Nowadays,higher requirements are put forward to the storage and utilization of energy,and supercapacitor is a kind of energy storage electronic devices.The resulting CA-N,with a specific surface area of 320.6 m^(2)/g ...Nowadays,higher requirements are put forward to the storage and utilization of energy,and supercapacitor is a kind of energy storage electronic devices.The resulting CA-N,with a specific surface area of 320.6 m^(2)/g and a pore volume of 0.28 cm^(3)/g,demonstrated a remarkable supercapacitance of 283.3 F/g.As a mesoporous material,CA-N offers numerous channels for the diffusion and absorption of electrolyte ions.Furthermore,it exhibited an impressive capacity retention rate of 98.48% after 5000 charge-discharge cycles.These outstanding electrochemical properties highlight the potential of CA-N for applications in energy storage.展开更多
In this work,silicon-carbon hybrid materials were adopted as an example to illustrate the novel strategy to in situ construct heterostructure with adjustable microstructure.Based on the temperature-dependent thermodyn...In this work,silicon-carbon hybrid materials were adopted as an example to illustrate the novel strategy to in situ construct heterostructure with adjustable microstructure.Based on the temperature-dependent thermodynamics and kinetics of reaction between Si and C,the processes for Si nanocrystals growth and C decoration were coupled at different zones of plasma flame according to its temperature and velocity fields by theoretical modeling,aiming to intentionally suppress the formation of undesirable carbide,and enable adjusting the microstructure of each counterpart separately in transient process.As a result,well-controlled Si/C nanocomposites,including nanospheres and nanowires with core-shell structures,were achieved,and this continuous and in-flight route is also potential for large-scale production.Further investigation on the electrochemical properties highlights the advantage of as proposed strategy to efficiently construct heterostructures with superior performance for various applications.展开更多
Novel hydrogen storage materials have propelled progress in hydrogen storage technologies.Magnesium hydride(MgH_(2))is a highly promising candidate.Nevertheless,several drawbacks,including the need for elevated therma...Novel hydrogen storage materials have propelled progress in hydrogen storage technologies.Magnesium hydride(MgH_(2))is a highly promising candidate.Nevertheless,several drawbacks,including the need for elevated thermal conditions,sluggish dehydrogena-tion kinetics,and high thermodynamic stability,limit its practical application.One effective method of addressing these challenges is cata-lyst doping,which effectively boosts the hydrogen storage capability of Mg-based materials.Herein,we review recent advancements in catalyst-doped MgH_(2) composites,with particular focus on multicomponent and high-entropy catalysts.Structure-property relationships and catalytic mechanisms in these doping strategies are also summarized.Finally,based on existing challenges,we discuss future research directions for the development of Mg-based hydrogen storage systems.展开更多
Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising a...Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising as SIBs cathodes due to their high theoretical capacities and facile synthesis.However,their practical applications are hindered by the limitations in energy density and cycling stability.The comprehensive understanding of failure mechanisms within bulk structure and at the cathode/electrolyte interface of cathodes is still lacking.In this review,the issues related to bulk phase degradation and surface degradation,such as irreversible phase transitions,cation migration,transition metal dissolution,air/moisture instability,intergranular cracking,interfacial reactions,and reactive oxygen loss,are discussed.The latest advances and strategies to improve the stability of layered oxide cathodes and full cells are provided,as well as our perspectives on the future development of SIBs.展开更多
Li_(3)VO_4 has been considered as a promising insertion-type anode for lithium-ion batteries due to its high theoretical specific capacity and suitable operating voltage platform. However, this promising anode still s...Li_(3)VO_4 has been considered as a promising insertion-type anode for lithium-ion batteries due to its high theoretical specific capacity and suitable operating voltage platform. However, this promising anode still suffers from poor electrical conductivity. To address this issue, herein, a porous carbon supported Li_(3)VO_4 composites(Li_(3)VO_4/C) via a facile agitation-drying method combined with subsequent calcination is reported, in which Ketjen black carbon with high porosity, easy dispersion and excellent conductivity can serve as one of carbon sources. The Li_(3)VO_4/C composite prepared at 700 ℃ with a carbon content of~10% exhibits the optimized structure. The void space of the composite accommodates the volume changes during the charge/discharge process.Meanwhile, the carbon shell serves as a conductive skeleton to provide bi-continuous Li ions and electrons pathways. Electrochemical results reveal that the composite delivers a high initial discharge capacity of 572 m Ahág^(-1) and maintains a capacity of 442.9 m Ahág^(-1) after 100 cycles at 100 m Aág^(-1). Even at a high current density of 2 Aág^(-1), a considerable capacity of 243.8 m Ahág^(-1) can still be obtained. This work provides a promising approach for the practical application of Li_(3)VO_4 as anode material for LIBs.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
We demonstrate a case study of Ce-doped yttrium aluminum garnet(YAG)phosphor to illustrate a novel plasma route for the synthesis of multicomponent materials with addressing morphology and structural control.The prese...We demonstrate a case study of Ce-doped yttrium aluminum garnet(YAG)phosphor to illustrate a novel plasma route for the synthesis of multicomponent materials with addressing morphology and structural control.The presented strategy was started directly from liquid precursors without any precipitating agents,and an innovative growth mechanism was proposed to explain the formation of monodispersed spherical particles with an adjusted size distribution.Homogeneous elemental distribution close to that of liquid precursors was also achieved due to the thermal nonequilibrium effect in plasma.Benefiting from the structural feature of the obtained product,a low transformation temperature of 1100℃for YAG phase was obtained and final products exhibit the highest photoluminescence intensity with rather low Ce doping of 0.5 wt.%,together with excellent thermal stability of 92%preservation of initial emission at 473 K.This work well illustrates the advance of plasma strategy in formation of multicomponent com-pounds with excellent performances,and its potential for large-scale production due to the transient and in-flight synthesis process.展开更多
LiFePO_(4) is a cathode material with good thermal stability,but low thermal conductivity is a critical problem.In this study,we employ a machine learning potential approach based on first-principles methods combined ...LiFePO_(4) is a cathode material with good thermal stability,but low thermal conductivity is a critical problem.In this study,we employ a machine learning potential approach based on first-principles methods combined with the Boltzmann transport theory to investigate the influence of Na substitution on the thermal conductivity of LiFePO_(4) and the impact of Li-ion de-embedding on the thermal conductivity of Li_(3/4)Na_(1/4)FePO_(4),with the aim of enhancing heat dissipation in Li-ion batteries.The results show a significant increase in thermal conductivity due to an increase in phonon group velocity and a decrease in phonon anharmonic scattering by Na substitution.In addition,the thermal conductivity increases significantly with decreasing Li-ion concentration due to the increase in phonon lifetime.Our work guides the improvement of the thermal conductivity of Li FePO_4,emphasizing the crucial roles of both substitution and Li-ion detachment/intercalation for the thermal management of electrochemical energy storage devices.展开更多
Enhancing the lubricating properties and antibacterial adhesion resistance of implantable medical materials is critical to prevent soft tissue injury during implantation and the formation of bacterial biofilms.Prior s...Enhancing the lubricating properties and antibacterial adhesion resistance of implantable medical materials is critical to prevent soft tissue injury during implantation and the formation of bacterial biofilms.Prior studies may have exhibited limitations in the preparation methodologies and long-term stability of coatings for implantable medical materials.In this study,we developed a multilayered hybrid hydrogel coating method based on the rate difference of polymerization initiation on the material surface.The acquired coating with persistent lubrication capability retained its functionality after 2×10^(4) cycles of friction and 21 days of PBS immersion.A quaternary ammonium salt coating with antibacterial properties was introduced to further functionalize the coating.Animal experiments demonstrated that this coating exhibited remarkable effects on delaying encrustation and bacterial colonization.These studies indicate that this simple method of introducing lubricating and antibacterial coatings on catheters is likely to enhance the biocompatibility of medical devices and has broad application prospects in this field of medical devices.展开更多
In recent years,reducing carbon emissions to achieve carbon neutrality has become an urgent issue for environmental protection and sustainable development.Converting CO_(2) into valuable chemical products through elec...In recent years,reducing carbon emissions to achieve carbon neutrality has become an urgent issue for environmental protection and sustainable development.Converting CO_(2) into valuable chemical products through electrocatalysis powered by renewable electricity exhibits great potential.However,the electroreduction of CO_(2) heavily relies on efficient catalysts to overcome the required energy barrier due to the high stability of CO_(2).p-block metal-based MOFs and MOF-derived catalysts have been proven to be efficient catalysts for electrochemical CO_(2) reduction reaction(CO_(2)RR)due to their unique electronic structure and clear active sites.However,factors such as conductivity and stability limit the practical application of p-block metal-based MOFs and MOF-derived catalysts.In this review,we summarize the latest progress of MOFs and MOF-derived catalysts based on typical p-block metals in the field of CO_(2)RR.Then the modification strategies for MOFs-based catalysts and the related catalytic mechanism are briefly introduced.Furthermore,we offer the challenges and prospects of p-block metal-based MOFs and MOF-derived catalysts in the hope of providing guidance for potential applications.展开更多
Nanomaterials are extensively utilized in a multitude of sectors,but their propensity to aggregate can considerably diminish the efficacy of functional materials.A pivotal challenge in this domain is achieving a homog...Nanomaterials are extensively utilized in a multitude of sectors,but their propensity to aggregate can considerably diminish the efficacy of functional materials.A pivotal challenge in this domain is achieving a homogenous distribution of nanomaterials,which is essential for enhancing their performance while also reducing production costs.In this work,we achieve uniform and stable dispersion of various nano-materials through the confinement effect generated by the stereocomplex cross-linked network formed by the combination of poly(L-lactic)acid and poly(D-lactic)acid.The unique confinement effect of poly-lactic acid(PLA)isomers is universal and significantly enhances the dispersion of nanomaterials in both PLA solutions and films.To demonstrate the efficacy of our approach,we disperse aggregation-induced emission(AIE)molecules within PLA,which leads to the production of PLA films exhibiting improved fluorescence property.This work provides an effective solution for the preparation of nanocomposite ma-terials that are both high-performing and cost-efficient.展开更多
PrBaFe_(2)O_(5+δ)(PBF)is one of the promising cathode materials for intermediate-temperature solid oxide fuel cell(IT-SOFC)technology.However,as the operating temperature decreases,the electrochemical performance of ...PrBaFe_(2)O_(5+δ)(PBF)is one of the promising cathode materials for intermediate-temperature solid oxide fuel cell(IT-SOFC)technology.However,as the operating temperature decreases,the electrochemical performance of this material deteriorates rapidly.To counter this,various doping strategies have been tested and reported in order to improve the electrochemical properties of this material at intermediate-temperatures.In this study,Mg-doping to partially substitute Fe of PBF was investigated.PrBaFe_(2-x)Mg_(x)O_(5+δ)(PBFMgx,x=0.1,0.15,0.2,0.3)materials were successfully synthesized,and their electrochemical performance as IT-SOFC cathode was evaluated.It is shown that Mg-doping enhances the conductivity of PBF between 650 and 800℃,impacts little on the area-specific resistance of oxygen reduction reaction at and above 700℃,and,most significantly,improves the power density of the NiSDC/SDC/PBFMg0.15single cell by 52%compared to the un-doped PBF.This enhanced electrochemical performance is attributed to the improvement in PBF conductivity by Mg-doping.展开更多
The ultra-high nickel cathode material has important application prospect in power lithium-ion batteries.However,the poor structural stability and serious surface/interfacial side reactions during long cycles severely...The ultra-high nickel cathode material has important application prospect in power lithium-ion batteries.However,the poor structural stability and serious surface/interfacial side reactions during long cycles severely hinder the material's practical application.In this paper,Cs^(+)doping and polymethyl methacrylate(PMMA)coating are used to synergistically modify the NCM955 material.The results show that the corresponding discharge specific capacity of NCMCs-2@P-2 material reaches 152.02 m Ah/g at 1 C(1 C=200 m A/g)and 125.66 m Ah/g at 5 C after 300 cycles,and the capacity retention is 78.11%and72.21%,respectively.In addition,it still maintains 156.36 m Ah/g discharge specific capacity at 10 C,and these rate and cycle properties exceed those reported on ultra-high nickel cathode material.Moreover,NCMCs-2@P-2 material has higher migration energy barrier of Ni^(2+)and lower migration energy barrier of Li+than that of NCM955 material.Therefore,NCMCs-2@P-2 material has excellent electrochemical properties,which has been proved by a series of structural characterization,theoretical calculation and performance test.The synergistic enhancement of Cs^(+)doping and PMMA coating accelerates lithium ion diffusion kinetics,stabilizes crystal structure,and inhabits surface/interface side reaction.展开更多
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam...Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering.展开更多
The aqueous preparation of Na_(3)(VOPO_(4))_(2)F cathode material with low cost and good structural stability has attracted extensive attention for advancing sodium-ion batteries(SIBs).However,the inclusive heterogene...The aqueous preparation of Na_(3)(VOPO_(4))_(2)F cathode material with low cost and good structural stability has attracted extensive attention for advancing sodium-ion batteries(SIBs).However,the inclusive heterogeneous cations incorporated into the material lattice,dominated by coordination chemistry,are always overlooked.Herein,the embroiled NH_(4)^(+)/H_(3)O^(+)cations in the Na_(3)(VOPO_(4))_(2)F lattice have been first disclosed during aqueous co-precipitation.It involves the electrostatic interactions between hydrogen protons(NH_(4)^(+)/H_(3)O^(+))and electronegative oxygen atoms(V=O and V–O–P groups),which induces the terrible Na^(+)-storage performance,as demonstrated by multiple characterizations.Followingly,the very-facile operation,i.e.heat treatment,has been raised to remove NH_(4)^(+)/H_(3)O^(+)cations and then achieved high-performance Na_(3)(VOPO_(4))_(2)F.Therefore,the Na_(3)(VOPO_(4))_(2)F||Na cell contributes to the significantly improved discharge capacity(129.7 mAh g^(−1))and voltage plateau from 3.63 to 3.87 V(vs.Na/Na^(+))at 0.2 C.The ultrahigh capacity retentions of 93.7%and 76.7%after 1000 and 3500 cycles at 1 and 20 C rates under 25°C are harvested,respectively,as well as high/low-temperature performances and rate capability.Eventually,the as-assembled Na_(3)(VOPO_(4))_(2)F||hard carbon full-cell delivers excellent long-term cycling stability over 1000 cycles with 97.5%retention at 3 C.These emphasize the high-efficacy synthesis of Na_(3)(VOPO_(4))_(2)F and provide insights into the aqueous co-precipitation for the development of materials used in SIBs.展开更多
Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely comme...Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely commercial application and development of LSB is mainly hindered by serious“shuttle effect”of lithium polysulfides(Li PSs),slow reaction kinetics,notorious lithium dendrites,etc.In various structures of LSB materials,array structured materials,possessing the composition of ordered micro units with the same or similar characteristics of each unit,present excellent application potential for various secondary cells due to some merits such as immobilization of active substances,high specific surface area,appropriate pore sizes,easy modification of functional material surface,accommodated huge volume change,enough facilitated transportation for electrons/lithium ions,and special functional groups strongly adsorbing Li PSs.Thus many novel array structured materials are applied to battery for tackling thorny problems mentioned above.In this review,recent progresses and developments on array structured materials applied in LSBs including preparation ways,collaborative structural designs based on array structures,and action mechanism analyses in improving electrochemical performance and safety are summarized.Meanwhile,we also have detailed discussion for array structured materials in LSBs and constructed the structure-function relationships between array structured materials and battery performances.Lastly,some directions and prospects about preparation ways,functional modifications,and practical applications of array structured materials in LSBs are generalized.We hope the review can attract more researchers'attention and bring more studying on array structured materials for other secondary batteries including LSB.展开更多
Catalytic reduction reactions using isopropanol(IPA)as a transfer hydrogenating agent are gaining significant attention due to the low cost and large-scale production of IPA.Traditional methods for carbon-carbon(C—C)...Catalytic reduction reactions using isopropanol(IPA)as a transfer hydrogenating agent are gaining significant attention due to the low cost and large-scale production of IPA.Traditional methods for carbon-carbon(C—C)bond construction often rely on expensive and scarce transition metal catalysts,raising concerns about sustainability and environmental impact.To address these challenges,we develop a bifunctional photocatalyst,phloroglucinol carbon quantum dot(PG-CQD).It facilitates catalytic transfer hydrogenation(CTH)with IPA as the hydrogen donor.PG-CQDs exhibit both dehydrogenation and reduction activities,enabling the formation of vicinal diols under mild conditions with visible light irradiation.We propose a CTH mechanism that has been successfully validated through experiments.The catalytic system demonstrates remarkable versatility,enabling the synthesis of various vicinal diols from diverseα-keto ester substrates with good or excellent yields.These findings offer a sustainable synthetic strategy that aligns with green chemistry principles and establish a promising pathway for the development of environmentally benign and energy-efficient organic transformations.展开更多
A novel trace nickel(Ni)doped tungsten(W)matrix with coated Ni on W grains was prepared by powder metallurgy method.The introduction of Ni can inhibit the reaction between W and barium-calcium aluminates(Ba-Ca alumina...A novel trace nickel(Ni)doped tungsten(W)matrix with coated Ni on W grains was prepared by powder metallurgy method.The introduction of Ni can inhibit the reaction between W and barium-calcium aluminates(Ba-Ca aluminates)during the impregnation process of the matrix.After cathode activation,the surface Ba:O molar ratio is 0.88:1.00,much higher than the Ba dispenser cathode without Ni doping.The XPS results of the cathode surface showed that the metallic Ba appeared on the activated cathode surface,forming dipoles with oxygen,and effectively reducing the cathode surface work function.The pulse electron emission current density at 1100℃_(b)(brightness temperature)was 18.26 A/cm^(2),and the calculated work function was 1.97 eV.It has a low evaporation rate and the accelerated lifetime test predict a lifetime of over 160000 h.First-principles calculations showed that the charge transfer and dipole moment in the NiW-BaO system were both increased compared to the Ba dispenser cathode,thus improving the emission performance of the Ni-W mixed matrix cathode.展开更多
To address the poor mechanical performance and improve the tribological properties of self-lubricating polyphenylene sulfide/irradiation treated polytetrafluoroethylene(PPS/i-PTFE)blends,different aspect ratio carbon ...To address the poor mechanical performance and improve the tribological properties of self-lubricating polyphenylene sulfide/irradiation treated polytetrafluoroethylene(PPS/i-PTFE)blends,different aspect ratio carbon fibers(i.e.,PSCF:50,SCF:about 429)were introduced as reinforcement fillers.The results showed that the hybriding of PSCF and SCF at certain mass ratios exhibited simultaneous enhancement of mechanical and tribological performance for PPS/i-PTFE blend through the construction of synergistic lubrication and mechanical interlocking network.Specifically,the flexural strength and modulus of PPS/i-PTFE were increased by 125.6% and 389.3%,the friction coefficient and specific wear rate were decreased by 13.9% and 95%,respectively.It was worth noting that PPS composites possessed excellent integrated performance which were able to withstand sliding action under high PV(≥10 MPa·m/s)conditions,as assessed by a customized pin-on-disc tester.This work demonstrated that the formation of intact lubricating film combined with the enhanced thermal and mechanical properties were favorable for improving the tribological properties of PPS-based composites,which makes them suitable for advanced engineering applications.展开更多
Halide perovskite materials have received considerable attention for solar cells,LEDs,lasers etc.owing to their controllable physicochemical properties and structural advantages.However,little research has focused on ...Halide perovskite materials have received considerable attention for solar cells,LEDs,lasers etc.owing to their controllable physicochemical properties and structural advantages.However,little research has focused on energy storage and conversion applications,such as use as anodes in lithium-ion batteries.In this paper,all-inorganic lead-free halide perovskite Cs_(3)Bi_(2)Cl_(9)powders were synthesized by the grinding method,and the lattice was successfully adjusted via introducing Mn^(2+).The characterization results show that Mn-ion substitution can cause local lattice distortion to restructure the lattice,which will cause a mixed arrangement of[BiCl_(6)]octahedra to improve the performance of the anode material.This new material can provide a feasible solution for solving the problem of low specific capacity anode materials caused by unstable crystal structures,and also indicates that such perovskites with unique crystal structures and lattice tunability have broad application prospects in lithium-ion batteries.展开更多
基金supported by Shenzhen Science and Technology Program(No.JCYJ20240813103608012)State Key Laboratory of New Textile Materials andAdvanced Processing Technologies(No.FZ2024019)National Natural Science Foundation of China(No.22104117).
文摘Nowadays,higher requirements are put forward to the storage and utilization of energy,and supercapacitor is a kind of energy storage electronic devices.The resulting CA-N,with a specific surface area of 320.6 m^(2)/g and a pore volume of 0.28 cm^(3)/g,demonstrated a remarkable supercapacitance of 283.3 F/g.As a mesoporous material,CA-N offers numerous channels for the diffusion and absorption of electrolyte ions.Furthermore,it exhibited an impressive capacity retention rate of 98.48% after 5000 charge-discharge cycles.These outstanding electrochemical properties highlight the potential of CA-N for applications in energy storage.
基金financially supported by the National Natural Science Foundation of China(No.52174342)Beijing Natural Sci-ence Foundation(No.2232044)Beijing Municipal Education Commission Research Plan General Project(No.KM202410005009).
文摘In this work,silicon-carbon hybrid materials were adopted as an example to illustrate the novel strategy to in situ construct heterostructure with adjustable microstructure.Based on the temperature-dependent thermodynamics and kinetics of reaction between Si and C,the processes for Si nanocrystals growth and C decoration were coupled at different zones of plasma flame according to its temperature and velocity fields by theoretical modeling,aiming to intentionally suppress the formation of undesirable carbide,and enable adjusting the microstructure of each counterpart separately in transient process.As a result,well-controlled Si/C nanocomposites,including nanospheres and nanowires with core-shell structures,were achieved,and this continuous and in-flight route is also potential for large-scale production.Further investigation on the electrochemical properties highlights the advantage of as proposed strategy to efficiently construct heterostructures with superior performance for various applications.
基金financially supported by the National Key Research and Development Program of China (No. 2021YFB4000604)the National Natural Science Foundation of China (No. 52271220)+2 种基金the 111 Project (No. B12015)the Fundamental Research Funds for the Central UniversitiesHaihe Laboratory of Sustainable Chemical Transformations, Guangxi Collaborative Innovation Centre of Structure and Property for New Energy and Materials, Science Research and Technology Development Project of Guilin (No. 20210102-4)
文摘Novel hydrogen storage materials have propelled progress in hydrogen storage technologies.Magnesium hydride(MgH_(2))is a highly promising candidate.Nevertheless,several drawbacks,including the need for elevated thermal conditions,sluggish dehydrogena-tion kinetics,and high thermodynamic stability,limit its practical application.One effective method of addressing these challenges is cata-lyst doping,which effectively boosts the hydrogen storage capability of Mg-based materials.Herein,we review recent advancements in catalyst-doped MgH_(2) composites,with particular focus on multicomponent and high-entropy catalysts.Structure-property relationships and catalytic mechanisms in these doping strategies are also summarized.Finally,based on existing challenges,we discuss future research directions for the development of Mg-based hydrogen storage systems.
基金supported by the National Natural Science Foundation of China(Grant No.W2412060,22325902 and 52171215)the State Key Laboratory of Clean Energy Utilization(Open Fund Project No.ZJUCEU2023002)。
文摘Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising as SIBs cathodes due to their high theoretical capacities and facile synthesis.However,their practical applications are hindered by the limitations in energy density and cycling stability.The comprehensive understanding of failure mechanisms within bulk structure and at the cathode/electrolyte interface of cathodes is still lacking.In this review,the issues related to bulk phase degradation and surface degradation,such as irreversible phase transitions,cation migration,transition metal dissolution,air/moisture instability,intergranular cracking,interfacial reactions,and reactive oxygen loss,are discussed.The latest advances and strategies to improve the stability of layered oxide cathodes and full cells are provided,as well as our perspectives on the future development of SIBs.
基金financially supported by the National Natural Science Foundation of China (Nos. 51874362 and51872334)the Natural Science Foundation of Hunan Province,China(No. 2018JJ1036)the National Key Research and Development Program of China (No. 2018YFB0104200)。
文摘Li_(3)VO_4 has been considered as a promising insertion-type anode for lithium-ion batteries due to its high theoretical specific capacity and suitable operating voltage platform. However, this promising anode still suffers from poor electrical conductivity. To address this issue, herein, a porous carbon supported Li_(3)VO_4 composites(Li_(3)VO_4/C) via a facile agitation-drying method combined with subsequent calcination is reported, in which Ketjen black carbon with high porosity, easy dispersion and excellent conductivity can serve as one of carbon sources. The Li_(3)VO_4/C composite prepared at 700 ℃ with a carbon content of~10% exhibits the optimized structure. The void space of the composite accommodates the volume changes during the charge/discharge process.Meanwhile, the carbon shell serves as a conductive skeleton to provide bi-continuous Li ions and electrons pathways. Electrochemical results reveal that the composite delivers a high initial discharge capacity of 572 m Ahág^(-1) and maintains a capacity of 442.9 m Ahág^(-1) after 100 cycles at 100 m Aág^(-1). Even at a high current density of 2 Aág^(-1), a considerable capacity of 243.8 m Ahág^(-1) can still be obtained. This work provides a promising approach for the practical application of Li_(3)VO_4 as anode material for LIBs.
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supported by the National Natu-ral Science Foundation of China(No.52174342)the Beijing Nat-ural Science Foundation(No.2232044)the Beijing Munic-ipal Education Commission Research Plan General Project(No.KM202410005009).
文摘We demonstrate a case study of Ce-doped yttrium aluminum garnet(YAG)phosphor to illustrate a novel plasma route for the synthesis of multicomponent materials with addressing morphology and structural control.The presented strategy was started directly from liquid precursors without any precipitating agents,and an innovative growth mechanism was proposed to explain the formation of monodispersed spherical particles with an adjusted size distribution.Homogeneous elemental distribution close to that of liquid precursors was also achieved due to the thermal nonequilibrium effect in plasma.Benefiting from the structural feature of the obtained product,a low transformation temperature of 1100℃for YAG phase was obtained and final products exhibit the highest photoluminescence intensity with rather low Ce doping of 0.5 wt.%,together with excellent thermal stability of 92%preservation of initial emission at 473 K.This work well illustrates the advance of plasma strategy in formation of multicomponent com-pounds with excellent performances,and its potential for large-scale production due to the transient and in-flight synthesis process.
基金supported by the National Natural Science Foundation of China(Grant No.12074115)the Science and Technology Innovation Program of Hunan Province(Grant No.2023RC3176)。
文摘LiFePO_(4) is a cathode material with good thermal stability,but low thermal conductivity is a critical problem.In this study,we employ a machine learning potential approach based on first-principles methods combined with the Boltzmann transport theory to investigate the influence of Na substitution on the thermal conductivity of LiFePO_(4) and the impact of Li-ion de-embedding on the thermal conductivity of Li_(3/4)Na_(1/4)FePO_(4),with the aim of enhancing heat dissipation in Li-ion batteries.The results show a significant increase in thermal conductivity due to an increase in phonon group velocity and a decrease in phonon anharmonic scattering by Na substitution.In addition,the thermal conductivity increases significantly with decreasing Li-ion concentration due to the increase in phonon lifetime.Our work guides the improvement of the thermal conductivity of Li FePO_4,emphasizing the crucial roles of both substitution and Li-ion detachment/intercalation for the thermal management of electrochemical energy storage devices.
基金financially supported by the National Natural Science Foundation of China(Nos.52373296 and 52173287)。
文摘Enhancing the lubricating properties and antibacterial adhesion resistance of implantable medical materials is critical to prevent soft tissue injury during implantation and the formation of bacterial biofilms.Prior studies may have exhibited limitations in the preparation methodologies and long-term stability of coatings for implantable medical materials.In this study,we developed a multilayered hybrid hydrogel coating method based on the rate difference of polymerization initiation on the material surface.The acquired coating with persistent lubrication capability retained its functionality after 2×10^(4) cycles of friction and 21 days of PBS immersion.A quaternary ammonium salt coating with antibacterial properties was introduced to further functionalize the coating.Animal experiments demonstrated that this coating exhibited remarkable effects on delaying encrustation and bacterial colonization.These studies indicate that this simple method of introducing lubricating and antibacterial coatings on catheters is likely to enhance the biocompatibility of medical devices and has broad application prospects in this field of medical devices.
基金supported by the National Natural Science Foundation of China(Nos.22061019 and 22261021)the Jiangxi Provincial Natural Science Foundation(Nos.20224BAB203002,20232ACB203018,20232BAB203005,and 20224BAB213001)+5 种基金the Jiangxi Province Key Laboratory of Functional Crystalline Materials Chemistry(No.2024SSY05161)the Ganzhou Key Research and Development Program(No.2023PNS26963)the Youth Jinggang Scholars Program in Jiangxi Province(No.QNJG2019053)the Two Thousand Talents Program in Jiangxi Province(No.jxsq2019201068)the Doctor’s Starting Research Foundation of Jiangxi University of Science and Technology(No.205200100597)the Science and Technology Research Project of Jiangxi Provincial Department of Education(No.GJJ2200860).
文摘In recent years,reducing carbon emissions to achieve carbon neutrality has become an urgent issue for environmental protection and sustainable development.Converting CO_(2) into valuable chemical products through electrocatalysis powered by renewable electricity exhibits great potential.However,the electroreduction of CO_(2) heavily relies on efficient catalysts to overcome the required energy barrier due to the high stability of CO_(2).p-block metal-based MOFs and MOF-derived catalysts have been proven to be efficient catalysts for electrochemical CO_(2) reduction reaction(CO_(2)RR)due to their unique electronic structure and clear active sites.However,factors such as conductivity and stability limit the practical application of p-block metal-based MOFs and MOF-derived catalysts.In this review,we summarize the latest progress of MOFs and MOF-derived catalysts based on typical p-block metals in the field of CO_(2)RR.Then the modification strategies for MOFs-based catalysts and the related catalytic mechanism are briefly introduced.Furthermore,we offer the challenges and prospects of p-block metal-based MOFs and MOF-derived catalysts in the hope of providing guidance for potential applications.
基金supported by the National Key R&D Program of China(No.2022YFB3804204)the National Natural Science Foundation of China(Nos.52127805,52102090,12172005,and 12325202)+1 种基金the Fundamental Research Funds for the Central Uni-versities(No.2232022D-04)the Innovation and Development Sup-port Plan for Key Industries in Southern Xinjiang(No.2022DB011).
文摘Nanomaterials are extensively utilized in a multitude of sectors,but their propensity to aggregate can considerably diminish the efficacy of functional materials.A pivotal challenge in this domain is achieving a homogenous distribution of nanomaterials,which is essential for enhancing their performance while also reducing production costs.In this work,we achieve uniform and stable dispersion of various nano-materials through the confinement effect generated by the stereocomplex cross-linked network formed by the combination of poly(L-lactic)acid and poly(D-lactic)acid.The unique confinement effect of poly-lactic acid(PLA)isomers is universal and significantly enhances the dispersion of nanomaterials in both PLA solutions and films.To demonstrate the efficacy of our approach,we disperse aggregation-induced emission(AIE)molecules within PLA,which leads to the production of PLA films exhibiting improved fluorescence property.This work provides an effective solution for the preparation of nanocomposite ma-terials that are both high-performing and cost-efficient.
基金supported by the National Natural Science Foundation of China(51974167)Natural Science Foundation Youth Foundation of Inner Mongolia(2023QN05038)Higher Education Carbon Peak Carbon Neutral Research Project of Inner Mongolia Autonomous Region(STZX202210)。
文摘PrBaFe_(2)O_(5+δ)(PBF)is one of the promising cathode materials for intermediate-temperature solid oxide fuel cell(IT-SOFC)technology.However,as the operating temperature decreases,the electrochemical performance of this material deteriorates rapidly.To counter this,various doping strategies have been tested and reported in order to improve the electrochemical properties of this material at intermediate-temperatures.In this study,Mg-doping to partially substitute Fe of PBF was investigated.PrBaFe_(2-x)Mg_(x)O_(5+δ)(PBFMgx,x=0.1,0.15,0.2,0.3)materials were successfully synthesized,and their electrochemical performance as IT-SOFC cathode was evaluated.It is shown that Mg-doping enhances the conductivity of PBF between 650 and 800℃,impacts little on the area-specific resistance of oxygen reduction reaction at and above 700℃,and,most significantly,improves the power density of the NiSDC/SDC/PBFMg0.15single cell by 52%compared to the un-doped PBF.This enhanced electrochemical performance is attributed to the improvement in PBF conductivity by Mg-doping.
基金supported the National Science Foundation of China(Nos.22362011,22169007,51804199)the Science and Technology Major Project of Guangxi(No.AA19046001)+2 种基金the Open Research Fund of Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials(Nos.EMFM20201105,EMFM20181119)Shenzhen Medical Research Fund(No.20231211121324001)Shenzhen Science and Technology Program(No.KQTD20180412181422399)。
文摘The ultra-high nickel cathode material has important application prospect in power lithium-ion batteries.However,the poor structural stability and serious surface/interfacial side reactions during long cycles severely hinder the material's practical application.In this paper,Cs^(+)doping and polymethyl methacrylate(PMMA)coating are used to synergistically modify the NCM955 material.The results show that the corresponding discharge specific capacity of NCMCs-2@P-2 material reaches 152.02 m Ah/g at 1 C(1 C=200 m A/g)and 125.66 m Ah/g at 5 C after 300 cycles,and the capacity retention is 78.11%and72.21%,respectively.In addition,it still maintains 156.36 m Ah/g discharge specific capacity at 10 C,and these rate and cycle properties exceed those reported on ultra-high nickel cathode material.Moreover,NCMCs-2@P-2 material has higher migration energy barrier of Ni^(2+)and lower migration energy barrier of Li+than that of NCM955 material.Therefore,NCMCs-2@P-2 material has excellent electrochemical properties,which has been proved by a series of structural characterization,theoretical calculation and performance test.The synergistic enhancement of Cs^(+)doping and PMMA coating accelerates lithium ion diffusion kinetics,stabilizes crystal structure,and inhabits surface/interface side reaction.
基金Supported by the National Natural Science Foundation of China(Nos.52293472,22473096 and 22471164)。
文摘Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering.
基金the Natural Science Foundation of China(52162030,52272234,52172233)the Major Science and Technology Projects of Yunnan Province(202202AG050003)+7 种基金the Yunnan Thousand Talents Program for Young Talents(KKS2202052001,KKRD202252091)the Yunnan Fundamental Research Projects(202401AT070368,202401AU070163)the Scientific Research Foundation of Kunming University of Science and Technology(20220122)the Analysis and Test Foundation of Kunming University of Science and Technology(2023T20220122)the Yunnan Engineering Research Center Innovation Ability Construction and Enhancement Projects(2023-XMDJ00617107)the National Key Research and Development Program of China(2020YFA0715000)the International Science and Technology Cooperation Program of Hubei Province(2024EHA039)the Independent Innovation Project of Hubei Longzhong Laboratory(2022ZZ-20).
文摘The aqueous preparation of Na_(3)(VOPO_(4))_(2)F cathode material with low cost and good structural stability has attracted extensive attention for advancing sodium-ion batteries(SIBs).However,the inclusive heterogeneous cations incorporated into the material lattice,dominated by coordination chemistry,are always overlooked.Herein,the embroiled NH_(4)^(+)/H_(3)O^(+)cations in the Na_(3)(VOPO_(4))_(2)F lattice have been first disclosed during aqueous co-precipitation.It involves the electrostatic interactions between hydrogen protons(NH_(4)^(+)/H_(3)O^(+))and electronegative oxygen atoms(V=O and V–O–P groups),which induces the terrible Na^(+)-storage performance,as demonstrated by multiple characterizations.Followingly,the very-facile operation,i.e.heat treatment,has been raised to remove NH_(4)^(+)/H_(3)O^(+)cations and then achieved high-performance Na_(3)(VOPO_(4))_(2)F.Therefore,the Na_(3)(VOPO_(4))_(2)F||Na cell contributes to the significantly improved discharge capacity(129.7 mAh g^(−1))and voltage plateau from 3.63 to 3.87 V(vs.Na/Na^(+))at 0.2 C.The ultrahigh capacity retentions of 93.7%and 76.7%after 1000 and 3500 cycles at 1 and 20 C rates under 25°C are harvested,respectively,as well as high/low-temperature performances and rate capability.Eventually,the as-assembled Na_(3)(VOPO_(4))_(2)F||hard carbon full-cell delivers excellent long-term cycling stability over 1000 cycles with 97.5%retention at 3 C.These emphasize the high-efficacy synthesis of Na_(3)(VOPO_(4))_(2)F and provide insights into the aqueous co-precipitation for the development of materials used in SIBs.
基金This work was supported by the National Natural Science Foundation of China(52203066,51973157,61904123)the Tianjin Natural Science Foundation(18JCQNJC02900)+3 种基金the National innovation and entrepreneurship training program for college students(202310058007)the Tianjin Municipal college students’innovation and entrepreneurship training program(202310058088)the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(Grant No.2018KJ196)the State Key Laboratory of Membrane and Membrane Separation,Tiangong University.
文摘Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely commercial application and development of LSB is mainly hindered by serious“shuttle effect”of lithium polysulfides(Li PSs),slow reaction kinetics,notorious lithium dendrites,etc.In various structures of LSB materials,array structured materials,possessing the composition of ordered micro units with the same or similar characteristics of each unit,present excellent application potential for various secondary cells due to some merits such as immobilization of active substances,high specific surface area,appropriate pore sizes,easy modification of functional material surface,accommodated huge volume change,enough facilitated transportation for electrons/lithium ions,and special functional groups strongly adsorbing Li PSs.Thus many novel array structured materials are applied to battery for tackling thorny problems mentioned above.In this review,recent progresses and developments on array structured materials applied in LSBs including preparation ways,collaborative structural designs based on array structures,and action mechanism analyses in improving electrochemical performance and safety are summarized.Meanwhile,we also have detailed discussion for array structured materials in LSBs and constructed the structure-function relationships between array structured materials and battery performances.Lastly,some directions and prospects about preparation ways,functional modifications,and practical applications of array structured materials in LSBs are generalized.We hope the review can attract more researchers'attention and bring more studying on array structured materials for other secondary batteries including LSB.
基金National Natural Science Foundation of China(Nos.21902023 and 21901252)Shanghai Pujiang Program,China(No.19PJ1400300)+1 种基金Professor of Special Appointment(Eastern Scholar),ChinaShanghai Institutions of Higher Education Fundamental Research Funds for the Central Universities,China(No.0900000155)。
文摘Catalytic reduction reactions using isopropanol(IPA)as a transfer hydrogenating agent are gaining significant attention due to the low cost and large-scale production of IPA.Traditional methods for carbon-carbon(C—C)bond construction often rely on expensive and scarce transition metal catalysts,raising concerns about sustainability and environmental impact.To address these challenges,we develop a bifunctional photocatalyst,phloroglucinol carbon quantum dot(PG-CQD).It facilitates catalytic transfer hydrogenation(CTH)with IPA as the hydrogen donor.PG-CQDs exhibit both dehydrogenation and reduction activities,enabling the formation of vicinal diols under mild conditions with visible light irradiation.We propose a CTH mechanism that has been successfully validated through experiments.The catalytic system demonstrates remarkable versatility,enabling the synthesis of various vicinal diols from diverseα-keto ester substrates with good or excellent yields.These findings offer a sustainable synthetic strategy that aligns with green chemistry principles and establish a promising pathway for the development of environmentally benign and energy-efficient organic transformations.
基金supported by the National Natural Science Foundation of China(Nos.U2341209 and 52130407).
文摘A novel trace nickel(Ni)doped tungsten(W)matrix with coated Ni on W grains was prepared by powder metallurgy method.The introduction of Ni can inhibit the reaction between W and barium-calcium aluminates(Ba-Ca aluminates)during the impregnation process of the matrix.After cathode activation,the surface Ba:O molar ratio is 0.88:1.00,much higher than the Ba dispenser cathode without Ni doping.The XPS results of the cathode surface showed that the metallic Ba appeared on the activated cathode surface,forming dipoles with oxygen,and effectively reducing the cathode surface work function.The pulse electron emission current density at 1100℃_(b)(brightness temperature)was 18.26 A/cm^(2),and the calculated work function was 1.97 eV.It has a low evaporation rate and the accelerated lifetime test predict a lifetime of over 160000 h.First-principles calculations showed that the charge transfer and dipole moment in the NiW-BaO system were both increased compared to the Ba dispenser cathode,thus improving the emission performance of the Ni-W mixed matrix cathode.
基金financially supported by the National Natural Science Foundation of China(No.52103040)China Postdoctoral Science Foundation(No.2020M673217)the Fundamental Research Funds for the Central Universities(No.2023SCU12022)。
文摘To address the poor mechanical performance and improve the tribological properties of self-lubricating polyphenylene sulfide/irradiation treated polytetrafluoroethylene(PPS/i-PTFE)blends,different aspect ratio carbon fibers(i.e.,PSCF:50,SCF:about 429)were introduced as reinforcement fillers.The results showed that the hybriding of PSCF and SCF at certain mass ratios exhibited simultaneous enhancement of mechanical and tribological performance for PPS/i-PTFE blend through the construction of synergistic lubrication and mechanical interlocking network.Specifically,the flexural strength and modulus of PPS/i-PTFE were increased by 125.6% and 389.3%,the friction coefficient and specific wear rate were decreased by 13.9% and 95%,respectively.It was worth noting that PPS composites possessed excellent integrated performance which were able to withstand sliding action under high PV(≥10 MPa·m/s)conditions,as assessed by a customized pin-on-disc tester.This work demonstrated that the formation of intact lubricating film combined with the enhanced thermal and mechanical properties were favorable for improving the tribological properties of PPS-based composites,which makes them suitable for advanced engineering applications.
基金supported by the Foundation of Yunnan Province(Nos.202301AU070021,202201BE070001-027)the Test Foundation of KUST(No.2022T20210208).
文摘Halide perovskite materials have received considerable attention for solar cells,LEDs,lasers etc.owing to their controllable physicochemical properties and structural advantages.However,little research has focused on energy storage and conversion applications,such as use as anodes in lithium-ion batteries.In this paper,all-inorganic lead-free halide perovskite Cs_(3)Bi_(2)Cl_(9)powders were synthesized by the grinding method,and the lattice was successfully adjusted via introducing Mn^(2+).The characterization results show that Mn-ion substitution can cause local lattice distortion to restructure the lattice,which will cause a mixed arrangement of[BiCl_(6)]octahedra to improve the performance of the anode material.This new material can provide a feasible solution for solving the problem of low specific capacity anode materials caused by unstable crystal structures,and also indicates that such perovskites with unique crystal structures and lattice tunability have broad application prospects in lithium-ion batteries.
