Four groups of nano barium titanate powders were prepared using the hydrothermal method.Their phase structure,microscopic morphology and electrical properties were investigated,and the impacts of raw materials on the ...Four groups of nano barium titanate powders were prepared using the hydrothermal method.Their phase structure,microscopic morphology and electrical properties were investigated,and the impacts of raw materials on the barium titanate powders as well as the reaction mechanisms were explored.XRD and FTIR indicate the presence of hydroxyl groups and a small amount of carboxyl groups on the powder surface,and the choice of raw materials significantly affects phase purity,with H_(2)TiO_(3)as raw materials being prone to introducing impurity phases.SEM shows that different precursors lead to morphological differences:soluble raw materials form uniform nanoparticles through a"dissolution-precipitation"mechanism while using TiO_(2)as the titanium source generates hollow bowl-like structures through an"in-situ transformation"mechanism,attributed to the synergistic effects of Ostwald ripening and Kirkendall diffusion.The dielectric properties tests indicate that the dielectric constant at room temperature(1500-3000)and Curie temperature(2000-5000)of the ceramics are both lower than those of ceramics produced by solid-state methods(4000-6000 and>10000),and the phase transition temperature range is widened,which is attributed to factors such as grain refinement,reduced tetragonality,grain boundary effects,and increased defects.展开更多
To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content ...To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced.展开更多
In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented...In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs.展开更多
Alkali-free SiO_(2)-Al_(2)O_(3)-CaO-MgO with different SiO_(2)/Al_(2)O_(3)mass ratios was prepared by conventional melt quenching method.The glass network structure,thermodynamic properties and elastic modulus changes...Alkali-free SiO_(2)-Al_(2)O_(3)-CaO-MgO with different SiO_(2)/Al_(2)O_(3)mass ratios was prepared by conventional melt quenching method.The glass network structure,thermodynamic properties and elastic modulus changes with SiO_(2)and Al_(2)O_(3)ratios were investigated using various techniques.It is found that when SiO_(2)is replaced by Al_(2)O_(3),the Q^(4) to Q^(3) transition of silicon-oxygen network decreases while the aluminum-oxygen network increases,which result in the transformation of Si-O-Si bonds to Si-O-Al bonds and an increase in glass network connectivity even though the intermolecular bond strength decreases.The glass transition temperature(T_(g))increases continuously,while the thermal expansion coefficient increases and high-temperature viscosity first decreases and then increases.Meanwhile,the elastic modulus values increase from 93 to 102 GPa.This indicates that the elastic modulus is mainly affected by packing factor and dissociation energy,and elements with higher packing factors and dissociation energies supplant those with lower values,resulting in increased rigidity within the glass.展开更多
Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is p...Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is proposed.The electric field applied between the template and the substrate drives the contact,tilting,filling,and holding processes.By accurately controlling the introduced included angle between the flexible template and the substrate,tilted nanostructures with a controllable angle are imprinted onto the substrate,although they are vertical on the template.By flexibly adjusting the electric field intensity and the included angle,large-area uniform-tilted,gradient-tilted,and high-angle-tilted nanostructures are fabricated.In contrast to traditional replication,the morphology of the nanoimprinting structure is extended to customized control.This work provides a cost-effective,efficient,and versatile technology for the fabrication of various large-area tilted metasurface structures.As an illustration,a tilted nanograting with a high coupling efficiency is fabricated and integrated into augmented reality displays,demonstrating superior imaging quality.展开更多
Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspher...Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspheres.And modification of the pore structure is one of the effective strategies.In this study,multi-cavity mesoporous carbon microspheres were successfully synthesized by the synergistic method of soft and hard templates,during which a phenolic resin with superior thermal stability was employed as the carbon precursor and a mixture of silica sol and F108 as the mesoporous template.Carbon microspheres with multi-cavity mesoporous structures were prepared,and all the samples showed highly even mesopores,with diameters around 12 nm.The diameter of these microspheres decreased from 396.8 nm to about 182.5 nm with the increase of silica sol.After CO_(2) activation,these novel carbon microspheres(APCF0.5-S1.75)demonstrated high specific surface area(983.3 m^(2)/g)and remarkable CO_(2) uptake of 4.93 mmol/g at 0℃ and1 bar.This could be attributed to the unique multi-cavity structure,which offers uniform mesoporous pore channels,minimal CO_(2) transport of and a greater number of active sites for CO_(2) adsorption.展开更多
Aqueous zinc-ion batteries(AZIBs)have garnered considerable attention as promising post-lithium energy storage technologies owing to their intrinsic safety,cost-effectiveness,and competitive gravimetric energy density...Aqueous zinc-ion batteries(AZIBs)have garnered considerable attention as promising post-lithium energy storage technologies owing to their intrinsic safety,cost-effectiveness,and competitive gravimetric energy density.However,their practical commercialization is hindered by critical challenges on the anode side,including dendrite growth and parasitic reactions at the anode/electrolyte interface.Recent studies highlight that rational electrolyte structure engineering offers an effective route to mitigate these issues and strengthen the electrochemical performance of the zinc metal anode.In this review,we systematically summarize state-of-the-art strategies for electrolyte optimization,with a particular focus on the zinc salts regulation,electrolyte additives,and the construction of novel electrolytes,while elucidating the underlying design principles.We further discuss the key structure–property relationships governing electrolyte behavior to provide guidance for the development of next-generation electrolytes.Finally,future perspectives on advanced electrolyte design are proposed.This review aims to serve as a comprehensive reference for researchers exploring high-performance electrolyte engineering in AZIBs.展开更多
Dynamic thermal mechanical analysis was used to evaluate the viscoelasticity of asphalt.The parameters included the energy storage modulus(E),the loss modulus(E'),and the loss tangent(tanδ).The impact of three ki...Dynamic thermal mechanical analysis was used to evaluate the viscoelasticity of asphalt.The parameters included the energy storage modulus(E),the loss modulus(E'),and the loss tangent(tanδ).The impact of three kinds of particles containing CaCO_(3)with different size and structure on the mechanical properties was also measured.The addition of limestone increases the glass transition temperature,while nanoCaCO_(3)@SiO_(2)decreases the glass transition temperature.Nano-CaCO_(3)has a negligible effect on the glass transition temperature.The particle size of the limestone is 0.075 mm,which is a material at the micrometer level.During the heating process,it hinders the molecular movement and makes the material harder.Thus the glass transition temperature is relatively high.展开更多
Lithium(Li)metal is considered the most promising anode material for the next generation of secondary batteries due to its high theoretical specific capacity and low potential.However,the application of Li anode in re...Lithium(Li)metal is considered the most promising anode material for the next generation of secondary batteries due to its high theoretical specific capacity and low potential.However,the application of Li anode in rechargeable Li metal batteries(LMBs)is hindered due to the short cycle life caused by uncontrolled dendrite growth.In this work,a dendrite-free anode(Li–Sn/Cu)is reinforced synergistically by lithophilic alloy,and a 3D grid structure is designed.Li^(+)diffusion and uniform nucleation are effectively induced by the lithophilic alloy Li_(22)Sn_(5).Moreover,homogeneous deposition of Li^(+)is caused by the reversible gridded Li plating/stripping effect of Cu mesh.Furthermore,the local space electric field is redistributed throughout the 3D conductive network,whereby the tip effect is suppressed,thus inhibiting the growth of Li dendrites.Also,the volume expansion of the anode during cycling is eased by the 3D grid structure.The results show that the Li–Sn/Cu symmetric battery can stably cycle for more than 10,000 h at 2 mA.cm^(-2)and 1 mAh.cm^(-2)with a low overpotential.The capacity retention of the LiFePO_(4)full battery remains above 90.7%after 1,000 cycles at 1C.This work provides a facile,low-cost,and effective strategy for obtaining Li metal batteries with ultra-long cycle life.展开更多
Herein we report novel photocatalysts ZnIn_(2)S_(4)-Ag-LaFeO_(3) with the core-shell structured materials prepared by hydrothermal method.In order to improve the efficiency of photocatalytic degradation of pollutants,...Herein we report novel photocatalysts ZnIn_(2)S_(4)-Ag-LaFeO_(3) with the core-shell structured materials prepared by hydrothermal method.In order to improve the efficiency of photocatalytic degradation of pollutants,LaFeO_(3) was prepared by hydrothermal followed by calcination,and further Ag nanoparticle(NP)was loaded onto the spherical structure of LaFeO_(3) by photolysis of silver nitrate,and finally the spherical Znln_(2)S_(4)-Ag-LaFeO_(3) photocatalyst was prepared by hydrothermal method again.The structure and properties of the as-prepared materials were characterized by X-ray photoelectron spectroscopy,ultraviolet-visible absorption spectroscopy,X-ray diffraction,scanning electron microscopy and fluorescence spectra.The results show that the synthesized composite photocatalysts display a significant improvement in photocatalytic efficiency relative to the single LaFeO_(3) and ZnIn_(2)S_(4)and form a core-shell structure.Furthermore,the effect of the ratio of each component on the photocatalytic efficiency was investigated in detail,and it is discovered that at an Methylene Blue(MB)concentration of 0.219 mol/L,the degradation rate of MB is 95%at 120 min using 0.02 g of catalyst with an ideal ZnIn_(2)S_(4):Ag:LaFeO_(3)ratio of 10:0.5:1.The possible mechanisms to improve the photocatalytic efficiency were explored.展开更多
The infinite-layer nickelates,proposed as analogs to superconducting cuprates,provide a promising platform for exploring the mechanisms of unconventional superconductivity.However,the superconductivity has been exclus...The infinite-layer nickelates,proposed as analogs to superconducting cuprates,provide a promising platform for exploring the mechanisms of unconventional superconductivity.However,the superconductivity has been exclusively observed in thin films under atmospheric pressure,underscoring the critical role of the heterointerface.展开更多
Sc_(2)O_(3),as a host for solid-state laser gain materials,has advantage of high thermal conductivity and easy matching with activating ions,which is promising in high-power laser applications.Currently,Yb-doped Sc_(2...Sc_(2)O_(3),as a host for solid-state laser gain materials,has advantage of high thermal conductivity and easy matching with activating ions,which is promising in high-power laser applications.Currently,Yb-doped Sc_(2)O_(3) ceramics have been fabricated at very high sintering temperatures,but their optical quality and sintering process still need further improvement.In this work,5%Yb:Sc_(2)O_(3)(in mass)nano-powders were obtained by co-precipitation,and then transparent ceramics were fabricated by vacuum pre-sintering and hot isostatic pressing(HIP)post-treatment.The cubic Yb:Sc_(2)O_(3) nano-powders with good dispersity and an average crystallite of 29 nm were obtained.Influence of pre-sintering temperatures(1500-1700℃)on densification process,microstructure changes,and optical transmittance of Yb:Sc_(2)O_(3) ceramics was detected.Experimental data revealed that all samples have a uniform microstructure,while the average grain sizes increase with the increase of the sintering temperatures.Impressively,the optimum in-line transmittance of Yb:Sc_(2)O_(3) ceramics,pre-sintered at 1550℃after HIP post-treatment,reaches 78.1%(theoretical value of 80%)at 1100 nm.Spectroscopic properties of the Yb:Sc_(2)O_(3) ceramics reveal that the minimum population inversion parameterβ2 and the luminescence decay time of 5%Yb:Sc_(2)O_(3) ceramics are 0.041 and 0.49 ms,respectively,which demonstrate that the optical quality of the Yb:Sc_(2)O_(3) has been improved.Meanwhile,their best vacuum sintering temperature can be controlled down to a lower temperature(1550℃).In conclusion,Yb:Sc_(2)O_(3) nano-powders are successfully synthesized by co-precipitation method,and good optical quality transparent ceramics are fabricated by vacuum pre-sintering at 1550℃and HIP post-treatment.展开更多
Structural modification of three dimensional(3D)materials for the application of dielectric loss-based microwave absorbing materials(MAMs)usually relies on intricate synthesis process and can pose challenges in terms ...Structural modification of three dimensional(3D)materials for the application of dielectric loss-based microwave absorbing materials(MAMs)usually relies on intricate synthesis process and can pose challenges in terms of scalability and mass production for practical application.In this work,we reported a successful attempt in modifying the 3D structure of mesoporous lanthanum oxide(La_(2)O_(3))for effective broadband MAMs candidate via simple co-precipitation process.The inclusion of cetyltrimethylammonium bromide(CTAB)and hydrothermal aging treatment result in a significant transformation of La_(2)O_(3)particles from their original polygonal form to a 3D coral-like and nano needle-like structure.The utilization of CTAB and hydrothermal aging results in the increase of surface area and a two-fold increase in pore volume of the resulting La_(2)O_(3).Due to its unique 3D structure,the 3D coral-like and nano needle-like La_(2)O_(3)materials possess a broadband electromagnetic(EM)wave absorption characteristic with the effective absorption bandwidth(EAB)covering the C-band frequency range.Specifically,in the La_(2)O_(3)C-H sample(with CTAB-with hydrothermal),it exhibits strong EM wave absorption with a reflection loss(RL)value of-33.07 dB which equals to 99.95%EM wave absorption at a thickness of only 1.50 mm.The detailed analysis of EM wave absorption properties reveals that the improvement of La_(2)O_(3)materials to attenuate EM wave energy arises from the dielectric loss phenomenon,the enhanced interfacial polarization,multiple reflections mechanism,and conduction loss mechanism induced by the 3D structural formation of the La_(2)O_(3)structure.This work proposes a novel and efficient approach in synthesizing and modifying 3D materials for effective broadband EM wave absorption.展开更多
The wide band gap characteristics of gallium oxide make it very suitable for the preparation of solar-blind ultra-violet photodetectors.The responsivity of ultraviolet photodetectors based on thin films is often low.H...The wide band gap characteristics of gallium oxide make it very suitable for the preparation of solar-blind ultra-violet photodetectors.The responsivity of ultraviolet photodetectors based on thin films is often low.However,nanomaterials have excellent photoelectric properties in device applications due to the high stability brought by high specific surface area and high crystal quality.Here,we successfully depositedβ-Ga_(2)O_(3) nanopores on the double-pass ordered porous AAO tem-plate by PLD.The porous AAO template is used as the growth space of nanomaterials,and the gallium oxide material is filled into the pores of the template to form a nanotube structure.By optimizing the preparation process,the relationship be-tween the performance of gallium oxide nanopores and the growth time was studied in depth.With the increase of growth time,the responsivity of the detector was improved.The rise timeτr=0.7 s,the decay timeτ_(d)=1.3 s,and the responsivity reached 4.63 mA·W^(-1),which was higher than 2.24 mA·W^(-1)of the responsivity of silicon-based gallium oxide nanorods.展开更多
基金supported by the National Key Research and Development Program of China(No.2023YFB3812200)the Natural Science Foundation of China(No.52472135)+1 种基金Center for International Cooperation and Disciplinary Innovation(111 Center,No.B23016)Guangdong Basic and Applied Basic Research Foundation(No.2022B1515120041)。
文摘Four groups of nano barium titanate powders were prepared using the hydrothermal method.Their phase structure,microscopic morphology and electrical properties were investigated,and the impacts of raw materials on the barium titanate powders as well as the reaction mechanisms were explored.XRD and FTIR indicate the presence of hydroxyl groups and a small amount of carboxyl groups on the powder surface,and the choice of raw materials significantly affects phase purity,with H_(2)TiO_(3)as raw materials being prone to introducing impurity phases.SEM shows that different precursors lead to morphological differences:soluble raw materials form uniform nanoparticles through a"dissolution-precipitation"mechanism while using TiO_(2)as the titanium source generates hollow bowl-like structures through an"in-situ transformation"mechanism,attributed to the synergistic effects of Ostwald ripening and Kirkendall diffusion.The dielectric properties tests indicate that the dielectric constant at room temperature(1500-3000)and Curie temperature(2000-5000)of the ceramics are both lower than those of ceramics produced by solid-state methods(4000-6000 and>10000),and the phase transition temperature range is widened,which is attributed to factors such as grain refinement,reduced tetragonality,grain boundary effects,and increased defects.
基金Supported by the Science and Technology Cooperation and Exchange special project of Cooperation of Shanxi Province(202404041101014)the Fundamental Research Program of Shanxi Province(202403021212333)+3 种基金the Joint Funds of the National Natural Science Foundation of China(U24A20555)the Lvliang Key R&D of University-Local Cooperation(2023XDHZ10)the Initiation Fund for Doctoral Research of Taiyuan University of Science and Technology(20242026)the Outstanding Doctor Funding Award of Shanxi Province(20242080).
文摘To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced.
基金Supported by the National Key Research and Development Program of Traditional Chinese Medicine Modernization Project,China(No.2023YFC3504000)the Science and Technology Development Project of Jilin Province,China(No.20240404043ZP)the Science and Technology Innovation Cooperation Project of Changchun Science and Technology Bureau and Chinese Academy of Sciences,China(No.23SH14)。
文摘In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs.
基金Supported by the National Key Research Program(No.2024-1129-954-112)National Natural Science Foundation of China(No.52372033)Guangxi Science and Technology Major Program(No.AA24263054)。
文摘Alkali-free SiO_(2)-Al_(2)O_(3)-CaO-MgO with different SiO_(2)/Al_(2)O_(3)mass ratios was prepared by conventional melt quenching method.The glass network structure,thermodynamic properties and elastic modulus changes with SiO_(2)and Al_(2)O_(3)ratios were investigated using various techniques.It is found that when SiO_(2)is replaced by Al_(2)O_(3),the Q^(4) to Q^(3) transition of silicon-oxygen network decreases while the aluminum-oxygen network increases,which result in the transformation of Si-O-Si bonds to Si-O-Al bonds and an increase in glass network connectivity even though the intermolecular bond strength decreases.The glass transition temperature(T_(g))increases continuously,while the thermal expansion coefficient increases and high-temperature viscosity first decreases and then increases.Meanwhile,the elastic modulus values increase from 93 to 102 GPa.This indicates that the elastic modulus is mainly affected by packing factor and dissociation energy,and elements with higher packing factors and dissociation energies supplant those with lower values,resulting in increased rigidity within the glass.
基金supported by National Natural Science Foundation of China(No.52025055 and 52275571)Basic Research Operation Fund of China(No.xzy012024024).
文摘Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is proposed.The electric field applied between the template and the substrate drives the contact,tilting,filling,and holding processes.By accurately controlling the introduced included angle between the flexible template and the substrate,tilted nanostructures with a controllable angle are imprinted onto the substrate,although they are vertical on the template.By flexibly adjusting the electric field intensity and the included angle,large-area uniform-tilted,gradient-tilted,and high-angle-tilted nanostructures are fabricated.In contrast to traditional replication,the morphology of the nanoimprinting structure is extended to customized control.This work provides a cost-effective,efficient,and versatile technology for the fabrication of various large-area tilted metasurface structures.As an illustration,a tilted nanograting with a high coupling efficiency is fabricated and integrated into augmented reality displays,demonstrating superior imaging quality.
基金supported by the National Key R&D Program of China(No.2021YFB3501102).
文摘Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspheres.And modification of the pore structure is one of the effective strategies.In this study,multi-cavity mesoporous carbon microspheres were successfully synthesized by the synergistic method of soft and hard templates,during which a phenolic resin with superior thermal stability was employed as the carbon precursor and a mixture of silica sol and F108 as the mesoporous template.Carbon microspheres with multi-cavity mesoporous structures were prepared,and all the samples showed highly even mesopores,with diameters around 12 nm.The diameter of these microspheres decreased from 396.8 nm to about 182.5 nm with the increase of silica sol.After CO_(2) activation,these novel carbon microspheres(APCF0.5-S1.75)demonstrated high specific surface area(983.3 m^(2)/g)and remarkable CO_(2) uptake of 4.93 mmol/g at 0℃ and1 bar.This could be attributed to the unique multi-cavity structure,which offers uniform mesoporous pore channels,minimal CO_(2) transport of and a greater number of active sites for CO_(2) adsorption.
基金supported by the Natural Science Foundation of China(Nos.52125202,52202100,and U24A2065)the Natural Science Foundation of Jiangsu Province(BK20243016)Fundamental Research Funds for the Central Universities,China Postdoctoral Science Foundation(No.2024T171166).
文摘Aqueous zinc-ion batteries(AZIBs)have garnered considerable attention as promising post-lithium energy storage technologies owing to their intrinsic safety,cost-effectiveness,and competitive gravimetric energy density.However,their practical commercialization is hindered by critical challenges on the anode side,including dendrite growth and parasitic reactions at the anode/electrolyte interface.Recent studies highlight that rational electrolyte structure engineering offers an effective route to mitigate these issues and strengthen the electrochemical performance of the zinc metal anode.In this review,we systematically summarize state-of-the-art strategies for electrolyte optimization,with a particular focus on the zinc salts regulation,electrolyte additives,and the construction of novel electrolytes,while elucidating the underlying design principles.We further discuss the key structure–property relationships governing electrolyte behavior to provide guidance for the development of next-generation electrolytes.Finally,future perspectives on advanced electrolyte design are proposed.This review aims to serve as a comprehensive reference for researchers exploring high-performance electrolyte engineering in AZIBs.
基金Funded by National Natural Science Foundation of China(No.52472033)。
文摘Dynamic thermal mechanical analysis was used to evaluate the viscoelasticity of asphalt.The parameters included the energy storage modulus(E),the loss modulus(E'),and the loss tangent(tanδ).The impact of three kinds of particles containing CaCO_(3)with different size and structure on the mechanical properties was also measured.The addition of limestone increases the glass transition temperature,while nanoCaCO_(3)@SiO_(2)decreases the glass transition temperature.Nano-CaCO_(3)has a negligible effect on the glass transition temperature.The particle size of the limestone is 0.075 mm,which is a material at the micrometer level.During the heating process,it hinders the molecular movement and makes the material harder.Thus the glass transition temperature is relatively high.
基金supported by the National Natural Science Foundation of China(No.52401221)Shandong Provincial Natural Science Foundation,China(No.ZR2022QE014)+1 种基金the Basic Scientific Research Fund for Central Universities(No.202112018)the Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)。
文摘Lithium(Li)metal is considered the most promising anode material for the next generation of secondary batteries due to its high theoretical specific capacity and low potential.However,the application of Li anode in rechargeable Li metal batteries(LMBs)is hindered due to the short cycle life caused by uncontrolled dendrite growth.In this work,a dendrite-free anode(Li–Sn/Cu)is reinforced synergistically by lithophilic alloy,and a 3D grid structure is designed.Li^(+)diffusion and uniform nucleation are effectively induced by the lithophilic alloy Li_(22)Sn_(5).Moreover,homogeneous deposition of Li^(+)is caused by the reversible gridded Li plating/stripping effect of Cu mesh.Furthermore,the local space electric field is redistributed throughout the 3D conductive network,whereby the tip effect is suppressed,thus inhibiting the growth of Li dendrites.Also,the volume expansion of the anode during cycling is eased by the 3D grid structure.The results show that the Li–Sn/Cu symmetric battery can stably cycle for more than 10,000 h at 2 mA.cm^(-2)and 1 mAh.cm^(-2)with a low overpotential.The capacity retention of the LiFePO_(4)full battery remains above 90.7%after 1,000 cycles at 1C.This work provides a facile,low-cost,and effective strategy for obtaining Li metal batteries with ultra-long cycle life.
基金Project supported by the National Natural Science Foundation of China(21101107,51173107)State Key Laboratory of Pollution Control and Resource Reuse Foundation(PCRRF19017)。
文摘Herein we report novel photocatalysts ZnIn_(2)S_(4)-Ag-LaFeO_(3) with the core-shell structured materials prepared by hydrothermal method.In order to improve the efficiency of photocatalytic degradation of pollutants,LaFeO_(3) was prepared by hydrothermal followed by calcination,and further Ag nanoparticle(NP)was loaded onto the spherical structure of LaFeO_(3) by photolysis of silver nitrate,and finally the spherical Znln_(2)S_(4)-Ag-LaFeO_(3) photocatalyst was prepared by hydrothermal method again.The structure and properties of the as-prepared materials were characterized by X-ray photoelectron spectroscopy,ultraviolet-visible absorption spectroscopy,X-ray diffraction,scanning electron microscopy and fluorescence spectra.The results show that the synthesized composite photocatalysts display a significant improvement in photocatalytic efficiency relative to the single LaFeO_(3) and ZnIn_(2)S_(4)and form a core-shell structure.Furthermore,the effect of the ratio of each component on the photocatalytic efficiency was investigated in detail,and it is discovered that at an Methylene Blue(MB)concentration of 0.219 mol/L,the degradation rate of MB is 95%at 120 min using 0.02 g of catalyst with an ideal ZnIn_(2)S_(4):Ag:LaFeO_(3)ratio of 10:0.5:1.The possible mechanisms to improve the photocatalytic efficiency were explored.
基金supported by the National Natural Science Foundation of China[52125307(to P.G.),12404192(to R.C.S),12274061(to L.Q.)]Key Research and Development Program from the Ministry of Science and Technology(2023YFA1406301)the support from the New Cornerstone Science Foundation through the XPLORER PRIZE。
文摘The infinite-layer nickelates,proposed as analogs to superconducting cuprates,provide a promising platform for exploring the mechanisms of unconventional superconductivity.However,the superconductivity has been exclusively observed in thin films under atmospheric pressure,underscoring the critical role of the heterointerface.
基金National Key R&D Program of China(2023YFE3812005)International Partnership Program of Chinese Academy of Sciences(121631KYSB20200039)+1 种基金National Center for Research and Development(WPC2/1/SCAPOL/2021)Chinese Academy of Sciences President’s International Fellowship Initiative(2024VEA0005,2024VEA0014)。
文摘Sc_(2)O_(3),as a host for solid-state laser gain materials,has advantage of high thermal conductivity and easy matching with activating ions,which is promising in high-power laser applications.Currently,Yb-doped Sc_(2)O_(3) ceramics have been fabricated at very high sintering temperatures,but their optical quality and sintering process still need further improvement.In this work,5%Yb:Sc_(2)O_(3)(in mass)nano-powders were obtained by co-precipitation,and then transparent ceramics were fabricated by vacuum pre-sintering and hot isostatic pressing(HIP)post-treatment.The cubic Yb:Sc_(2)O_(3) nano-powders with good dispersity and an average crystallite of 29 nm were obtained.Influence of pre-sintering temperatures(1500-1700℃)on densification process,microstructure changes,and optical transmittance of Yb:Sc_(2)O_(3) ceramics was detected.Experimental data revealed that all samples have a uniform microstructure,while the average grain sizes increase with the increase of the sintering temperatures.Impressively,the optimum in-line transmittance of Yb:Sc_(2)O_(3) ceramics,pre-sintered at 1550℃after HIP post-treatment,reaches 78.1%(theoretical value of 80%)at 1100 nm.Spectroscopic properties of the Yb:Sc_(2)O_(3) ceramics reveal that the minimum population inversion parameterβ2 and the luminescence decay time of 5%Yb:Sc_(2)O_(3) ceramics are 0.041 and 0.49 ms,respectively,which demonstrate that the optical quality of the Yb:Sc_(2)O_(3) has been improved.Meanwhile,their best vacuum sintering temperature can be controlled down to a lower temperature(1550℃).In conclusion,Yb:Sc_(2)O_(3) nano-powders are successfully synthesized by co-precipitation method,and good optical quality transparent ceramics are fabricated by vacuum pre-sintering at 1550℃and HIP post-treatment.
基金Project supported by National Research and Innovation Agency through Rumah Program Organisasi Riset Nanoteknologi dan Material Maj u(ORNM)2024Indonesia Ministry of Finance through the competitive research program of RISPRO Kompetisi(PRJ-68/LPDP/2023)。
文摘Structural modification of three dimensional(3D)materials for the application of dielectric loss-based microwave absorbing materials(MAMs)usually relies on intricate synthesis process and can pose challenges in terms of scalability and mass production for practical application.In this work,we reported a successful attempt in modifying the 3D structure of mesoporous lanthanum oxide(La_(2)O_(3))for effective broadband MAMs candidate via simple co-precipitation process.The inclusion of cetyltrimethylammonium bromide(CTAB)and hydrothermal aging treatment result in a significant transformation of La_(2)O_(3)particles from their original polygonal form to a 3D coral-like and nano needle-like structure.The utilization of CTAB and hydrothermal aging results in the increase of surface area and a two-fold increase in pore volume of the resulting La_(2)O_(3).Due to its unique 3D structure,the 3D coral-like and nano needle-like La_(2)O_(3)materials possess a broadband electromagnetic(EM)wave absorption characteristic with the effective absorption bandwidth(EAB)covering the C-band frequency range.Specifically,in the La_(2)O_(3)C-H sample(with CTAB-with hydrothermal),it exhibits strong EM wave absorption with a reflection loss(RL)value of-33.07 dB which equals to 99.95%EM wave absorption at a thickness of only 1.50 mm.The detailed analysis of EM wave absorption properties reveals that the improvement of La_(2)O_(3)materials to attenuate EM wave energy arises from the dielectric loss phenomenon,the enhanced interfacial polarization,multiple reflections mechanism,and conduction loss mechanism induced by the 3D structural formation of the La_(2)O_(3)structure.This work proposes a novel and efficient approach in synthesizing and modifying 3D materials for effective broadband EM wave absorption.
文摘The wide band gap characteristics of gallium oxide make it very suitable for the preparation of solar-blind ultra-violet photodetectors.The responsivity of ultraviolet photodetectors based on thin films is often low.However,nanomaterials have excellent photoelectric properties in device applications due to the high stability brought by high specific surface area and high crystal quality.Here,we successfully depositedβ-Ga_(2)O_(3) nanopores on the double-pass ordered porous AAO tem-plate by PLD.The porous AAO template is used as the growth space of nanomaterials,and the gallium oxide material is filled into the pores of the template to form a nanotube structure.By optimizing the preparation process,the relationship be-tween the performance of gallium oxide nanopores and the growth time was studied in depth.With the increase of growth time,the responsivity of the detector was improved.The rise timeτr=0.7 s,the decay timeτ_(d)=1.3 s,and the responsivity reached 4.63 mA·W^(-1),which was higher than 2.24 mA·W^(-1)of the responsivity of silicon-based gallium oxide nanorods.