Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation ac...Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation activity were studied.Several different carbon materi-als were produced from them by oxida-tion in air(350℃,300 mL/min)fol-lowed by carbonization(1000℃ in Ar),and the effect of the cross-linked structure on their structure and sodium storage properties was investigated.The results showed that the two pitch fractions were obviously different after the air oxidation.The TS fraction with a low degree of condensation and abundant side chains had a stronger oxidation activity and thus introduced more cross-linked oxygen-containing functional groups C(O)―O which prevented carbon layer rearrangement during the carbonization.As a result,a disordered hard carbon with more defects was formed,which improved the electrochemical performance.Therefore,the carbon materials derived from TS(O-TS-1000)had an obvious disordered structure and a larger layer spacing,giving them better sodium storage perform-ance than those derived from the TI-PS fraction(O-TI-PS-1000).The specific capacity of O-TS-1000 was about 250 mAh/g at 20 mA/g,which was 1.67 times higher than that of O-TI-PS-1000(150 mAh/g).展开更多
Sodium-ion batteries (SIBs) with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ions.Currently,organic electrode materials ...Sodium-ion batteries (SIBs) with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ions.Currently,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials(>1 V).Organic electrodes with low redox potential that can be used as anode are rare.Herein,a novel organic anode material (tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na_(4)TDC) has been developed with low redox potential (<0.7 V) and excellent cyclic stability.Its three-sodium storage mechanism was demonstrated with various in-situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per cycle.Moreover,the Na_(4)TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg cm^(-2).By pairing with a thick Na_(3)V_(2)(PO_(4))_(3)cathode (20.6 mg cm^(-2)),the as-fabricated full cell exhibited high operating voltage (2.8 V),excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na_(4)TDC anode material for SIBs.展开更多
High-performance graphite materials have important roles in aerospace and nuclear reactor technologies because of their outstanding chemical stability and high-temperature performance.Their traditional production meth...High-performance graphite materials have important roles in aerospace and nuclear reactor technologies because of their outstanding chemical stability and high-temperature performance.Their traditional production method relies on repeated impregnation-carbonization and graphitization,and is plagued by lengthy preparation cycles and high energy consumption.Phase transition-assisted self-pressurized selfsintering technology can rapidly produce high-strength graphite materials,but the fracture strain of the graphite materials produced is poor.To solve this problem,this study used a two-step sintering method to uniformly introduce micro-nano pores into natural graphite-based bulk graphite,achieving improved fracture strain of the samples without reducing their density and mechanical properties.Using natural graphite powder,micron-diamond,and nano-diamond as raw materials,and by precisely controlling the staged pressure release process,the degree of diamond phase transition expansion was effectively regulated.The strain-to-failure of the graphite samples reached 1.2%,a 35%increase compared to samples produced by fullpressure sintering.Meanwhile,their flexural strength exceeded 110 MPa,and their density was over 1.9 g/cm^(3).The process therefore produced both a high strength and a high fracture strain.The interface evolution and toughening mechanism during the two-step sintering process were investigated.It is believed that the micro-nano pores formed have two roles:as stress concentrators they induce yielding by shear and as multi-crack propagation paths they significantly lengthen the crack propagation path.The two-step sintering phase transition strategy introduces pores and provides a new approach for increasing the fracture strain of brittle materials.展开更多
Based on simplified calculations of one-dimensional wave systems,loading pressure platform curves of Al-Cu gradient materials(GMs)impactor were designed.The Al-Cu GMs were prepared using tape-pressing sintering,and th...Based on simplified calculations of one-dimensional wave systems,loading pressure platform curves of Al-Cu gradient materials(GMs)impactor were designed.The Al-Cu GMs were prepared using tape-pressing sintering,and their acoustic properties were characterized to match the design path.The parallelism of the Al-Cu GM was confirmed using a three-dimensional surface profilometry machine.A one-stage light-gas gun was used to launch the Al-Cu GM,impacting an Al-LiF target at a velocity of 400 m/s.The results of the experimental strain rate demonstrate that the Al-Cu GMs can realize the precise control of the strain rate within the range of 10^(4)‒10^(5)/s in the high-speed impact experiments.展开更多
The ring has been a romantic fascination throughout the ages,embodying not only beauty and order but also harboring numerous undisclosed properties awaiting discovery.In the realm of supramolecular chemistry,macrocycl...The ring has been a romantic fascination throughout the ages,embodying not only beauty and order but also harboring numerous undisclosed properties awaiting discovery.In the realm of supramolecular chemistry,macrocycles,with a cyclic structure and a central cavity like a doughnut,captivate the attention of scientists[1].In 1967,Pedersen's groundbreaking revelation that alkali metal ions could"fall into"the cavities of a cyclic ether named crown ether,even in organic solvents,unveiled a novel universe of macrocycle chemistry.Since then,numerous macrocyclic structures in nature have been discovered,isolated,and scrutinized.Drawing inspiration from nature,chemists endeavor to explore the vast potential of macrocyclic compounds by designing and synthesizing artificial macrocycles with diverse structural features and recognition properties.展开更多
This study begins by exploring the typical practical applications of phase‐change materials(PCMs)in various industries,highlighting their importance in energy storage,temperature regulation,and thermal management.It ...This study begins by exploring the typical practical applications of phase‐change materials(PCMs)in various industries,highlighting their importance in energy storage,temperature regulation,and thermal management.It then emphasizes the necessity of flame‐retardant functionalization tailored to the specific application scenarios of PCMs,especially considering their use in safety‐critical environments such as electronics,automotive,and construction.The classic characterization methods for assessing the flame‐retardant properties of PCM are introduced in detail,including the limiting oxygen index,the vertical burning test,and the cone calorimeter,which are widely recognized standards in material safety testing.Additionally,newly developed methods for evaluating combustion safety are discussed,such as direct combustion tests,candle combustion experiments,and back temperature response,which offer a more comprehensive understanding of the material's fire resistance.Following this,this study provides a thorough summary and categorization of the flame‐retardant strategies used in PCMs,divided into four main approaches:(1)incorporation of external flame retardants,(2)use of flame‐retardant microcapsules,(3)development of flame‐retardant support materials,and(4)creation of intrinsic flame‐retardant PCMs.Each strategy is critically analyzed in terms of effectiveness,applicability,and potential challenges.Lastly,the conclusion provides an overview of the current state of flame‐retardant PCMs,offering insights into future development directions,including the pursuit of more sustainable and efficient flame‐retardant solutions,as well as prospects for their broader adoption in various industries.展开更多
Photothermal energy conversion represents a cornerstone process in the renewable energy technologies domain,enabling the capture of solar irradiance and its subsequent transformation into thermal energy.This mechanism...Photothermal energy conversion represents a cornerstone process in the renewable energy technologies domain,enabling the capture of solar irradiance and its subsequent transformation into thermal energy.This mechanism is paramount across many applications,facilitating the exploitation of solar energy for different purposes.The photothermal conversion efficiency and applications are fundamentally contingent upon the characteristics and performance of the materials employed.Consequently,deploying high-caliber materials is essential for optimizing energy capture and utilization.Within this context,photothermal nanomaterials have emerged as pivotal components in various applications,ranging from catalysis and sterilization to medical therapy,desalination,and electric power generation via the photothermal conversion effect.This review endeavors to encapsulate the current research landscape,delineating both the developmental trajectories and application horizons of photothermal conversion materials.It aims to furnish a detailed exposition of the mechanisms underlying photothermal conversion across various materials,shedding light on the principles guiding the design of photothermal nanomaterials.Furthermore,addressing the prevailing challenges and outlooks within the field elucidates potential avenues for future research and identifying priority areas.This review aspires to enrich the understanding of photothermal materials within the framework of energy conversion,offering novel insights and fostering a more profound comprehension of their role and potential in harnessing solar energy.展开更多
Heat dissipation and thermal switches are vital for adaptive cooling and extending the lifespan of electronic devices and batteries. In this work, we conducted high-throughput investigations on the thermal transport o...Heat dissipation and thermal switches are vital for adaptive cooling and extending the lifespan of electronic devices and batteries. In this work, we conducted high-throughput investigations on the thermal transport of 24 experimentally realized two-dimensional(2D) materials and their potential as thermal switches, leveraging machine-learning-assisted strain engineering and phonon transport simulations. We identified several highperformance thermal switches with ratios exceeding 2, with germanene(Ge) achieving an ultrahigh ratio of up to9.64 within the reversible deformation range. The underlying mechanism is strain-induced bond softening, which sensitively affects anharmonicity represented by three-and four-phonon scattering. The widespread occurrence of four-phonon scattering was confirmed in the thermal transport of 2D materials. Opposite switching trends were discovered, with 2D transition metal dichalcogenide materials showing negative responses to tensile strain while buckled 2D elemental materials showed positive responses. We further proposed a screening descriptor based on strain-induced changes in the Gr¨uneisen parameter for efficiently identifying new high-performance thermal switch materials. This work establishes a paradigm for thermal energy control in 2D materials through strain engineering, which may be experimentally realized in the future via bending, substrate mismatch, and related approaches, thereby laying a robust foundation for further developments and applications.展开更多
To improve the slow kinetics and poor mechanical strength of aqueous silver peroxide−aluminum(AgO−Al)battery cathode materials,the effects of different binders including polytetrafluoroethylene(PTFE)and polyvinylpyrro...To improve the slow kinetics and poor mechanical strength of aqueous silver peroxide−aluminum(AgO−Al)battery cathode materials,the effects of different binders including polytetrafluoroethylene(PTFE)and polyvinylpyrrolidone(PVP)on the AgO cathode material were investigated.The samples were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),cyclic voltammetry(CV),electrochemical impedance spectrum(EIS),and galvanostatic discharge.In contrast to the pure AgO and AgO−PTFE electrodes,the results demonstrated that the PVP effectively bound the electrode materials together.The prepared AgO−PVP as the cathode material of AgO−Al batteries could improve the battery capacity,exhibiting a high specific capacity(389.95 mA·h/g at 500 mA/cm^(2)),a high operating voltage(1.75 V at 500 mA/cm^(2)),a maximum energy density(665.65 W·h/kg),and a maximum power density(5236 W/kg).Furthermore,the electrochemical mechanism of the AgO−PVP cathode material was examined,revealing that the electrode exhibited rapid ion diffusion and effective interfacial ion/electron transport.展开更多
Professor Kazunari Domen at the Shinshu University and the University of Tokyo has pioneered materials and techniques for solar-driven water splitting using photocatalysts,a promising technology for contributing to th...Professor Kazunari Domen at the Shinshu University and the University of Tokyo has pioneered materials and techniques for solar-driven water splitting using photocatalysts,a promising technology for contributing to the construction of a sustainable and carbon-neutral society.In this paper,we summarize his groundbreaking contributions to photocatalytic water splitting and,more broadly,photocatalytic research.We highlight various novel functional photocatalytic materials,including oxides,(oxy)nitrides,and oxysulfides,along with innovative techniques such as cocatalyst engineering and Z-scheme system construction developed by the Domen Group.His team has also pioneered readily accessible and cost-effective photo(electro)chemical device fabrication methods,such as the particle-transfer method and thin-film-transfer method.Furthermore,their research has made significant contributions to understanding the(photo)catalytic mechanisms using advanced characterization techniques.Together with his research team,Professor Domen has set many milestones in the field of photocatalytic overall water splitting,notably demonstrating the first scalable and stable 100 m^(2)solar H_(2)production system using only water and sunlight.His work has revealed the potential for practical solar H2 production from water and sunlight,and highlighted the application of fundamental principles,combined with chemical and materials science tools,to design effective photocatalytic systems.Through this review,we focus on his research and the foundational design principles that can inspire the development of efficient photocatalytic systems for water splitting and solar fuel production.By building on his contributions,we anticipate a significant impact on addressing major global energy challenges.展开更多
Plant cell wall(CW)-like soft materials,referred to as artificial CWs,are composites of assembled polymers containing micro-/nanoparticles or fibers/fibrils that are designed to mimic the composition,structure,and mec...Plant cell wall(CW)-like soft materials,referred to as artificial CWs,are composites of assembled polymers containing micro-/nanoparticles or fibers/fibrils that are designed to mimic the composition,structure,and mechanics of plant CWs.CW-like materials have recently emerged to test hypotheses pertaining to the intricate structure–property relationships of native plant CWs or to fabricate functional materials.Here,research on plant CWs and CW-like materials is reviewed by distilling key studies on biomimetic composites primarily composed of plant polysaccharides,including cellulose,pectin,and hemicellulose,as well as organic polymers like lignin.Micro-and nanofabrication of plant CW-like composites,characterization techniques,and in silico studies are reviewed,with a brief overview of current and potential applications.Micro-/nanofabrication approaches include bacterial growth and impregnation,layer-by-layer assembly,film casting,3-dimensional templating microcapsules,and particle coating.Various characterization techniques are necessary for the comprehensive mechanical,chemical,morphological,and structural analyses of plant CWs and CW-like materials.CW-like materials demonstrate versatility in real-life applications,including biomass conversion,pulp and paper,food science,construction,catalysis,and reaction engineering.This review seeks to facilitate the rational design and thorough characterization of plant CW-mimetic materials,with the goal of advancing the development of innovative soft materials and elucidating the complex structure–property relationships inherent in native CWs.展开更多
In recent years,superhard coatings have emerged as a focal point in metal material research due to their innovative design strategies and exceptional mechanical properties.They are widely utilized in industries such a...In recent years,superhard coatings have emerged as a focal point in metal material research due to their innovative design strategies and exceptional mechanical properties.They are widely utilized in industries such as shielding,oil extraction,and coal mining.However,in practical applications,tools often suffer from wear,fractures,plastic deformation,and other types of failure,directly impacting machining efficiency,costs,and product quality.To mitigate these challenges,the selection of appropriate tool materials and preparation methods is critical to ensure sustained production efficiency.Therefore,it is essential to identify and develop coating materials with superior performance.Recent advancements in superhard coatings are reviewed comprehensively;preparation methods are discussed for superhard tools;diamond coatings,diamond-like carbon coatings,cubic boron nitride coatings and graphite carbon nitride coatings are examined specifically.It analyzes their microstructures,phase transformation processes,mechanical properties,and formation mechanisms,while also evaluating properties such as wear resistance,corrosion resistance,and high hardness.The applicability of existing theoretical models is verified and new frameworks for future superhard coating designs are proposed.Moreover,the current research limitations in tool coatings are identified and directions for future research and development are proposed.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
Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and v...Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials.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
The unique crystallographic lamellar microstructure(CLM) Ni-based superalloys fabricated by laser powder bed fusion(LPBF) exhibits excellent tensile properties.This study aims to investigate CLM's high-temperature...The unique crystallographic lamellar microstructure(CLM) Ni-based superalloys fabricated by laser powder bed fusion(LPBF) exhibits excellent tensile properties.This study aims to investigate CLM's high-temperature stress rupture behavior and use these findings to improve the additive manufacturing process.The result shows that the high temperature-induced intergranular fracture in <110> grain region is responsible for stress rupture failure under both conditions of 760 ℃/780 MPa and 980 ℃/260 MPa.Among them,the sub-grain boundary fracture occurs only under high temperature and low stress,980 ℃/260 MPa.Due to the severe intergranular fracture induced by stray grains,the stress rupture life is very low under both conditions.According to the finite element simulation,the formation of stray grains stems from the unstable heat flow within the melt pool during the process.In addition,the shorter stress rupture lifetime does not excite a more pronounced dislocation network around the γ′ phase.However,the deformation twins can still be activated inside the <110> grains,so it has excellent plasticity under both test conditions.Finally,this work indicates that the future optimization of CLM by LPBF should focus on eliminating of high-angle grain boundaries in <110> grains.展开更多
Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro...Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts.展开更多
The high cost and low efficiency of fatigue tests are bottleneck problem for the anti-fatigue design of metallic materials.For this problem,a theoretical fatigue model is proposed in this study,the possible applicatio...The high cost and low efficiency of fatigue tests are bottleneck problem for the anti-fatigue design of metallic materials.For this problem,a theoretical fatigue model is proposed in this study,the possible applications have also been discussed.Specific results would be introduced in two serial papers,in which the first paper focuses on the model building and the applications on fatigue strength prediction;the second paper put emphasis on the influencing factors of the model parameters and the applications on fatigue strength improvement.In this first paper,a theoretical model is proposed considering both the strength and plastic restrictions of fatigue strength.As the model builds up a brief relationship among yield strength(Y),tensile strength(T)and fatigue strength(F),it is named as the Y-T-F model.Through the verification with fatigue strength data covering various kinds of metallic materials and loading conditions,this Y-T-F model exhibits both generality and accuracy.With the Y-T-F model,the efficient fatigue strength prediction could be conducted by brief linear fitting and calculation,just through yield strength,tensile strength and several known fatigue strength data.Moreover,through its deduced Y-F model,the analytical formula of fatigue strength continuously changing with materials strengthening can be obtained,as well as the maximum value of fatigue strength and corresponding critical yield strength.In summary,the Y-T-F model would be useful for reducing the fatigue tests,thus providing new possibilities on the efficient anti-fatigue design and selection of metallic materials.展开更多
The isolation of the first two-dimensional material, graphene-a monolayer of carbon atoms arranged in a hexagonal lattice-opened new exciting opportunities in the field of condensed matter physics and materials. Its i...The isolation of the first two-dimensional material, graphene-a monolayer of carbon atoms arranged in a hexagonal lattice-opened new exciting opportunities in the field of condensed matter physics and materials. Its isolation and subsequent studies demonstrated that it was possible to obtain sheets of atomically thin crystals and that these were stable, and they also began to show its outstanding properties, thus opening the door to a whole new family of materials, known as two-dimensional materials or 2D materials. The great interest in different 2D materials is motivated by the variety of properties they show, being candidates for numerous applications.Additionally, the combination of 2D crystals allows the assembly of composite, on-demand materials, known as van der Waals heterostructures, which take advantage of the properties of those materials to create functionalities that otherwise would not be accessible. For example, the combination of 2D materials, which can be done with high precision, is opening up opportunities for the study of new challenges in fundamental physics and novel applications. Here we review the latest fundamental discoveries in the area of 2D materials and offer a perspective on the future of the field.展开更多
High flammability of polymers has become a major issue which has restricted its applications.Recently,highly crystalline materials and metal–organic frameworks(MOFs),which consisted of metal ions and organic linkers,...High flammability of polymers has become a major issue which has restricted its applications.Recently,highly crystalline materials and metal–organic frameworks(MOFs),which consisted of metal ions and organic linkers,have been intensively employed as novel fire retardants(FRs)for a variety of polymers(MOF/polymer).The MOFs possessed abundant transition metal species,fire-retardant elements and potential carbon source accompanied with the facile tuning of the structure and property,making MOF,its derivatives and MOF hybrids promising for fire retardancy research.The recent progress and strategies to prepare MOF-based FRs are emphasized and summarized.The fire retardancy mechanisms of MOF/polymer composites are explained,which may guide the future design for efficient MOF-based FRs.Finally,the challenges and prospects related to different MOFbased FRs are also discussed and aim to provide a fast and holistic overview,which is beneficial for researchers to quickly get up to speed with the latest development in this field.展开更多
文摘Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation activity were studied.Several different carbon materi-als were produced from them by oxida-tion in air(350℃,300 mL/min)fol-lowed by carbonization(1000℃ in Ar),and the effect of the cross-linked structure on their structure and sodium storage properties was investigated.The results showed that the two pitch fractions were obviously different after the air oxidation.The TS fraction with a low degree of condensation and abundant side chains had a stronger oxidation activity and thus introduced more cross-linked oxygen-containing functional groups C(O)―O which prevented carbon layer rearrangement during the carbonization.As a result,a disordered hard carbon with more defects was formed,which improved the electrochemical performance.Therefore,the carbon materials derived from TS(O-TS-1000)had an obvious disordered structure and a larger layer spacing,giving them better sodium storage perform-ance than those derived from the TI-PS fraction(O-TI-PS-1000).The specific capacity of O-TS-1000 was about 250 mAh/g at 20 mA/g,which was 1.67 times higher than that of O-TI-PS-1000(150 mAh/g).
基金National Key Research and Development Program of China (2022YFB2402200)National Natural Science Foundation of China (22225201,22379028)+2 种基金Fundamental Research Funds for the Central Universities (20720220010)Shanghai Pilot Program for Basic Research–Fudan University 21TQ1400100 (21TQ009)Key Basic Research Program of Science and Technology Commission of Shanghai Municipality (23520750400)。
文摘Sodium-ion batteries (SIBs) with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ions.Currently,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials(>1 V).Organic electrodes with low redox potential that can be used as anode are rare.Herein,a novel organic anode material (tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na_(4)TDC) has been developed with low redox potential (<0.7 V) and excellent cyclic stability.Its three-sodium storage mechanism was demonstrated with various in-situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per cycle.Moreover,the Na_(4)TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg cm^(-2).By pairing with a thick Na_(3)V_(2)(PO_(4))_(3)cathode (20.6 mg cm^(-2)),the as-fabricated full cell exhibited high operating voltage (2.8 V),excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na_(4)TDC anode material for SIBs.
基金Natural Science Foundation of Shanghai(24ZR1400800)he Natural Science Foundation of China(U23A20685,52073058,91963204)+1 种基金the National Key R&D Program of China(2021YFB3701400)Shanghai Sailing Program(23YF1400200)。
文摘High-performance graphite materials have important roles in aerospace and nuclear reactor technologies because of their outstanding chemical stability and high-temperature performance.Their traditional production method relies on repeated impregnation-carbonization and graphitization,and is plagued by lengthy preparation cycles and high energy consumption.Phase transition-assisted self-pressurized selfsintering technology can rapidly produce high-strength graphite materials,but the fracture strain of the graphite materials produced is poor.To solve this problem,this study used a two-step sintering method to uniformly introduce micro-nano pores into natural graphite-based bulk graphite,achieving improved fracture strain of the samples without reducing their density and mechanical properties.Using natural graphite powder,micron-diamond,and nano-diamond as raw materials,and by precisely controlling the staged pressure release process,the degree of diamond phase transition expansion was effectively regulated.The strain-to-failure of the graphite samples reached 1.2%,a 35%increase compared to samples produced by fullpressure sintering.Meanwhile,their flexural strength exceeded 110 MPa,and their density was over 1.9 g/cm^(3).The process therefore produced both a high strength and a high fracture strain.The interface evolution and toughening mechanism during the two-step sintering process were investigated.It is believed that the micro-nano pores formed have two roles:as stress concentrators they induce yielding by shear and as multi-crack propagation paths they significantly lengthen the crack propagation path.The two-step sintering phase transition strategy introduces pores and provides a new approach for increasing the fracture strain of brittle materials.
基金Natural Science Foundation of Hubei Province(2024AFB432)National Natural Science Foundation of China(52171045,12302436,52302095)Research Fund of Jianghan University(2023JCYJ05)。
文摘Based on simplified calculations of one-dimensional wave systems,loading pressure platform curves of Al-Cu gradient materials(GMs)impactor were designed.The Al-Cu GMs were prepared using tape-pressing sintering,and their acoustic properties were characterized to match the design path.The parallelism of the Al-Cu GM was confirmed using a three-dimensional surface profilometry machine.A one-stage light-gas gun was used to launch the Al-Cu GM,impacting an Al-LiF target at a velocity of 400 m/s.The results of the experimental strain rate demonstrate that the Al-Cu GMs can realize the precise control of the strain rate within the range of 10^(4)‒10^(5)/s in the high-speed impact experiments.
文摘The ring has been a romantic fascination throughout the ages,embodying not only beauty and order but also harboring numerous undisclosed properties awaiting discovery.In the realm of supramolecular chemistry,macrocycles,with a cyclic structure and a central cavity like a doughnut,captivate the attention of scientists[1].In 1967,Pedersen's groundbreaking revelation that alkali metal ions could"fall into"the cavities of a cyclic ether named crown ether,even in organic solvents,unveiled a novel universe of macrocycle chemistry.Since then,numerous macrocyclic structures in nature have been discovered,isolated,and scrutinized.Drawing inspiration from nature,chemists endeavor to explore the vast potential of macrocyclic compounds by designing and synthesizing artificial macrocycles with diverse structural features and recognition properties.
基金supported by NEWSAFE(No.:PID2022‐143324NA‐I00)Projects funded by MICIU(Ministerio de Ciencia,Innovación y Universidades)/AEI(Agencia Estatal de Investigación)/10.13039/501100011033 and,as appropriate,by“ERDF/EU”Ramón y Cajal Fellowship(No.:RYC2023‐045023‐I)funded by MICIU,and,as appropriate,“ESF Investing in your future.”This study was also partially supported by INC‐UDIT‐2025‐PRO21 and INC‐UDIT‐2025‐JCR24.
文摘This study begins by exploring the typical practical applications of phase‐change materials(PCMs)in various industries,highlighting their importance in energy storage,temperature regulation,and thermal management.It then emphasizes the necessity of flame‐retardant functionalization tailored to the specific application scenarios of PCMs,especially considering their use in safety‐critical environments such as electronics,automotive,and construction.The classic characterization methods for assessing the flame‐retardant properties of PCM are introduced in detail,including the limiting oxygen index,the vertical burning test,and the cone calorimeter,which are widely recognized standards in material safety testing.Additionally,newly developed methods for evaluating combustion safety are discussed,such as direct combustion tests,candle combustion experiments,and back temperature response,which offer a more comprehensive understanding of the material's fire resistance.Following this,this study provides a thorough summary and categorization of the flame‐retardant strategies used in PCMs,divided into four main approaches:(1)incorporation of external flame retardants,(2)use of flame‐retardant microcapsules,(3)development of flame‐retardant support materials,and(4)creation of intrinsic flame‐retardant PCMs.Each strategy is critically analyzed in terms of effectiveness,applicability,and potential challenges.Lastly,the conclusion provides an overview of the current state of flame‐retardant PCMs,offering insights into future development directions,including the pursuit of more sustainable and efficient flame‐retardant solutions,as well as prospects for their broader adoption in various industries.
基金support from the National Natural Science Foundation of China(22072170,U23A20125)the Zhejiang Provincial Key Research and Development Program(2021C03170).
文摘Photothermal energy conversion represents a cornerstone process in the renewable energy technologies domain,enabling the capture of solar irradiance and its subsequent transformation into thermal energy.This mechanism is paramount across many applications,facilitating the exploitation of solar energy for different purposes.The photothermal conversion efficiency and applications are fundamentally contingent upon the characteristics and performance of the materials employed.Consequently,deploying high-caliber materials is essential for optimizing energy capture and utilization.Within this context,photothermal nanomaterials have emerged as pivotal components in various applications,ranging from catalysis and sterilization to medical therapy,desalination,and electric power generation via the photothermal conversion effect.This review endeavors to encapsulate the current research landscape,delineating both the developmental trajectories and application horizons of photothermal conversion materials.It aims to furnish a detailed exposition of the mechanisms underlying photothermal conversion across various materials,shedding light on the principles guiding the design of photothermal nanomaterials.Furthermore,addressing the prevailing challenges and outlooks within the field elucidates potential avenues for future research and identifying priority areas.This review aspires to enrich the understanding of photothermal materials within the framework of energy conversion,offering novel insights and fostering a more profound comprehension of their role and potential in harnessing solar energy.
基金supported bythe Science and Technology Commission of Shanghai Municipality (Grant No.24CL2901702)The numerical calculations were performed at the Supercomputer Center (Project No.2024-Cb-0042)Institute for Solid State Physics,the University of Tokyo。
文摘Heat dissipation and thermal switches are vital for adaptive cooling and extending the lifespan of electronic devices and batteries. In this work, we conducted high-throughput investigations on the thermal transport of 24 experimentally realized two-dimensional(2D) materials and their potential as thermal switches, leveraging machine-learning-assisted strain engineering and phonon transport simulations. We identified several highperformance thermal switches with ratios exceeding 2, with germanene(Ge) achieving an ultrahigh ratio of up to9.64 within the reversible deformation range. The underlying mechanism is strain-induced bond softening, which sensitively affects anharmonicity represented by three-and four-phonon scattering. The widespread occurrence of four-phonon scattering was confirmed in the thermal transport of 2D materials. Opposite switching trends were discovered, with 2D transition metal dichalcogenide materials showing negative responses to tensile strain while buckled 2D elemental materials showed positive responses. We further proposed a screening descriptor based on strain-induced changes in the Gr¨uneisen parameter for efficiently identifying new high-performance thermal switch materials. This work establishes a paradigm for thermal energy control in 2D materials through strain engineering, which may be experimentally realized in the future via bending, substrate mismatch, and related approaches, thereby laying a robust foundation for further developments and applications.
基金supported by the Fundamental Research Funds for the Central Universities of Central South University,China(No.2022XQLH046)the Technical Area Fund of Foundation Strengthening,China(No.2022-JCJQ-ZD-174-00-20)National Defense Basic Scientific Research Projects,China,and Central South University−Zijin Mining Technical Cooperation Development Project,China.
文摘To improve the slow kinetics and poor mechanical strength of aqueous silver peroxide−aluminum(AgO−Al)battery cathode materials,the effects of different binders including polytetrafluoroethylene(PTFE)and polyvinylpyrrolidone(PVP)on the AgO cathode material were investigated.The samples were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),cyclic voltammetry(CV),electrochemical impedance spectrum(EIS),and galvanostatic discharge.In contrast to the pure AgO and AgO−PTFE electrodes,the results demonstrated that the PVP effectively bound the electrode materials together.The prepared AgO−PVP as the cathode material of AgO−Al batteries could improve the battery capacity,exhibiting a high specific capacity(389.95 mA·h/g at 500 mA/cm^(2)),a high operating voltage(1.75 V at 500 mA/cm^(2)),a maximum energy density(665.65 W·h/kg),and a maximum power density(5236 W/kg).Furthermore,the electrochemical mechanism of the AgO−PVP cathode material was examined,revealing that the electrode exhibited rapid ion diffusion and effective interfacial ion/electron transport.
基金supported by the Artificial Photosynthesis Project of the New Energy and Industrial Technology Development Organization(NEDO),the JST Fusion Oriented Research for disruptive Science and Technology Program(JPMJFR213D)JSPS KAKENHI(JP24K17774)Domen for his guidance during their PhD studies at the University of Tokyo,as well as for his ongoing support,encouragement,and mentorship.
文摘Professor Kazunari Domen at the Shinshu University and the University of Tokyo has pioneered materials and techniques for solar-driven water splitting using photocatalysts,a promising technology for contributing to the construction of a sustainable and carbon-neutral society.In this paper,we summarize his groundbreaking contributions to photocatalytic water splitting and,more broadly,photocatalytic research.We highlight various novel functional photocatalytic materials,including oxides,(oxy)nitrides,and oxysulfides,along with innovative techniques such as cocatalyst engineering and Z-scheme system construction developed by the Domen Group.His team has also pioneered readily accessible and cost-effective photo(electro)chemical device fabrication methods,such as the particle-transfer method and thin-film-transfer method.Furthermore,their research has made significant contributions to understanding the(photo)catalytic mechanisms using advanced characterization techniques.Together with his research team,Professor Domen has set many milestones in the field of photocatalytic overall water splitting,notably demonstrating the first scalable and stable 100 m^(2)solar H_(2)production system using only water and sunlight.His work has revealed the potential for practical solar H2 production from water and sunlight,and highlighted the application of fundamental principles,combined with chemical and materials science tools,to design effective photocatalytic systems.Through this review,we focus on his research and the foundational design principles that can inspire the development of efficient photocatalytic systems for water splitting and solar fuel production.By building on his contributions,we anticipate a significant impact on addressing major global energy challenges.
基金supported as part of The Center for LignoCellulose Structure and Formation,an Energy Frontier Research Center funded by the U.S.Department of Energy,Office of Science,Basic Energy Sciences under Award#DE-SC0001090support from the Huck Institutes of the Life Sciences at Penn State University through the Patricia and Stephen Benkovic Research Initiativesupported by the Center for Engineering Mechano Biology(CEMB),an NSF Science and Technology Center,under grant agreement CMMI:15-48571。
文摘Plant cell wall(CW)-like soft materials,referred to as artificial CWs,are composites of assembled polymers containing micro-/nanoparticles or fibers/fibrils that are designed to mimic the composition,structure,and mechanics of plant CWs.CW-like materials have recently emerged to test hypotheses pertaining to the intricate structure–property relationships of native plant CWs or to fabricate functional materials.Here,research on plant CWs and CW-like materials is reviewed by distilling key studies on biomimetic composites primarily composed of plant polysaccharides,including cellulose,pectin,and hemicellulose,as well as organic polymers like lignin.Micro-and nanofabrication of plant CW-like composites,characterization techniques,and in silico studies are reviewed,with a brief overview of current and potential applications.Micro-/nanofabrication approaches include bacterial growth and impregnation,layer-by-layer assembly,film casting,3-dimensional templating microcapsules,and particle coating.Various characterization techniques are necessary for the comprehensive mechanical,chemical,morphological,and structural analyses of plant CWs and CW-like materials.CW-like materials demonstrate versatility in real-life applications,including biomass conversion,pulp and paper,food science,construction,catalysis,and reaction engineering.This review seeks to facilitate the rational design and thorough characterization of plant CW-mimetic materials,with the goal of advancing the development of innovative soft materials and elucidating the complex structure–property relationships inherent in native CWs.
基金financially supported by the National Natural Science Foundation of China(No.52475347)the National Program of Foreign Experts of China(No.G2023026003L)+3 种基金the High-end Foreign Experts Introduction Project of Henan Province,China(No.HNGD2025026)Project supported by the Program for the Top Young Talents of Henan Province,China,Project(No.242102521057)sponsored by the International Science and Technology Cooperation Project of Henan Province,China,and projects supported by China Postdoctoral Foundation(No.2023M740475)Henan Provincial Science and Technology R&D Joint Fund(Industry)(No.225101610002).
文摘In recent years,superhard coatings have emerged as a focal point in metal material research due to their innovative design strategies and exceptional mechanical properties.They are widely utilized in industries such as shielding,oil extraction,and coal mining.However,in practical applications,tools often suffer from wear,fractures,plastic deformation,and other types of failure,directly impacting machining efficiency,costs,and product quality.To mitigate these challenges,the selection of appropriate tool materials and preparation methods is critical to ensure sustained production efficiency.Therefore,it is essential to identify and develop coating materials with superior performance.Recent advancements in superhard coatings are reviewed comprehensively;preparation methods are discussed for superhard tools;diamond coatings,diamond-like carbon coatings,cubic boron nitride coatings and graphite carbon nitride coatings are examined specifically.It analyzes their microstructures,phase transformation processes,mechanical properties,and formation mechanisms,while also evaluating properties such as wear resistance,corrosion resistance,and high hardness.The applicability of existing theoretical models is verified and new frameworks for future superhard coating designs are proposed.Moreover,the current research limitations in tool coatings are identified and directions for future research and development are proposed.
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supported by the Major Project for the Integration of ScienceEducation and Industry (Grant No.2025ZDZX02)。
文摘Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials.
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the financial support by the Project of Taihang Laboratory (No. A3023)Science Center for Gas Turbine Project (Grant No. P2022-CIV-002-001)。
文摘The unique crystallographic lamellar microstructure(CLM) Ni-based superalloys fabricated by laser powder bed fusion(LPBF) exhibits excellent tensile properties.This study aims to investigate CLM's high-temperature stress rupture behavior and use these findings to improve the additive manufacturing process.The result shows that the high temperature-induced intergranular fracture in <110> grain region is responsible for stress rupture failure under both conditions of 760 ℃/780 MPa and 980 ℃/260 MPa.Among them,the sub-grain boundary fracture occurs only under high temperature and low stress,980 ℃/260 MPa.Due to the severe intergranular fracture induced by stray grains,the stress rupture life is very low under both conditions.According to the finite element simulation,the formation of stray grains stems from the unstable heat flow within the melt pool during the process.In addition,the shorter stress rupture lifetime does not excite a more pronounced dislocation network around the γ′ phase.However,the deformation twins can still be activated inside the <110> grains,so it has excellent plasticity under both test conditions.Finally,this work indicates that the future optimization of CLM by LPBF should focus on eliminating of high-angle grain boundaries in <110> grains.
基金the financial support from the National Natural Science Foundation of China(52172110,52472231,52311530113)Shanghai"Science and Technology Innovation Action Plan"intergovernmental international science and technology cooperation project(23520710600)+1 种基金Science and Technology Commission of Shanghai Municipality(22DZ1205600)the Central Guidance on Science and Technology Development Fund of Zhejiang Province(2024ZY01011)。
文摘Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts.
基金financially supported by the National Key R&D Program of China under grant No.2017YFB0703002the National Natural Science Foundation of China(NSFC)under grant Nos.U1664253,51901230,51871223,51790482,51771208+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences under grant No.XDB22020202the Youth Innovation Promotion Association CAS under grant No.2018226the National Science and Technology Major Project under grant No.2017-VI-0003-0073the LiaoNing Revitalization Talents Program under Grant No.XLYC1808027。
文摘The high cost and low efficiency of fatigue tests are bottleneck problem for the anti-fatigue design of metallic materials.For this problem,a theoretical fatigue model is proposed in this study,the possible applications have also been discussed.Specific results would be introduced in two serial papers,in which the first paper focuses on the model building and the applications on fatigue strength prediction;the second paper put emphasis on the influencing factors of the model parameters and the applications on fatigue strength improvement.In this first paper,a theoretical model is proposed considering both the strength and plastic restrictions of fatigue strength.As the model builds up a brief relationship among yield strength(Y),tensile strength(T)and fatigue strength(F),it is named as the Y-T-F model.Through the verification with fatigue strength data covering various kinds of metallic materials and loading conditions,this Y-T-F model exhibits both generality and accuracy.With the Y-T-F model,the efficient fatigue strength prediction could be conducted by brief linear fitting and calculation,just through yield strength,tensile strength and several known fatigue strength data.Moreover,through its deduced Y-F model,the analytical formula of fatigue strength continuously changing with materials strengthening can be obtained,as well as the maximum value of fatigue strength and corresponding critical yield strength.In summary,the Y-T-F model would be useful for reducing the fatigue tests,thus providing new possibilities on the efficient anti-fatigue design and selection of metallic materials.
基金financial support through the project Medium-Sized Centre programme R-723-000-001-281support from EU Flagship Programs (Graphene CNECTICT-604391 and 2D-SIPC Quantum Technology)European Research Council Synergy Grant Hetero2D, the Royal Society, EPSRC grants EP/N010345/1, EP/ P026850/1, EP/S030719/1.
文摘The isolation of the first two-dimensional material, graphene-a monolayer of carbon atoms arranged in a hexagonal lattice-opened new exciting opportunities in the field of condensed matter physics and materials. Its isolation and subsequent studies demonstrated that it was possible to obtain sheets of atomically thin crystals and that these were stable, and they also began to show its outstanding properties, thus opening the door to a whole new family of materials, known as two-dimensional materials or 2D materials. The great interest in different 2D materials is motivated by the variety of properties they show, being candidates for numerous applications.Additionally, the combination of 2D crystals allows the assembly of composite, on-demand materials, known as van der Waals heterostructures, which take advantage of the properties of those materials to create functionalities that otherwise would not be accessible. For example, the combination of 2D materials, which can be done with high precision, is opening up opportunities for the study of new challenges in fundamental physics and novel applications. Here we review the latest fundamental discoveries in the area of 2D materials and offer a perspective on the future of the field.
基金This research is partly supported by the scholarship from China Scholarship Council under the Grant CSC(201608060071).
文摘High flammability of polymers has become a major issue which has restricted its applications.Recently,highly crystalline materials and metal–organic frameworks(MOFs),which consisted of metal ions and organic linkers,have been intensively employed as novel fire retardants(FRs)for a variety of polymers(MOF/polymer).The MOFs possessed abundant transition metal species,fire-retardant elements and potential carbon source accompanied with the facile tuning of the structure and property,making MOF,its derivatives and MOF hybrids promising for fire retardancy research.The recent progress and strategies to prepare MOF-based FRs are emphasized and summarized.The fire retardancy mechanisms of MOF/polymer composites are explained,which may guide the future design for efficient MOF-based FRs.Finally,the challenges and prospects related to different MOFbased FRs are also discussed and aim to provide a fast and holistic overview,which is beneficial for researchers to quickly get up to speed with the latest development in this field.
