6Cr−7Mn alloy underwent spinodal decomposition and DO_(22) ordering during the first 5 min of aging at 500℃,and L1_(2) ordered phases and bcc-Cr precipitates appeared.Therefore,the enhanced mechanical properties of the Cu−19Ni−6Cr−7Mn alloy can be attributed to the stress field generated by spinodal decomposition and the presence of nanoscale ordered phase and Cr precipitates.展开更多
Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,...Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors.展开更多
The age-hardening response,mechanical,and corrosion-resistant properties of AA7085 alloys with and without the addition of 0.3 wt.%scandium(Sc)were compared.Using advanced techniques such as aberration-corrected trans...The age-hardening response,mechanical,and corrosion-resistant properties of AA7085 alloys with and without the addition of 0.3 wt.%scandium(Sc)were compared.Using advanced techniques such as aberration-corrected transmission electron microscopy and first-principles calculations,the underlying micromechanisms of Sc microalloying were revealed.Results show that the increase in strength of the AA7085-Sc alloy is mainly attributed to the decreased Al grain size and increased number density of both Al_(3)Sc@Al_(3)(Sc,Zr)core−shell nanoparticles and Sc-containingη_(p) and GP−η_(p) nanoprecipitates.Strong strain fields and evident electron transfer from Zr to the neighboring matrix Al atoms exist at the Al_(3)Sc@Al_(3)(Sc,Zr)/Al interface.The Sc doping in GP−η_(p) andη_(p) suppresses the GP−η_(p)→η_(p) transformation.Modified corrosion resistance of the AA7085-Sc alloy compared with AA7085 alloy is associated with the fine grain boundary precipitates ofη_(p)hases and narrow precipitation free zone.The reasons of property changes of AA7085 alloy after Sc microalloying are explored based on the multiscale microstructural characterization.展开更多
Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always...Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always struggle to balance mechanical properties and thermal insulation,resulting in their inability to meet the demands for both washing resistance and personal protection.Herein,inspired by the natural spring-like structures of cucumber tendrils,a superelastic and washable micro/nanofibrous sponge(MNFS)based on biomimetic helical fibers is directly prepared utilizing multiple-jet electrospinning technology for high-performance thermal insulation.By regulating the conductivity of polyvinylidene fluoride solution,multiple-jet ejection and multiple-stage whipping of jets are achieved,and further control of phase separation rates enables the rapid solidification of jets to form spring-like helical fibers,which are directly entangled to assemble MNFS.The resulting MNFS exhibits superelasticity that can withstand large tensile strain(200%),1000 cyclic tensile or compression deformations,and retain good resilience even in liquid nitrogen(-196℃).Furthermore,the MNFS shows efficient thermal insulation with low thermal conductivity(24.85 mW m^(-1)K^(-1)),close to the value of dry air,and remains structural stability even after cyclic washing.This work offers new possibilities for advanced fibrous sponges in transportation,environmental,and energy applications.展开更多
Traditional stealth materials do not fulfill the requirements of high absorption for radar waves and low emissivity for infrared waves.Furthermore,they can be detected by various technologies,considerably threatening ...Traditional stealth materials do not fulfill the requirements of high absorption for radar waves and low emissivity for infrared waves.Furthermore,they can be detected by various technologies,considerably threatening weapon safety.Therefore,a stealth material compatible with radar and infrared was designed based on the photonic bandgap characteristics of photonic crystals.The radar stealth lay-er(bottom layer)is a composite of carbonyl iron/silicon dioxide/epoxy resin,and the infrared stealth layer(top layer)is a 1D photonic crystal with alternately and periodically stacked germanium and silicon nitride.Through composition optimization and structural adjust-ment,the effective absorption bandwidth of the compatible stealth material with a reflection loss of less than-10 dB has reached 4.95 GHz.The average infrared emissivity of the proposed design is 0.1063,indicating good stealth performance.The theoretical analysis proves that photonic crystals with this structural design can produce infrared waves within the photonic bandgap,achieving high radar wave transmittance and low infrared emissivity.Infrared stealth is achieved without affecting the absorption performance of the radar stealth layer,and the conflict between radar and infrared stealth performance is resolved.This work aims to promote the application of photonic crystals in compatible stealth materials and the development of stealth technology and to provide a design and theoretical found-ation for related experiments and research.展开更多
Conductive elastomers combining micromechanical sensitivity,lightweight adaptability,and environmental sustainability are critically needed for advanced flexible electronics requiring precise responsiveness and long-t...Conductive elastomers combining micromechanical sensitivity,lightweight adaptability,and environmental sustainability are critically needed for advanced flexible electronics requiring precise responsiveness and long-term wearability;however,the integration of these properties remains a significant challenge.Here,we present a biomass-derived conductive elastomer featuring a rationally engineered dynamic crosslinked network integrated with a tunable microporous architecture.This structural design imparts pronounced micromechanical sensitivity,an ultralow density(~0.25 g cm^(−3)),and superior mechanical compliance for adaptive deformation.Moreover,the unique micro-spring effect derived from the porous architecture ensures exceptional stretchability(>500%elongation at break)and superior resilience,delivering immediate and stable electrical response under both subtle(<1%)and large(>200%)mechanical stimuli.Intrinsic dynamic interactions endow the elastomer with efficient room temperature self-healing and complete recyclability without compromising performance.First-principles simulations clarify the mechanisms behind micropore formation and the resulting functionality.Beyond its facile and mild fabrication process,this work establishes a scalable route toward high-performance,sustainable conductive elastomers tailored for next-generation soft electronics.展开更多
To realize the application of electromagnetic wave absorption(EWA)devices in humid marine environments,bifunctional EWA materials with better EWA capacities and anticorrosion properties have great exploration signific...To realize the application of electromagnetic wave absorption(EWA)devices in humid marine environments,bifunctional EWA materials with better EWA capacities and anticorrosion properties have great exploration significance and systematic research re-quirements.By utilizing the low-cost and excellent magnetic and stable chemical characteristics of barium ferrite(BaFe_(12)O_(19))and using the high dielectric loss and excellent chemical inertia of nanocarbon clusters,a new type of nanocomposites with carbon nanoclusters en-capsulating BaFe_(12)O_(19)was designed and synthesized by combining an impregnation method and a high-temperature calcination strategy.Furthermore,Ce-Mn ions were introduced into the BaFe_(12)O_(19)lattice to improve the dielectric and magnetic properties of BaFe_(12)O_(19)cores significantly,and the energy band structure of the doped lattice and the orders of Ce replacing Fe sites were calculated.Benefiting from Ce-Mn ion doping and carbon nanocluster encapsulation,the composite material exhibited excellent dual functionality of corrosion resist-ance and EWA.When BaCe_(0.2)Mn_(0.3)Fe_(11.5)O_(19)-C(BCM-C)was calcined at 600°C,the minimum reflection loss of-20.1 dB was achieved at 14.43 GHz.The Ku band’s effective absorption bandwidth of 4.25 GHz was achieved at an absorber thickness of only 1.3 mm.The BCM-C/polydimethylsiloxane coating had excellent corrosion resistance in the simulated marine environment(3.5wt%NaCl solution).The|Z|0.01Hz value of BCM-C remained at 106Ω·cm^(2)after 12 soaking days.The successful preparation of the BaFe_(12)O_(19)composite en-capsulated with carbon nanoclusters provides new insights into the preparation of multifunctional absorbent materials and the fabrication of absorbent devices applied in humid marine environments in the future.展开更多
Machine learning-assisted methods for rapid and accurate prediction of temperature field,mushy zone,and grain size were proposed for the heating−cooling combined mold(HCCM)horizontal continuous casting of C70250 alloy...Machine learning-assisted methods for rapid and accurate prediction of temperature field,mushy zone,and grain size were proposed for the heating−cooling combined mold(HCCM)horizontal continuous casting of C70250 alloy plates.First,finite element simulations of casting processes were carried out with various parameters to build a dataset.Subsequently,different machine learning algorithms were employed to achieve high precision in predicting temperature fields,mushy zone locations,mushy zone inclination angle,and billet grain size.Finally,the process parameters were quickly optimized using a strategy consisting of random generation,prediction,and screening,allowing the mushy zone to be controlled to the desired target.The optimized parameters are 1234℃for heating mold temperature,47 mm/min for casting speed,and 10 L/min for cooling water flow rate.The optimized mushy zone is located in the middle of the second heat insulation section and has an inclination angle of roughly 7°.展开更多
Titanium(Ti)and its alloys are frequently utilized as critical components in a variety of engineering ap-plications because of their high specific strength and excellent corrosion resistance.Compared to conven-tional ...Titanium(Ti)and its alloys are frequently utilized as critical components in a variety of engineering ap-plications because of their high specific strength and excellent corrosion resistance.Compared to conven-tional surface strengthening technologies,laser shock peening(LSP)has increasingly attracted attention from researchers and industries,since it significantly improves the surface strength,biocompatibility,fa-tigue resistance,and anti-corrosion ability of Ti and its alloys.Despite numerous studies that have been carried out to elucidate the effects of LSP on microstructural evolution and mechanical properties of Ti and its alloys in recent years,a comprehensive review of recent advancements in the field of Ti and its alloys subjected to LSP is still lacking.In this review,the standard LSP and the novel process designs of LSP assisted by thermal,cryogenic,electropulsing and magnetic fields are discussed and compared.Microstructural evolution,with focuses on the dislocation dynamics,deformation twinning,grain refine-ment and surface amorphization,during LSP processing of Ti alloys is reviewed.Furthermore,the en-hanced engineering performance of the L SP-processed(L SPed)Ti alloys,including surface hardness,wear resistance,fatigue life and corrosion resistance are summarized.Finally,this review concludes by present-ing an overview of the current challenges encountered in this field and offering insights into anticipated future trends.展开更多
A tunable oxidization and reduction strategy was proposed to directly regenerate spent LiFePO_(4)/C cathode materials by oxidizing excessive carbon powders with the addition of FePO_(4).Experimental results indicate t...A tunable oxidization and reduction strategy was proposed to directly regenerate spent LiFePO_(4)/C cathode materials by oxidizing excessive carbon powders with the addition of FePO_(4).Experimental results indicate that spent LiFePO_(4)/C cathode materials with good performance can be regenerated by roasting at 650℃ for 11 h with the addition ofLi_(2)CO_(3),FePO_(4),V_(2)O_(5),and glucose.V_(2)O_(5) is added to improve the cycle performance of regenerated cathode materials.Glucose is used to revitalize the carbon layers on the surface of spent LiFePO_(4)/C particles for improving their conductivity.The regenerated V-doped LiFePO_(4)/C shows an excellent electrochemical performance with the discharge specific capacity of 161.36 mA·h/g at 0.2C,under which the capacity retention is 97.85%after 100 cycles.展开更多
In lithium-sulfur batteries(LSBs),the limited utilization of sulfur and the sluggish kinetics of redox reaction significantly hinder their electrochemical performance,especially under high rates and high sulfur loadin...In lithium-sulfur batteries(LSBs),the limited utilization of sulfur and the sluggish kinetics of redox reaction significantly hinder their electrochemical performance,especially under high rates and high sulfur loadings.Here,we propose a novel separator structure with an interlayer composed of a vermiculite nanosheet combined with Ketjen Black(VMT@KB)for LSBs,facilitating efficient adsorption and rapid catalytic conversion toward lithium polysulfides(LiPSs).The VMT@KB nanosheets with an electrical double-layer structure and electronic conductivity are obtained through a high-temperature peeling process and Li^(+)exchange treatment in LiCl solution,followed by a mechanical combination process with KB.The results demonstrate that incorporating VMT@KB as an interlayer on a conventional separator enhances the conductivity and limits the LiPSs in the cathode region.The Li-S cell with VMT@KB interlayer shows satisfactory cycle and rate performance,especially in high sulfur loading.It exhibits a remarkable initial discharge capacity of 1225 mAh g^(-1)at 0.5 C and maintains a capacity of 816 mAh g^(-1)after 500 cycles.Besides,the discharge capacity remains 462 mAh g^(-1)even at 6 C.Moreover,the cell with high sulfur loading(8.2 mg cm^(-2))enables stable cycling for 100 cycles at 0.1 C with a discharge capacity of over1000 mAh g^(-1).展开更多
Metal-organic frameworks(MOFs)have been widely applied in the field of electromagnetic wave absorption(EMWA)on account of unique morphology,simple fabrication,and ultra-high porosity.Nevertheless,the facile method of ...Metal-organic frameworks(MOFs)have been widely applied in the field of electromagnetic wave absorption(EMWA)on account of unique morphology,simple fabrication,and ultra-high porosity.Nevertheless,the facile method of protecting its structure from being destroyed remains challenging.Herein,we proposed a hydrothermal method combined with a carbonization strategy to construct the 0D/1D/2D Fe_(3)C@NC@Mo_(2)C/Fe_(3)C composites.Owing to the incorporation of polydopamine(PDA),the carbon shell formed during high-temperature carbonization effectively protected the original MIL-88A rod-like structure,and the 2D Mo_(2)C nano-sheets and 1D Fe_(3)C nanoparticles were coated on the surface of 1D Fe_(3)C nanorods.With the increase in carbonization temperature,the EMWA properties of the composites presented a trend of first increasing and then decreasing.Impressively,the composites(at 750℃)exhibited praiseworthy EMWA performances with a minimum reflection loss value of−43.70 dB at 8.00 GHz,alongside a maximum effective absorption bandwidth of 6.08 GHz(11.20-17.28 GHz).Density functional theory calculations confirmed the distinctive charge distribution resulting from the heterointerface,which is beneficial to the polarization loss and conductive loss.As a result,the outstanding EMWA performance was credited to the distinctive hierarchical structure,appropriate impedance matching,numerous heterogeneous interfaces,and magnetic loss.Moreover,Radar cross-section calculations indicated that the composites have tremendous potential for practical application.Thus,this work may pave new avenues for designing high-performance and structure-controllable absorbing materials.展开更多
Due to the small size,active mobility,and intrinsic softness,miniature soft robots hold promising po-tentials in reaching the deep region inside living bodies otherwise inaccessible with compelling agility,adaptabilit...Due to the small size,active mobility,and intrinsic softness,miniature soft robots hold promising po-tentials in reaching the deep region inside living bodies otherwise inaccessible with compelling agility,adaptability and safety.Various materials and actuation strategies have been developed for creating soft robots,among which,ferromagnetic soft materials that self-actuate in response to external magnetic fields have attracted worldwide attention due to their remote controllability and excellent compatibil-ity with biological tissues.This review presents comprehensive and systematic research advancements in the design,fabrication,and applications of ferromagnetic soft materials for miniature robots,providing in-sights into their potential use in biomedical fields and beyond.The programming strategies of ferromag-netic soft materials are summarized and classified,including mold-assisted programming,3D printing-assisted programming,microassembly-assisted programming,and magnetization reprogramming.Each approach possesses unique advantages in manipulating the magnetic responsiveness of ferromagnetic soft materials to achieve outstanding actuation and deformation performances.We then discuss the biomedi-cal applications of ferromagnetic soft material-based soft robots(e.g.,minimally invasive surgery,targeted delivery,and tissue engineering),highlighting their potentials in revolutionizing biomedical technologies.This review also points out the current challenges and provides insights into future research directions,which we hope can serve as a useful reference for the development of next-generation adaptive miniature robots.展开更多
Improving the volumetric energy density of supercapacitors is essential for practical applications,which highly relies on the dense storage of ions in carbon-based electrodes.The functional units of carbon-based elect...Improving the volumetric energy density of supercapacitors is essential for practical applications,which highly relies on the dense storage of ions in carbon-based electrodes.The functional units of carbon-based electrode exhibit multi-scale structural characteristics including macroscopic electrode morphologies,mesoscopic microcrystals and pores,and microscopic defects and dopants in the carbon basal plane.Therefore,the ordered combination of multi-scale structures of carbon electrode is crucial for achieving dense energy storage and high volumetric performance by leveraging the functions of various scale structu re.Considering that previous reviews have focused more on the discussion of specific scale structu re of carbon electrodes,this review takes a multi-scale perspective in which recent progresses regarding the structureperformance relationship,underlying mechanism and directional design of carbon-based multi-scale structures including carbon morphology,pore structure,carbon basal plane micro-environment and electrode technology on dense energy storage and volumetric property of supercapacitors are systematically discussed.We analyzed in detail the effects of the morphology,pore,and micro-environment of carbon electrode materials on ion dense storage,summarized the specific effects of different scale structures on volumetric property and recent research progress,and proposed the mutual influence and trade-off relationship between various scale structures.In addition,the challenges and outlooks for improving the dense storage and volumetric performance of carbon-based supercapacitors are analyzed,which can provide feasible technical reference and guidance for the design and manufacture of dense carbon-based electrode materials.展开更多
基金supported by the“Pioneer”and“Leading Goose”R&D Program of Zhejiang Province of China(No.2024C01056)。
文摘Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challenges such as structural phase transitions,Na^(+)/vacancy ordering,and Jahn–Teller distortion effect,resulting in severe capacity decay and sluggish ion kinetics.We develop a novel Cu/Y dual-doping strategy that leads to the formation of"Na–Y"interlayer aggregates,which act as structural pillars within alkali metal layers,enhancing structural stability and disrupting the ordered arrangement of Na^(+)/vacancies.This disruption leads to a unique coexistence of ordered and disordered Na^(+)/vacancy states with near-zero strain,which significantly improves Na^(+)diffusion kinetics.This structural innovation not only mitigates the unfavorable P2–O2 phase transition but also facilitates rapid ion transport.As a result,the doped material demonstrates exceptional electrochemical performance,including an ultra-long cycle life of 3000 cycles at 10 C and an outstanding high-rate capability of~70 mAh g^(−1)at 50 C.The discovery of this novel interlayer pillar,along with its role in modulating Na^(+)/vacancy arrangements,provides a fresh perspective on engineering layered oxides.It opens up promising new pathways for the structural design of advanced cathode materials toward efficient,stable,and high-rate SIBs.
文摘The School of Materials Science and Engineering at Southeast University is nestled along the scenic Jiulong Lake in Nanjing,south of the Yangtze River and west of the Zhongshan Mountains.As early as 1928,Southeast University(then known as National Central University)introduced undergraduate majors in engineering materials,as well as casting and forging materials.To advance materials science,the university established the Department of Materials Science and Engineering in December 1984,building upon the foundations of metal materials and heat treatment.Over time,majors such as Civil Engineering Materials from the Civil Engineering Department and Advanced Materials Processing from the Mechanical Engineering Department were integrated into this new department.In 2006,the department evolved into the School of Materials Science and Engineering,and in 2017,its Materials Science discipline was recognized as a“Double First-Class”national initiative.
基金supported by the National Key Research and Development Program of China(2023YFC2412600)the National Natural Science Foundation of China(52271243,52171233,82370924,82170929)+3 种基金the Beijing Natural Science Foundation(L212014)the Beijing Nova Program(20230484459)the National Clinical Key Discipline Construction Project(PKUSSNKP-T202103)the Research Foundation of Peking University School and Hospital of Stomatology(PKSS20230104).
文摘Peri-implantitis is a bacterial infection that causes soft tissue inflammatory lesions and alveolar bone resorption,ultimately resulting in implant failure.Dental implants for clinical use barely have antibacterial properties,and bacterial colonization and biofilm formation on the dental implants are major causes of peri-implantitis.Treatment strategies such as mechanical debridement and antibiotic therapy have been used to remove dental plaque.However,it is particularly important to prevent the occurrence of peri-implantitis rather than treatment.Therefore,the current research spot has focused on improving the antibacterial properties of dental implants,such as the construction of specific micro-nano surface texture,the introduction of diverse functional coatings,or the application of materials with intrinsic antibacterial properties.The aforementioned antibacterial surfaces can be incorporated with bioactive molecules,metallic nanoparticles,or other functional components to further enhance the osteogenic properties and accelerate the healing process.In this review,we summarize the recent developments in biomaterial science and the modification strategies applied to dental implants to inhibit biofilm formation and facilitate bone-implant integration.Furthermore,we summarized the obstacles existing in the process of laboratory research to reach the clinic products,and propose corresponding directions for future developments and research perspectives,so that to provide insights into the rational design and construction of dental implants with the aim to balance antibacterial efficacy,biological safety,and osteogenic property.
基金National Natural Science Foundation of China(52071274)Key Research and Development Projects of Shaanxi Province(2023-YBGY-442)Science and Technology Nova Project-Innovative Talent Promotion Program of Shaanxi Province(2020KJXX-062)。
文摘To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.
基金National Key Research and Development Program of China(2021YFB3704103)National Natural Science Foundation of China(51571191)。
文摘The influence of Hf on the precipitation behavior of γ'phase and the subsequent tensile properties of a Ni-Cr-Mo alloy after long-term thermal exposure was investigated.The results reveal that the addition of Hf increases the average diameter ofγ'phases after thermal exposure at 700℃ for 5000 h,which enhances the critical resolved shear stress required for dislocations to shear the γ'phases in the Ni-Cr-Mo alloy.Simultaneously,element Hf incorporated into the γ'phases increases the lattice mismatch between the γ'and γ phase,thereby strengthening the coherency strengthening effect.These two factors collectively contribute to the enhanced strength of the alloy.Thus,Hf alloying effectively improves the yield strength of the Ni-Cr-Mo alloy after thermal exposure at 700℃.
基金financially supported by the National Key Research and Development Program of China (No. 2019YFA0708801)the National Natural Science Foundation of China (No. 51875125)。
文摘The water-quenched(WQ)2195 Al−Li alloy was subjected to stretching at different temperatures,from room temperature(RT)to−196℃(CT),to investigate the effect of cryogenic deformation on the aging precipitation behaviors and mechanical properties.The precipitation kinetics of the T1 phase and the microstructures in peak aging state were investigated through the differential scanning calorimetric(DSC)tests and electron microscopy observation.The results show that−196℃deformation produces a high dislocation density,which promotes the precipitation of the T1 phase and refines its sizes significantly.In addition,the grain boundary precipitates(GBPs)of−196℃-stretched samples are suppressed considerably due to the high dislocation density in the grain interiors,which increases the ductility.In comparison,the strength remains nearly constant.Thus,it is indicated that cryogenic forming has the potential to provide the shape and property control for the manufacture of critical components of aluminum alloys.
基金supported by the National Key R&D Program of China (No. 2021YFB3700700)the Henan Province Top Talent Training Program Project, China (No. 244500510020)the High-level Talent Research Start-up Project Funding of Henan Academy of Sciences, China (No. 242017001)。
文摘The microstructural evolution of Cu−19Ni−6Cr−7Mn alloy during aging treatment was investigated.After aging for 120 min at 500℃,the alloy exhibited excellent mechanical properties,including a tensile strength of 978 MPa and an elastic modulus of 145.8 GPa.After aging for 240 min at 500℃,the elastic modulus of the alloy reached 149.5 GPa,which was among the highest values reported for Cu alloys.It was worth mentioning that the tensile strength increased rapidly from 740 to 934 MPa after aging for 5 min at 500℃,which was close to the maximum tensile strength(978 MPa).Analysis of the underlying strengthening mechanisms and phase transformation behavior revealed that the Cu−19Ni−6Cr−7Mn alloy underwent spinodal decomposition and DO_(22) ordering during the first 5 min of aging at 500℃,and L1_(2) ordered phases and bcc-Cr precipitates appeared.Therefore,the enhanced mechanical properties of the Cu−19Ni−6Cr−7Mn alloy can be attributed to the stress field generated by spinodal decomposition and the presence of nanoscale ordered phase and Cr precipitates.
基金supported by the National Key Research and Development Program of China(2024YFA1612900)the National Natural Science Foundation of China(Grant No.52103365 and No.12375270)the Guangdong Innovative and Entrepreneurial Research Team Program,China(Grant No.2021ZT09L227).
文摘Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors.
基金the support from the National Natural Science Foundation of China (Nos. U20A20274, 52061003)the Natural Science Foundation of Yunnan Province, China (No. 202301AT070209)the Science and Technology Major Project of Yunnan Province, China (No. 202102AG050017)。
文摘The age-hardening response,mechanical,and corrosion-resistant properties of AA7085 alloys with and without the addition of 0.3 wt.%scandium(Sc)were compared.Using advanced techniques such as aberration-corrected transmission electron microscopy and first-principles calculations,the underlying micromechanisms of Sc microalloying were revealed.Results show that the increase in strength of the AA7085-Sc alloy is mainly attributed to the decreased Al grain size and increased number density of both Al_(3)Sc@Al_(3)(Sc,Zr)core−shell nanoparticles and Sc-containingη_(p) and GP−η_(p) nanoprecipitates.Strong strain fields and evident electron transfer from Zr to the neighboring matrix Al atoms exist at the Al_(3)Sc@Al_(3)(Sc,Zr)/Al interface.The Sc doping in GP−η_(p) andη_(p) suppresses the GP−η_(p)→η_(p) transformation.Modified corrosion resistance of the AA7085-Sc alloy compared with AA7085 alloy is associated with the fine grain boundary precipitates ofη_(p)hases and narrow precipitation free zone.The reasons of property changes of AA7085 alloy after Sc microalloying are explored based on the multiscale microstructural characterization.
基金supported by Young Elite Scientists Sponsorship Program by China Association for Science and Technology(No.2022QNRC001)the National Natural Science Foundation of China(No.52273053)the Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.21CGA41)。
文摘Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always struggle to balance mechanical properties and thermal insulation,resulting in their inability to meet the demands for both washing resistance and personal protection.Herein,inspired by the natural spring-like structures of cucumber tendrils,a superelastic and washable micro/nanofibrous sponge(MNFS)based on biomimetic helical fibers is directly prepared utilizing multiple-jet electrospinning technology for high-performance thermal insulation.By regulating the conductivity of polyvinylidene fluoride solution,multiple-jet ejection and multiple-stage whipping of jets are achieved,and further control of phase separation rates enables the rapid solidification of jets to form spring-like helical fibers,which are directly entangled to assemble MNFS.The resulting MNFS exhibits superelasticity that can withstand large tensile strain(200%),1000 cyclic tensile or compression deformations,and retain good resilience even in liquid nitrogen(-196℃).Furthermore,the MNFS shows efficient thermal insulation with low thermal conductivity(24.85 mW m^(-1)K^(-1)),close to the value of dry air,and remains structural stability even after cyclic washing.This work offers new possibilities for advanced fibrous sponges in transportation,environmental,and energy applications.
基金supported by the National Natural Science Foundation of China(Nos.52071053,U1704253,and 52103334).
文摘Traditional stealth materials do not fulfill the requirements of high absorption for radar waves and low emissivity for infrared waves.Furthermore,they can be detected by various technologies,considerably threatening weapon safety.Therefore,a stealth material compatible with radar and infrared was designed based on the photonic bandgap characteristics of photonic crystals.The radar stealth lay-er(bottom layer)is a composite of carbonyl iron/silicon dioxide/epoxy resin,and the infrared stealth layer(top layer)is a 1D photonic crystal with alternately and periodically stacked germanium and silicon nitride.Through composition optimization and structural adjust-ment,the effective absorption bandwidth of the compatible stealth material with a reflection loss of less than-10 dB has reached 4.95 GHz.The average infrared emissivity of the proposed design is 0.1063,indicating good stealth performance.The theoretical analysis proves that photonic crystals with this structural design can produce infrared waves within the photonic bandgap,achieving high radar wave transmittance and low infrared emissivity.Infrared stealth is achieved without affecting the absorption performance of the radar stealth layer,and the conflict between radar and infrared stealth performance is resolved.This work aims to promote the application of photonic crystals in compatible stealth materials and the development of stealth technology and to provide a design and theoretical found-ation for related experiments and research.
基金supported by National Natural Science Foundation of China(No.52103044)Double First-Class Initiative University of Science and Technology of China(KY2400000037)the Young Talent Programme(GG2400007009).
文摘Conductive elastomers combining micromechanical sensitivity,lightweight adaptability,and environmental sustainability are critically needed for advanced flexible electronics requiring precise responsiveness and long-term wearability;however,the integration of these properties remains a significant challenge.Here,we present a biomass-derived conductive elastomer featuring a rationally engineered dynamic crosslinked network integrated with a tunable microporous architecture.This structural design imparts pronounced micromechanical sensitivity,an ultralow density(~0.25 g cm^(−3)),and superior mechanical compliance for adaptive deformation.Moreover,the unique micro-spring effect derived from the porous architecture ensures exceptional stretchability(>500%elongation at break)and superior resilience,delivering immediate and stable electrical response under both subtle(<1%)and large(>200%)mechanical stimuli.Intrinsic dynamic interactions endow the elastomer with efficient room temperature self-healing and complete recyclability without compromising performance.First-principles simulations clarify the mechanisms behind micropore formation and the resulting functionality.Beyond its facile and mild fabrication process,this work establishes a scalable route toward high-performance,sustainable conductive elastomers tailored for next-generation soft electronics.
基金supported by the National Key R&D Program of China(Nos.2022YFB3504804 and 2023YFF0718303)the National Natural Science Foundation of China(Nos.51871219,52071324,52031014,and 52401255)+1 种基金Science and Technology Project of Shenyang City(No.22-101-0-27)Liaoning Institute of Science and Technology Doctoral Initiation Fund Project(No.2307B19).
文摘To realize the application of electromagnetic wave absorption(EWA)devices in humid marine environments,bifunctional EWA materials with better EWA capacities and anticorrosion properties have great exploration significance and systematic research re-quirements.By utilizing the low-cost and excellent magnetic and stable chemical characteristics of barium ferrite(BaFe_(12)O_(19))and using the high dielectric loss and excellent chemical inertia of nanocarbon clusters,a new type of nanocomposites with carbon nanoclusters en-capsulating BaFe_(12)O_(19)was designed and synthesized by combining an impregnation method and a high-temperature calcination strategy.Furthermore,Ce-Mn ions were introduced into the BaFe_(12)O_(19)lattice to improve the dielectric and magnetic properties of BaFe_(12)O_(19)cores significantly,and the energy band structure of the doped lattice and the orders of Ce replacing Fe sites were calculated.Benefiting from Ce-Mn ion doping and carbon nanocluster encapsulation,the composite material exhibited excellent dual functionality of corrosion resist-ance and EWA.When BaCe_(0.2)Mn_(0.3)Fe_(11.5)O_(19)-C(BCM-C)was calcined at 600°C,the minimum reflection loss of-20.1 dB was achieved at 14.43 GHz.The Ku band’s effective absorption bandwidth of 4.25 GHz was achieved at an absorber thickness of only 1.3 mm.The BCM-C/polydimethylsiloxane coating had excellent corrosion resistance in the simulated marine environment(3.5wt%NaCl solution).The|Z|0.01Hz value of BCM-C remained at 106Ω·cm^(2)after 12 soaking days.The successful preparation of the BaFe_(12)O_(19)composite en-capsulated with carbon nanoclusters provides new insights into the preparation of multifunctional absorbent materials and the fabrication of absorbent devices applied in humid marine environments in the future.
基金financially supported by the National Key Research and Development Program of China (No. 2023YFB3812601)the National Natural Science Foundation of China (No. 51925401)the Young Elite Scientists Sponsorship Program by CAST, China (No. 2022QNRC001)。
文摘Machine learning-assisted methods for rapid and accurate prediction of temperature field,mushy zone,and grain size were proposed for the heating−cooling combined mold(HCCM)horizontal continuous casting of C70250 alloy plates.First,finite element simulations of casting processes were carried out with various parameters to build a dataset.Subsequently,different machine learning algorithms were employed to achieve high precision in predicting temperature fields,mushy zone locations,mushy zone inclination angle,and billet grain size.Finally,the process parameters were quickly optimized using a strategy consisting of random generation,prediction,and screening,allowing the mushy zone to be controlled to the desired target.The optimized parameters are 1234℃for heating mold temperature,47 mm/min for casting speed,and 10 L/min for cooling water flow rate.The optimized mushy zone is located in the middle of the second heat insulation section and has an inclination angle of roughly 7°.
基金supported by the National Key R&D Plan of China(No.2022YFB3705603)the National Natural Science Foundation of China(No.52101046)+1 种基金the Excellent Youth Overseas Project of National Science and Natural Foundation of China,the Baowu Special Metallurgy Cooperation Limited(No.22H010101336)the Medicine-Engineering Interdisciplinary Project of Shanghai Jiao Tong University(No.YG2022QN076).
文摘Titanium(Ti)and its alloys are frequently utilized as critical components in a variety of engineering ap-plications because of their high specific strength and excellent corrosion resistance.Compared to conven-tional surface strengthening technologies,laser shock peening(LSP)has increasingly attracted attention from researchers and industries,since it significantly improves the surface strength,biocompatibility,fa-tigue resistance,and anti-corrosion ability of Ti and its alloys.Despite numerous studies that have been carried out to elucidate the effects of LSP on microstructural evolution and mechanical properties of Ti and its alloys in recent years,a comprehensive review of recent advancements in the field of Ti and its alloys subjected to LSP is still lacking.In this review,the standard LSP and the novel process designs of LSP assisted by thermal,cryogenic,electropulsing and magnetic fields are discussed and compared.Microstructural evolution,with focuses on the dislocation dynamics,deformation twinning,grain refine-ment and surface amorphization,during LSP processing of Ti alloys is reviewed.Furthermore,the en-hanced engineering performance of the L SP-processed(L SPed)Ti alloys,including surface hardness,wear resistance,fatigue life and corrosion resistance are summarized.Finally,this review concludes by present-ing an overview of the current challenges encountered in this field and offering insights into anticipated future trends.
基金National Natural Science Foundation of China(Nos.52174269,52374293)Science and Technology Innovation Program of Hunan Province,China(Nos.2024CK1009,2022RC1123)。
文摘A tunable oxidization and reduction strategy was proposed to directly regenerate spent LiFePO_(4)/C cathode materials by oxidizing excessive carbon powders with the addition of FePO_(4).Experimental results indicate that spent LiFePO_(4)/C cathode materials with good performance can be regenerated by roasting at 650℃ for 11 h with the addition ofLi_(2)CO_(3),FePO_(4),V_(2)O_(5),and glucose.V_(2)O_(5) is added to improve the cycle performance of regenerated cathode materials.Glucose is used to revitalize the carbon layers on the surface of spent LiFePO_(4)/C particles for improving their conductivity.The regenerated V-doped LiFePO_(4)/C shows an excellent electrochemical performance with the discharge specific capacity of 161.36 mA·h/g at 0.2C,under which the capacity retention is 97.85%after 100 cycles.
基金financially supported by the National Natural Science Foundation of China(52172245)the Key Scientific and Technological Innovation Project of Shandong(2023CXGC010302)the Qingdao Flexible Materials Precision Die-cutting Technology Innovation Center。
文摘In lithium-sulfur batteries(LSBs),the limited utilization of sulfur and the sluggish kinetics of redox reaction significantly hinder their electrochemical performance,especially under high rates and high sulfur loadings.Here,we propose a novel separator structure with an interlayer composed of a vermiculite nanosheet combined with Ketjen Black(VMT@KB)for LSBs,facilitating efficient adsorption and rapid catalytic conversion toward lithium polysulfides(LiPSs).The VMT@KB nanosheets with an electrical double-layer structure and electronic conductivity are obtained through a high-temperature peeling process and Li^(+)exchange treatment in LiCl solution,followed by a mechanical combination process with KB.The results demonstrate that incorporating VMT@KB as an interlayer on a conventional separator enhances the conductivity and limits the LiPSs in the cathode region.The Li-S cell with VMT@KB interlayer shows satisfactory cycle and rate performance,especially in high sulfur loading.It exhibits a remarkable initial discharge capacity of 1225 mAh g^(-1)at 0.5 C and maintains a capacity of 816 mAh g^(-1)after 500 cycles.Besides,the discharge capacity remains 462 mAh g^(-1)even at 6 C.Moreover,the cell with high sulfur loading(8.2 mg cm^(-2))enables stable cycling for 100 cycles at 0.1 C with a discharge capacity of over1000 mAh g^(-1).
基金financially supported by the National Natu-ral Science Foundation of China(Nos.52173267,21667019,and 22066017)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.22KJB430043).
文摘Metal-organic frameworks(MOFs)have been widely applied in the field of electromagnetic wave absorption(EMWA)on account of unique morphology,simple fabrication,and ultra-high porosity.Nevertheless,the facile method of protecting its structure from being destroyed remains challenging.Herein,we proposed a hydrothermal method combined with a carbonization strategy to construct the 0D/1D/2D Fe_(3)C@NC@Mo_(2)C/Fe_(3)C composites.Owing to the incorporation of polydopamine(PDA),the carbon shell formed during high-temperature carbonization effectively protected the original MIL-88A rod-like structure,and the 2D Mo_(2)C nano-sheets and 1D Fe_(3)C nanoparticles were coated on the surface of 1D Fe_(3)C nanorods.With the increase in carbonization temperature,the EMWA properties of the composites presented a trend of first increasing and then decreasing.Impressively,the composites(at 750℃)exhibited praiseworthy EMWA performances with a minimum reflection loss value of−43.70 dB at 8.00 GHz,alongside a maximum effective absorption bandwidth of 6.08 GHz(11.20-17.28 GHz).Density functional theory calculations confirmed the distinctive charge distribution resulting from the heterointerface,which is beneficial to the polarization loss and conductive loss.As a result,the outstanding EMWA performance was credited to the distinctive hierarchical structure,appropriate impedance matching,numerous heterogeneous interfaces,and magnetic loss.Moreover,Radar cross-section calculations indicated that the composites have tremendous potential for practical application.Thus,this work may pave new avenues for designing high-performance and structure-controllable absorbing materials.
基金the National Key R&D Program of China(No.2023YFE0208700)National Natural Sci-ence Foundation of China(No.92163109 and 52072095)+7 种基金Shenzhen Science and Technology Program(No.RCJC20231211090000001,GXWD20231129101105001)the National Natural Science Foundation of China(No.52205590)the Natural Science Foundation of Jiangsu Province(No.BK20220834)the Start-up Research Fund of Southeast University(No.RF1028623098)the State Key Laboratory of Robotics and Systems(HIT)(No.SKLRS-2024-KF-11)National Natural Science Foundation of China(No.52202348)Guangdong Basic and Applied Basic Research Foundation(No.2023A1515011491)Shenzhen Science and Technology Program(Nos.GXWD20220818224716001,KJZD20231023100302006).
文摘Due to the small size,active mobility,and intrinsic softness,miniature soft robots hold promising po-tentials in reaching the deep region inside living bodies otherwise inaccessible with compelling agility,adaptability and safety.Various materials and actuation strategies have been developed for creating soft robots,among which,ferromagnetic soft materials that self-actuate in response to external magnetic fields have attracted worldwide attention due to their remote controllability and excellent compatibil-ity with biological tissues.This review presents comprehensive and systematic research advancements in the design,fabrication,and applications of ferromagnetic soft materials for miniature robots,providing in-sights into their potential use in biomedical fields and beyond.The programming strategies of ferromag-netic soft materials are summarized and classified,including mold-assisted programming,3D printing-assisted programming,microassembly-assisted programming,and magnetization reprogramming.Each approach possesses unique advantages in manipulating the magnetic responsiveness of ferromagnetic soft materials to achieve outstanding actuation and deformation performances.We then discuss the biomedi-cal applications of ferromagnetic soft material-based soft robots(e.g.,minimally invasive surgery,targeted delivery,and tissue engineering),highlighting their potentials in revolutionizing biomedical technologies.This review also points out the current challenges and provides insights into future research directions,which we hope can serve as a useful reference for the development of next-generation adaptive miniature robots.
基金funded by the Joint Fund for Regional Innovation and Development of National Natural Science Foundation of China(U21A20143)the National Science Fund for Excellent Young Scholars(52322607)the Excellent Youth Foundation of Heilongjiang Scientific Committee(YQ2022E028)。
文摘Improving the volumetric energy density of supercapacitors is essential for practical applications,which highly relies on the dense storage of ions in carbon-based electrodes.The functional units of carbon-based electrode exhibit multi-scale structural characteristics including macroscopic electrode morphologies,mesoscopic microcrystals and pores,and microscopic defects and dopants in the carbon basal plane.Therefore,the ordered combination of multi-scale structures of carbon electrode is crucial for achieving dense energy storage and high volumetric performance by leveraging the functions of various scale structu re.Considering that previous reviews have focused more on the discussion of specific scale structu re of carbon electrodes,this review takes a multi-scale perspective in which recent progresses regarding the structureperformance relationship,underlying mechanism and directional design of carbon-based multi-scale structures including carbon morphology,pore structure,carbon basal plane micro-environment and electrode technology on dense energy storage and volumetric property of supercapacitors are systematically discussed.We analyzed in detail the effects of the morphology,pore,and micro-environment of carbon electrode materials on ion dense storage,summarized the specific effects of different scale structures on volumetric property and recent research progress,and proposed the mutual influence and trade-off relationship between various scale structures.In addition,the challenges and outlooks for improving the dense storage and volumetric performance of carbon-based supercapacitors are analyzed,which can provide feasible technical reference and guidance for the design and manufacture of dense carbon-based electrode materials.
