With the increasing complexity of the current electromagnetic environment,excessive microwave radi-ation not only does harm to human health but also forms various electromagnetic interference to so-phisticated electro...With the increasing complexity of the current electromagnetic environment,excessive microwave radi-ation not only does harm to human health but also forms various electromagnetic interference to so-phisticated electronic instruments.Therefore,the design and preparation of electromagnetic absorbing composites represent an efficient approach to mitigate the current hazards of electromagnetic radiation.However,traditional electromagnetic absorbers are difficult to satisfy the demands of actual utilization in the face of new challenges,and emerging absorbents have garnered increasing attention due to their structure and performance-based advantages.In this review,several emerging composites of Mxene-based,biochar-based,chiral,and heat-resisting are discussed in detail,including their synthetic strategy,structural superiority and regulation method,and final optimization of electromagnetic absorption ca-pacity.These insights provide a comprehensive reference for the future development of new-generation electromagnetic-wave absorption composites.Moreover,the potential development directions of these emerging absorbers have been proposed as well.展开更多
To advance the precise regulation and high-value utilization of halloysite nanotubes(HNTs),this work systematically investigated five treatment strategies,including calcination,acid treatment,alkali treatment,acid tre...To advance the precise regulation and high-value utilization of halloysite nanotubes(HNTs),this work systematically investigated five treatment strategies,including calcination,acid treatment,alkali treatment,acid treatment of calcined HNTs,and alkali treatment of calcined HNTs,to modulate their structural and application properties.The structural characteristics,surface properties,and methylene blue(MB)adsorption capacity of HNTs under multiple treatments were systematically analyzed.Calcination at varying temperatures modified the crystal structure,morphology,and surface properties of HNTs,with higher calcination temperatures reducing their reactivity towards MB.Moderate acid treatment expanded the lumen and decreased the surface potential of HNTs,significantly enhancing MB adsorption capacity.In contrast,alkali treatment dispersed the multilayered walls of HNTs and raised surface potential,reducing MB affinity.Acid treatment of calcined HNTs effectively increased their specific surface areas by leaching most of Al while maintaining the tubular structure,thereby maximizing MB adsorption.Alkali treatment of calcined HNTs destroyed the tubular structure and resulted in poor MB adsorption.HNTs pre-calcined at 600℃ for 3 h and acid-treated at 60℃ for 8 h exhibited an optimal specific surface area of443 m^(2)·g^(-1)and an MB adsorption capacity of 190 mg·g^(-1).Kinetic and Arrhenius equation fittings indicated that chemical reactions control interactions of acids and alkalis with HNTs.This study provides a comprehensive comparison and analysis of five treatment methods,offering insights into regulating the structures and surface properties of HNTs by controlling the treatment condition,thereby laying a foundation for their efficient utilization in practical applications.展开更多
Lithium halide solid-state electrolytes,with the general formula of Li_(3±m)M_(n)X_(6),are regarded as the promising families of electrolyte material for all solid-state lithium-ion batteries because of the relat...Lithium halide solid-state electrolytes,with the general formula of Li_(3±m)M_(n)X_(6),are regarded as the promising families of electrolyte material for all solid-state lithium-ion batteries because of the relatively good ionic conductivity,high oxidative stability against high-voltage oxide cathodes,and broad electrochemical stability window[1].Here,M stands for one or multiple metal elements and X for one or multiple halogen elements.展开更多
In response to the limitations of conventional chemical synthesis methods for the structural modulation of nanomaterials,an innovative high magnetic field-assisted wet chemical synthesis method was proposed to prepare...In response to the limitations of conventional chemical synthesis methods for the structural modulation of nanomaterials,an innovative high magnetic field-assisted wet chemical synthesis method was proposed to prepare NiFe_(2)O_(4)/Fe_(2)O_(3) heterostructures.It is found that the high-energy physical field could induce a more homogeneous morphology of NiFe_(2)O_(4)/Fe_(2)O_(3),accompanied by phase transformation from Fe_(2)O_(3) to NiFe_(2)O_(4).As a result,the optimized structure obtained under the magnetic field endows NiFe_(2)O_(4)/Fe_(2)O_(3) with enhanced performance for the lithium-ion battery anode,as evidenced by an increase of 16%(1200 mA·h/g)in discharge capacity and 24% in ultra-stable cycling performance(capacity retention of 97.1%).These results highlight the feasibility of high magnetic fields in modulating material structure and enhancing lithium storage performance.展开更多
Room-temperature sodium-sulfur(RT Na-S)batteries have been regarded as promising energy storage technologies in grid-scale stationary energy storage systems due to their low cost,natural abundance,and high-energy dens...Room-temperature sodium-sulfur(RT Na-S)batteries have been regarded as promising energy storage technologies in grid-scale stationary energy storage systems due to their low cost,natural abundance,and high-energy density.However,the practical application of RT Na-S batteries is hindered by low reversible capacity and unsatisfying long-cycling performance arising from the severe shuttle effect and sluggish S redox kinetics.This review provides an overview of recent efforts for the optimization strategies of the electronic structure of catalysts via catalyst engineering to enhance the adsorption and catalytic activity toward soluble long-chain sodium polysulfides(NaPSs).Finally,the current challenges and prospects for further optimization strategies of catalysts,understanding catalysis and structural evolution mechanism,and achieving practical applications are highlighted to meet the commercial requirements of RT Na-S batteries.展开更多
By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variationa...By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variational Zn-salen ligands RZn and NADH(reduced nicotinamide adenine dinucleotide)mimic modified tridentate ligands with square-planar Pd ions.UV-Vis and luminescence spectra experiments reveal that different anions could selec-tively interact with different sites of Zn-salen modified metal-organic cages to achieve the structural regulation of cage compound,by using the differentiated host-vip electrostatic interactions of counter ions with metal-organic hosts.Compared to other anions,the presence of chloride ions caused the most significant fluorescence emission enhancement of Pd‑R(Zn),meanwhile,the UV-Vis absorption band attributed to the salen aromatic backbone showed an absorption decrease,and the metal-to-ligand induced peak displayed a blue shift effect.Circular dichro-ism and ^(1)H NMR spectra further demonstrate that the introduction of chloride anions is beneficial to keeping a more rigid scaffold.展开更多
The stability and electrocatalytic efficiency of transition metal oxides for water splitting is determined by geometric and electronic structure,especially under high current densities.Herein,a newly designed lamella-...The stability and electrocatalytic efficiency of transition metal oxides for water splitting is determined by geometric and electronic structure,especially under high current densities.Herein,a newly designed lamella-heterostructured nanoporous CoFe/CoFe_(2)O_(4) and CeO_(2−x),in situ grown on nickel foam(NF),holds great promise as a high-efficient bifunctional electrocatalyst(named R-CoFe/Ce/NF)for water splitting.Experimental characterization verifies surface reconstruction from CoFe alloy/oxide to highly active CoFeOOH during in situ electrochemical polarization.By virtues of three-dimensional nanoporous architecture and abundant electroactive CoFeOOH/CeO_(2−x) heterostructure interfaces,the R-CoFe/Ce/NF electrode achieves low overpotentials for oxygen evolution(η_(10)=227 mV;η_(500)=450 mV)and hydrogen evolution(η_(10)=35 mV;η_(408)=560 mV)reactions with high normalized electrochemical active surface areas,respectively.Additionally,the alkaline full water splitting electrolyzer of R-CoFe/Ce/NF||R-CoFe/Ce/NF achieves a current density of 50 mA·cm^(−2) only at 1.75 V;the decline of activity is satisfactory after 100-h durability test at 300 mA·cm^(−2).Density functional theory also demonstrates that the electron can transfer from CeO_(2−x) by virtue of O atom to CoFeOOH at CoFeOOH/CeO_(2−x) heterointerfaces and enhancing the adsorption of reactant,thus optimizing electronic structure and Gibbs free energies for the improvement of the activity for water splitting.展开更多
Structural regulation of Pd-based electrocatalytic hydrodechlorination(EHDC)catalyst for constructing high-efficient cathode materials with low noble metal content and high atom utilization is crucial but still challe...Structural regulation of Pd-based electrocatalytic hydrodechlorination(EHDC)catalyst for constructing high-efficient cathode materials with low noble metal content and high atom utilization is crucial but still challenging.Herein,a support electron inductive effect of Pd-Mn/Ni foam catalyst was proposed via in-situ Mn doping to optimize the electronic structure of the Ni foam(NF),which can inductive regulation of Pd for improving the EHDC performance.The mass activity and current efficiency of Pd-Mn/NF catalyst are 2.91 and 1.34 times superior to that of Pd/NF with 2,4-dichlorophenol as model compound,respectively.The Mn-doped interlayer optimized the electronic structure of Pd by bringing the d-state closer to the Fermi level than Pd on the NF surface,which optimizied the binding of EHDC intermediates.Additionally,the Mn-doped interlayer acted as a promoter for generating H∗and accelerating the EHDC reaction.This work presents a simple and effective regulation strategy for constructing high-efficient cathode catalyst for the EHDC of chlorinated organic compounds.展开更多
Smart batteries play a key role in upgrading energy storage systems.However,they require a well-balanced integration of material structure,functional properties,and electrochemical performance,and their development is...Smart batteries play a key role in upgrading energy storage systems.However,they require a well-balanced integration of material structure,functional properties,and electrochemical performance,and their development is limited by conventional material systems in terms of energy density,response time,and functional integration.Carbon materials have emerged as a key solution for overcoming these problems due to their structural adjustability and multifunctional compatibility.Strategies for improving their electrochemical performance by changing the pore structure and interlayer spacing,as well as chemical functionalization,and composite design are analyzed,and their impact on improving the specific capacity and cycling stability of batteries is demonstrated.The unique advantages of carbon materials in realizing smart functions such as power supply,real-time monitoring and energy management in smart batteries are also discussed.Based on current progress in related fields,the prospects for the use of carbon materials in smart batteries are evaluated.展开更多
Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type...Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type secondary batter-ies,DIBs perform a unique working mechanism,which employ both cation and anion taking part in capacity contribution at an anode and a cathode,respectively,during electrochemical reactions.Graphite has been identified as a suitable cathode material for anion intercalation at high voltages(>4.8 V)with fast reaction kinetics.However,the development of DIBs is being hindered by dynamic mismatch between a cathode and an anode due to sluggish Li+diffusion at a high rate.Herein,we prepared phyllostachys edulis derived carbon(PEC)through microstructure regulation strategy and investigated the carbonized temperature effect,which effectively tailored the rich short-range ordered graphite microdomains and disor-dered amorphous regions,as well as a unique nano-pore hierarchical structure.The pore size distribution of nano-pores was concentrated in 0.5-5 nm,providing suitable channels for rapid Li+transportation.It was found that PEC-500(carbon-ized at 500℃)achieved a high capacity of 436 mAh·g^(-1)at 300 mA·g^(-1)and excellent rate performance(maintaining a high capacity of 231 mAh·g^(-1)at 3 A·g^(-1)).The assembled dual-carbon PEC-500||graphite full battery delivered 114 mAh·g^(-1)at 10 C with 96%capacity retention after 3000 cycles and outstanding rate capability,providing 74 mAh·g^(-1)at 50 C.展开更多
Biomass-derived hard carbons,usually prepared by pyrolysis,are widely considered the most promising anode materials for sodium-ion bat-teries(SIBs)due to their high capacity,low poten-tial,sustainability,cost-effectiv...Biomass-derived hard carbons,usually prepared by pyrolysis,are widely considered the most promising anode materials for sodium-ion bat-teries(SIBs)due to their high capacity,low poten-tial,sustainability,cost-effectiveness,and environ-mental friendliness.The pyrolysis method affects the microstructure of the material,and ultimately its so-dium storage performance.Our previous work has shown that pyrolysis in a sealed graphite vessel im-proved the sodium storage performance of the car-bon,however the changes in its microstructure and the way this influences the sodium storage are still unclear.A series of hard carbon materials derived from corncobs(CCG-T,where T is the pyrolysis temperature)were pyrolyzed in a sealed graphite vessel at different temperatures.As the pyrolysis temperature increased from 1000 to 1400℃ small carbon domains gradually transformed into long and curved domains.At the same time,a greater number of large open pores with uniform apertures,as well as more closed pores,were formed.With the further increase of pyrolysis temperature to 1600℃,the long and curved domains became longer and straighter,and some closed pores gradually became open.CCG-1400,with abundant closed pores,had a superior SIB performance,with an initial reversible ca-pacity of 320.73 mAh g^(-1) at a current density of 30 mA g^(-1),an initial Coulomb efficiency(ICE)of 84.34%,and a capacity re-tention of 96.70%after 100 cycles.This study provides a method for the precise regulation of the microcrystalline and pore structures of hard carbon materials.展开更多
Two-dimensional(2D) nanomaterials have always been regarded as having great development potential in the field of oil-based lubrication due to their designable structures,functional groups,and abundant active sites.Ho...Two-dimensional(2D) nanomaterials have always been regarded as having great development potential in the field of oil-based lubrication due to their designable structures,functional groups,and abundant active sites.However,understanding the structure-performance relationship between the chemical structure of 2D nanomaterials and their lubrication performance from a comprehensive perspective is crucial for guiding their future development.This review provides a timely and comprehensive overview of the applications of 2D nanomaterials in oil-based lubrication.First,the bottlenecks and mechanisms of action of 2D nanomaterials are outlined,including adsorption protective films,charge adsorption effects,tribochemical reaction films,interlayer slip,and synergistic effects.On this basis,the review summarizes recent structural regulation strategies for 2D nanomaterials,including doping engineering,surface modification,structural optimization,and interfacial mixing engineering.Then,the focus was on analyzing the structure-performance relationship between the chemical structure of 2D nanomaterials and their lubrication performance.The effects of thickness,number of layers,sheet diameter,interlayer spacing,Moiré patterns,wettability,functional groups,concentration,as well as interfacial compatibility and dispersion behavior of 2D nanomaterials were systematically investigated in oil-based lubrication,with the intrinsic correlations resolved through computational simulations.Finally,the review offers a preliminary summary of the significant challenges and future directions for 2D nanomaterials in oil-based lubrication.This review aims to provide valuable insights and development strategies for the rational design of high-performance oil-based lubrication materials.展开更多
Exploring efficient transition-metal-based electrocatalysts is critical for the wide application of electrochemical hydrogen generation technology.Although the phase displays prominent influence on their performance,i...Exploring efficient transition-metal-based electrocatalysts is critical for the wide application of electrochemical hydrogen generation technology.Although the phase displays prominent influence on their performance,it remains a major challenge to achieve phase regulation in the same synthesis method and elucidate the intrinsic relationship between the phase and activity.Herein,we developed a sulfur induced electrodeposition strategy to achieve the precise phase regulation of nickel-based materials from Ni(OH)_(2)to Ni and Ni_(3)S_(2).S atoms can be introduced into Ni and Ni(OH)_(2)due to sulfur inducement,and the S proportion is finely controlled via changing the deposition parameters.Importantly,the obtained S-Ni catalyst displays enhanced hydrogen evolution activity with an ultralow overpotential of 27 mV at 10 mA cm^(-2),which is superior to the S-Ni(OH)_(2),Ni_(3)S_(2),and even Pt/C.Density functional theory(DFT)calculations disclose the S-Ni catalyst exhibits optimal charge state and local coordination,remarkably optimizing the water adsorption and Ni-H^(*)binding energy.This work provides new insights into phase regulation in electrodeposition and an understanding of the intrinsic relationship between phase and activity.展开更多
Nickel(Ni)-rich layered oxides have drawn great attention as cathode for lithium batteries due to their high capacity,high working voltage and competitive cost.Unfortunately,the operation of Ni-rich cathodes suffers f...Nickel(Ni)-rich layered oxides have drawn great attention as cathode for lithium batteries due to their high capacity,high working voltage and competitive cost.Unfortunately,the operation of Ni-rich cathodes suffers from the notorious structural degradation and interfacial side reactions with electrolytes and thus incurs premature failure,especially at high charge cut-off voltages(≥4.4 V).For this,various structural and interphase regulation strategies(such as coating modification,element doping,and electrolyte engineering)are developed to enhance the cycling survivability of Ni-rich cathodes.Among them,electrolyte engineering by changing solvation structure and introducing additives has been considered an efficient method for constructing robust cathode-electrolyte interphases(CEI),inhibiting the formation of harmful species(such as HF and H_(2)O)or restraining the dissolution of transition metal ions.However,there is still an absence of systematic guidelines for selecting and designing competitive electrolyte systems for Ni-rich layered cathodes.In this review,we comprehensively summarize the recent research progress on electrolyte engineering for Ni-rich layered cathodes according to their working mechanisms.Moreover,we propose future perspectives of improving the electrolyte performance,which will provide new insights for designing novel electrolytes toward high-performance Ni-rich layered cathodes.展开更多
Urea-assisted water electrolysis offers a promising route to reduce energy consumption for hydrogen production and meanwhile treat urea-rich wastewater.Herein,we devised a shear force-involved polyoxometalate-organic ...Urea-assisted water electrolysis offers a promising route to reduce energy consumption for hydrogen production and meanwhile treat urea-rich wastewater.Herein,we devised a shear force-involved polyoxometalate-organic supramolecular self-assembly strategy to fabricate 3D hierarchical porous nanoribbon assembly Mn-VN cardoons.A bimetallic polyoxovanadate(POV)with the inherent structural feature of Mn surrounded by[VO_(6)]octahedrons was introduced to trigger precise Mn incorporation in VN lattice,thereby achieving simultaneous morphology engineering and electronic structure modulation.The lattice contraction of VN caused by Mn incorporation drives electron redistribution.The unique hierarchical architecture with modulated electronic structure that provides more exposed active sites,facilitates mass and charge transfer,and optimizes the associated adsorption behavior.Mn-VN exhibits excellent activity with low overpotentials of 86 m V and 1.346 V at 10 m A/cm^(2)for hydrogen evolution reaction(HER)and urea oxidation reaction(UOR),respectively.Accordingly,in the two-electrode urea-assisted water electrolyzer utilizing Mn-VN as a bifunctional catalyst,hydrogen production can occur at low voltage(1.456 V@10 m A/cm^(2)),which has the advantages of energy saving and competitive durability over traditional water electrolysis.This work provides a simple and mild route to construct nanostructures and modulate electronic structure for designing high-efficiency electrocatalysts.展开更多
Pd catalyst with high activity and selectivity for O_(2)reduction to H_(2)O_(2)is highly desirable.However,metallic Pd catalyst suffers from limited activity and selectivity in H_(2)O_(2)photosynthesis due to intrinsi...Pd catalyst with high activity and selectivity for O_(2)reduction to H_(2)O_(2)is highly desirable.However,metallic Pd catalyst suffers from limited activity and selectivity in H_(2)O_(2)photosynthesis due to intrinsically strong O_(2)adsorption at Pd atom sites.Herein,a strategy is proposed to modulate the electronic structure,aiming to weaken O_(2)adsorption and further enhance O_(2)-reduction selectivity through the creation of highly dispersed and electron-enriched Pd^(δ-)atom sites.To achieve this,a novel photochemical plating approach is employed to selectively grow vertical Bi nanosheets on the(010)facet of BiVO_(4).This process confines highly dispersed Pd atoms within the Bi nanosheets,forming a PdBi cocatalyst that significantly boosts H_(2)O_(2)photosynthesis.Notably,the optimized PdBi/BiVO_(4)photocatalyst achieves a high H_(2)O_(2)production concentration of 2246.43μmol L−1,with an apparent quantum efficiency(AQE)of 11.16%,realizing a 1.74-fold enhancement in activity compared to Pd/BiVO_(4)(1289.28μmol L^(−1)).Theoretical calculation and experimental results confirm that the vertical-growth Bi nanosheets induce the formation of well-dispersed and electron-enriched Pd^(δ−)atom sites.This accordingly increases the antibonding-orbital occupancy of Pd-O_(ads),thereby weakening O_(2)adsorption and ultimately facilitating selective O_(2)reduction for photocatalytic H_(2)O_(2)production.This rational design of Pd-based catalysts provides a promising strategy for modulating the electronic structure of active atoms to advance artificial photosynthesis.展开更多
The development and utilization of renewable clean energy can effectively solve the two major problems of energy and environment. As an efficient power generation device that converts hydrogen energy into electric ene...The development and utilization of renewable clean energy can effectively solve the two major problems of energy and environment. As an efficient power generation device that converts hydrogen energy into electric energy, fuel cell has attracted more and more attention. For fuel cells, the oxygen reduction reaction(ORR) at the cathode is the core reaction, and the design and development of high-performance ORR catalysts remain quite challenging. Since the microenvironment of the active center of single atom catalysts(SACs) has an important influence on its catalytic performance, it has been a research focus to improve the ORR activity and stability of electrocatalysts by adjusting the structure of the active center through reasonable structural regulation methods. In this review, we reviewed the preparation and structure–activity relationship of SACs for ORR. Then, the structural precision regulation methods for improving the activity and stability of ORR electrocatalysts are discussed. And the advanced in-situ characterization techniques for revealing the changes of active sites in the electrocatalytic ORR process are summarized. Finally, the challenges and future design directions of SACs for ORR are discussed. This work will provide important reference value for the design and synthesis of SACs with high activity and stability for ORR.展开更多
Poor conductivity and sluggish Na^(+) diffusion kinetic are two major drawbacks for practical application of sodium super-ionic conductor(NASICON) in sodium-ion batteries. In this work, we report a simple approach to ...Poor conductivity and sluggish Na^(+) diffusion kinetic are two major drawbacks for practical application of sodium super-ionic conductor(NASICON) in sodium-ion batteries. In this work, we report a simple approach to synthesize quasi-inverse opal structural NASICON/N-doped carbon for the first time by a delicate one-pot solution-freeze drying-calcination process, aiming at fostering the overall electrochemical performance. Especially, the quasi-inverse opal structural Na_(3)V_(2)(PO_(4))_(3)/N-C(Q-NVP/N-C) displayed continuous pores, which provides interconnected channels for electrolyte permeation and abundant contacting interfaces between electrolyte and materials, resulting in faster kinetics of redox reaction and higher proportion of capacitive behavior.As a cathode material for sodium-ion batteries, the Q-NVP/N-C exhibits high specific capacity of 115 mAh·g^(-1) at 1C, still 61 mAh·g^(-1) at ultra-high current density of 100C,and a specific capacity of 89.7mAh·g^(-1) after 2000 cycles at 20C.This work displays the general validity of preparation method for not only Q-NVP/N-C,but also Na_(3)V_(2)(PO_(4))_(3),which provides a prospect for delicate synthesis of NASICON materials with excellent electrochemical performance.展开更多
Benefiting from the ultrahigh specific surface areas,highly accessible surface atoms,and highly tunable microscopic structures,the two-dimensional metallenes as nanocatalysts have displayed promising performance for v...Benefiting from the ultrahigh specific surface areas,highly accessible surface atoms,and highly tunable microscopic structures,the two-dimensional metallenes as nanocatalysts have displayed promising performance for various electrocatalytic reactions.Herein,we reviewed recent advances on metallenes in structural regulations including defect,phase,strain,interface,doping,and alloying engineering strategies and their applications in energy electrocatalytic reactions involving oxygen reduction reaction,carbon dioxide reduction reaction,hydrogen evolution reaction,and small molecules oxidation reaction.Finally,we proposed the future challenges and directions in this emerging area.展开更多
Based on the overall consideration of individual behaviors of Ricardian and non-Ricardian households, this paper develops a New Keynesian dynamic stochastic general equilibrium(DSGE) model to form a relatively systema...Based on the overall consideration of individual behaviors of Ricardian and non-Ricardian households, this paper develops a New Keynesian dynamic stochastic general equilibrium(DSGE) model to form a relatively systematic research framework for analyzing the economic effects of structural fiscal instruments. Our study findsthat great differences exist in the macroeconomic effects of different fiscal instruments, suggesting that the government should prudently select these fiscal instruments in fiscal macro-control. The simulating results of fiscal shocks show that the effect of tax cut is superior to the effect of increased spending. In the context of slowing economic growth and less potent stimulation policy, the government should transform its previous regulatory approach of fiscal policy and shift from hefty spending stimulus policy to structural tax cuts. This paper believes that China should step up the implementation of public-private partnership, increase its spending on social security, healthcare, pension and public services and facilitate the transition toward a service-based government; and that tax policy should focus on structural tax cuts on consumption to promote the transition of demand structure toward consumption-driven.展开更多
基金supported by the Surface Project of Local De-velopment in Science and Technology Guided by Central Govern-ment(No.2021ZYD0041)the National Natural Science Founda-tion of China(Nos.52377026 and 52301192)+3 种基金the Natural Science Foundation of Shandong Province(No.ZR2019YQ24)the Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)the Special Financial of Shandong Province(Struc-tural Design of High-efficiency Electromagnetic Wave-absorbing Composite Materials and Construction of Shandong Provincial Tal-ent Teams)the“Sanqin Scholars”Innovation Teams Project of Shaanxi Province(Clean Energy Materials and High-Performance Devices Innovation Team of Shaanxi Dongling Smelting Co.,Ltd.).
文摘With the increasing complexity of the current electromagnetic environment,excessive microwave radi-ation not only does harm to human health but also forms various electromagnetic interference to so-phisticated electronic instruments.Therefore,the design and preparation of electromagnetic absorbing composites represent an efficient approach to mitigate the current hazards of electromagnetic radiation.However,traditional electromagnetic absorbers are difficult to satisfy the demands of actual utilization in the face of new challenges,and emerging absorbents have garnered increasing attention due to their structure and performance-based advantages.In this review,several emerging composites of Mxene-based,biochar-based,chiral,and heat-resisting are discussed in detail,including their synthetic strategy,structural superiority and regulation method,and final optimization of electromagnetic absorption ca-pacity.These insights provide a comprehensive reference for the future development of new-generation electromagnetic-wave absorption composites.Moreover,the potential development directions of these emerging absorbers have been proposed as well.
基金Tural Science Foundation of China(No.52274255)the Young Scientists Fund of the National Natural ScienceFoundation of China(No.52404276)+3 种基金Fundamental Re-search Funds for the Central Universities,China(Nos.N2301003,N2201008,N2201004,and N2301025)Liaon-ingRevitalizationTalentsProgram,China(No.XLYC2202028)Postdoctoral Foundation of NortheasternUniversity,Young Elite Scientists Sponsorship Program byChina Association for Science and Technology(No.2022QNRC001)and China Postdoctoral Science Founda-tion(No.2022M720025)。
文摘To advance the precise regulation and high-value utilization of halloysite nanotubes(HNTs),this work systematically investigated five treatment strategies,including calcination,acid treatment,alkali treatment,acid treatment of calcined HNTs,and alkali treatment of calcined HNTs,to modulate their structural and application properties.The structural characteristics,surface properties,and methylene blue(MB)adsorption capacity of HNTs under multiple treatments were systematically analyzed.Calcination at varying temperatures modified the crystal structure,morphology,and surface properties of HNTs,with higher calcination temperatures reducing their reactivity towards MB.Moderate acid treatment expanded the lumen and decreased the surface potential of HNTs,significantly enhancing MB adsorption capacity.In contrast,alkali treatment dispersed the multilayered walls of HNTs and raised surface potential,reducing MB affinity.Acid treatment of calcined HNTs effectively increased their specific surface areas by leaching most of Al while maintaining the tubular structure,thereby maximizing MB adsorption.Alkali treatment of calcined HNTs destroyed the tubular structure and resulted in poor MB adsorption.HNTs pre-calcined at 600℃ for 3 h and acid-treated at 60℃ for 8 h exhibited an optimal specific surface area of443 m^(2)·g^(-1)and an MB adsorption capacity of 190 mg·g^(-1).Kinetic and Arrhenius equation fittings indicated that chemical reactions control interactions of acids and alkalis with HNTs.This study provides a comprehensive comparison and analysis of five treatment methods,offering insights into regulating the structures and surface properties of HNTs by controlling the treatment condition,thereby laying a foundation for their efficient utilization in practical applications.
文摘Lithium halide solid-state electrolytes,with the general formula of Li_(3±m)M_(n)X_(6),are regarded as the promising families of electrolyte material for all solid-state lithium-ion batteries because of the relatively good ionic conductivity,high oxidative stability against high-voltage oxide cathodes,and broad electrochemical stability window[1].Here,M stands for one or multiple metal elements and X for one or multiple halogen elements.
基金supported by the National Natural Science Foundation of China(No.52274294)the Fundamental Research Funds for the Central Universities,China(No.N2124007-1)the Fund of the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University,China(No.SKLSP202101)。
文摘In response to the limitations of conventional chemical synthesis methods for the structural modulation of nanomaterials,an innovative high magnetic field-assisted wet chemical synthesis method was proposed to prepare NiFe_(2)O_(4)/Fe_(2)O_(3) heterostructures.It is found that the high-energy physical field could induce a more homogeneous morphology of NiFe_(2)O_(4)/Fe_(2)O_(3),accompanied by phase transformation from Fe_(2)O_(3) to NiFe_(2)O_(4).As a result,the optimized structure obtained under the magnetic field endows NiFe_(2)O_(4)/Fe_(2)O_(3) with enhanced performance for the lithium-ion battery anode,as evidenced by an increase of 16%(1200 mA·h/g)in discharge capacity and 24% in ultra-stable cycling performance(capacity retention of 97.1%).These results highlight the feasibility of high magnetic fields in modulating material structure and enhancing lithium storage performance.
基金supported by the National Natural Science Foundation of China(No.22005201)the Young Scholars Science Foundation of Lanzhou Jiaotong University(No.2022023)the Fundamental Research Funds for the Central Universities,and the Youth Science and Technology Foundation of Gansu Province(Nos.22JR5RA541 and 22JR5RA374).
文摘Room-temperature sodium-sulfur(RT Na-S)batteries have been regarded as promising energy storage technologies in grid-scale stationary energy storage systems due to their low cost,natural abundance,and high-energy density.However,the practical application of RT Na-S batteries is hindered by low reversible capacity and unsatisfying long-cycling performance arising from the severe shuttle effect and sluggish S redox kinetics.This review provides an overview of recent efforts for the optimization strategies of the electronic structure of catalysts via catalyst engineering to enhance the adsorption and catalytic activity toward soluble long-chain sodium polysulfides(NaPSs).Finally,the current challenges and prospects for further optimization strategies of catalysts,understanding catalysis and structural evolution mechanism,and achieving practical applications are highlighted to meet the commercial requirements of RT Na-S batteries.
文摘By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variational Zn-salen ligands RZn and NADH(reduced nicotinamide adenine dinucleotide)mimic modified tridentate ligands with square-planar Pd ions.UV-Vis and luminescence spectra experiments reveal that different anions could selec-tively interact with different sites of Zn-salen modified metal-organic cages to achieve the structural regulation of cage compound,by using the differentiated host-vip electrostatic interactions of counter ions with metal-organic hosts.Compared to other anions,the presence of chloride ions caused the most significant fluorescence emission enhancement of Pd‑R(Zn),meanwhile,the UV-Vis absorption band attributed to the salen aromatic backbone showed an absorption decrease,and the metal-to-ligand induced peak displayed a blue shift effect.Circular dichro-ism and ^(1)H NMR spectra further demonstrate that the introduction of chloride anions is beneficial to keeping a more rigid scaffold.
基金sponsored by the National Natural Science Foundation of China(Nos.5210125 and 52375422)the Science Research Project of Hebei Education Department(No.BJK2023058)the Natural Science Foundation of Hebei Province(Nos.E2020208069,B2020208083 and E202320801).
文摘The stability and electrocatalytic efficiency of transition metal oxides for water splitting is determined by geometric and electronic structure,especially under high current densities.Herein,a newly designed lamella-heterostructured nanoporous CoFe/CoFe_(2)O_(4) and CeO_(2−x),in situ grown on nickel foam(NF),holds great promise as a high-efficient bifunctional electrocatalyst(named R-CoFe/Ce/NF)for water splitting.Experimental characterization verifies surface reconstruction from CoFe alloy/oxide to highly active CoFeOOH during in situ electrochemical polarization.By virtues of three-dimensional nanoporous architecture and abundant electroactive CoFeOOH/CeO_(2−x) heterostructure interfaces,the R-CoFe/Ce/NF electrode achieves low overpotentials for oxygen evolution(η_(10)=227 mV;η_(500)=450 mV)and hydrogen evolution(η_(10)=35 mV;η_(408)=560 mV)reactions with high normalized electrochemical active surface areas,respectively.Additionally,the alkaline full water splitting electrolyzer of R-CoFe/Ce/NF||R-CoFe/Ce/NF achieves a current density of 50 mA·cm^(−2) only at 1.75 V;the decline of activity is satisfactory after 100-h durability test at 300 mA·cm^(−2).Density functional theory also demonstrates that the electron can transfer from CeO_(2−x) by virtue of O atom to CoFeOOH at CoFeOOH/CeO_(2−x) heterointerfaces and enhancing the adsorption of reactant,thus optimizing electronic structure and Gibbs free energies for the improvement of the activity for water splitting.
基金supported by the National Natural Science Foundation of China(Nos.22178388 and 22108306)Taishan Scholars Program of Shandong Province(No.tsqn201909065)Chongqing Science and Technology Bureau(No.cstc2019jscx-gksb X0032).
文摘Structural regulation of Pd-based electrocatalytic hydrodechlorination(EHDC)catalyst for constructing high-efficient cathode materials with low noble metal content and high atom utilization is crucial but still challenging.Herein,a support electron inductive effect of Pd-Mn/Ni foam catalyst was proposed via in-situ Mn doping to optimize the electronic structure of the Ni foam(NF),which can inductive regulation of Pd for improving the EHDC performance.The mass activity and current efficiency of Pd-Mn/NF catalyst are 2.91 and 1.34 times superior to that of Pd/NF with 2,4-dichlorophenol as model compound,respectively.The Mn-doped interlayer optimized the electronic structure of Pd by bringing the d-state closer to the Fermi level than Pd on the NF surface,which optimizied the binding of EHDC intermediates.Additionally,the Mn-doped interlayer acted as a promoter for generating H∗and accelerating the EHDC reaction.This work presents a simple and effective regulation strategy for constructing high-efficient cathode catalyst for the EHDC of chlorinated organic compounds.
文摘Smart batteries play a key role in upgrading energy storage systems.However,they require a well-balanced integration of material structure,functional properties,and electrochemical performance,and their development is limited by conventional material systems in terms of energy density,response time,and functional integration.Carbon materials have emerged as a key solution for overcoming these problems due to their structural adjustability and multifunctional compatibility.Strategies for improving their electrochemical performance by changing the pore structure and interlayer spacing,as well as chemical functionalization,and composite design are analyzed,and their impact on improving the specific capacity and cycling stability of batteries is demonstrated.The unique advantages of carbon materials in realizing smart functions such as power supply,real-time monitoring and energy management in smart batteries are also discussed.Based on current progress in related fields,the prospects for the use of carbon materials in smart batteries are evaluated.
基金supported by the National Natural Science Foundation of China(Grant Nos.52272208,22309057)the Natural Science Foundation of Hubei Province(Grant No.2023AFB355)the Fundamental Research Funds for the Central Universities of China(Grant No.2662022LXQD001).
文摘Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type secondary batter-ies,DIBs perform a unique working mechanism,which employ both cation and anion taking part in capacity contribution at an anode and a cathode,respectively,during electrochemical reactions.Graphite has been identified as a suitable cathode material for anion intercalation at high voltages(>4.8 V)with fast reaction kinetics.However,the development of DIBs is being hindered by dynamic mismatch between a cathode and an anode due to sluggish Li+diffusion at a high rate.Herein,we prepared phyllostachys edulis derived carbon(PEC)through microstructure regulation strategy and investigated the carbonized temperature effect,which effectively tailored the rich short-range ordered graphite microdomains and disor-dered amorphous regions,as well as a unique nano-pore hierarchical structure.The pore size distribution of nano-pores was concentrated in 0.5-5 nm,providing suitable channels for rapid Li+transportation.It was found that PEC-500(carbon-ized at 500℃)achieved a high capacity of 436 mAh·g^(-1)at 300 mA·g^(-1)and excellent rate performance(maintaining a high capacity of 231 mAh·g^(-1)at 3 A·g^(-1)).The assembled dual-carbon PEC-500||graphite full battery delivered 114 mAh·g^(-1)at 10 C with 96%capacity retention after 3000 cycles and outstanding rate capability,providing 74 mAh·g^(-1)at 50 C.
文摘Biomass-derived hard carbons,usually prepared by pyrolysis,are widely considered the most promising anode materials for sodium-ion bat-teries(SIBs)due to their high capacity,low poten-tial,sustainability,cost-effectiveness,and environ-mental friendliness.The pyrolysis method affects the microstructure of the material,and ultimately its so-dium storage performance.Our previous work has shown that pyrolysis in a sealed graphite vessel im-proved the sodium storage performance of the car-bon,however the changes in its microstructure and the way this influences the sodium storage are still unclear.A series of hard carbon materials derived from corncobs(CCG-T,where T is the pyrolysis temperature)were pyrolyzed in a sealed graphite vessel at different temperatures.As the pyrolysis temperature increased from 1000 to 1400℃ small carbon domains gradually transformed into long and curved domains.At the same time,a greater number of large open pores with uniform apertures,as well as more closed pores,were formed.With the further increase of pyrolysis temperature to 1600℃,the long and curved domains became longer and straighter,and some closed pores gradually became open.CCG-1400,with abundant closed pores,had a superior SIB performance,with an initial reversible ca-pacity of 320.73 mAh g^(-1) at a current density of 30 mA g^(-1),an initial Coulomb efficiency(ICE)of 84.34%,and a capacity re-tention of 96.70%after 100 cycles.This study provides a method for the precise regulation of the microcrystalline and pore structures of hard carbon materials.
基金supported by the National Natural Science Foundation of China(No.51874036)the Natural Science Foundation of Ningxia(No.2024AAC02034)。
文摘Two-dimensional(2D) nanomaterials have always been regarded as having great development potential in the field of oil-based lubrication due to their designable structures,functional groups,and abundant active sites.However,understanding the structure-performance relationship between the chemical structure of 2D nanomaterials and their lubrication performance from a comprehensive perspective is crucial for guiding their future development.This review provides a timely and comprehensive overview of the applications of 2D nanomaterials in oil-based lubrication.First,the bottlenecks and mechanisms of action of 2D nanomaterials are outlined,including adsorption protective films,charge adsorption effects,tribochemical reaction films,interlayer slip,and synergistic effects.On this basis,the review summarizes recent structural regulation strategies for 2D nanomaterials,including doping engineering,surface modification,structural optimization,and interfacial mixing engineering.Then,the focus was on analyzing the structure-performance relationship between the chemical structure of 2D nanomaterials and their lubrication performance.The effects of thickness,number of layers,sheet diameter,interlayer spacing,Moiré patterns,wettability,functional groups,concentration,as well as interfacial compatibility and dispersion behavior of 2D nanomaterials were systematically investigated in oil-based lubrication,with the intrinsic correlations resolved through computational simulations.Finally,the review offers a preliminary summary of the significant challenges and future directions for 2D nanomaterials in oil-based lubrication.This review aims to provide valuable insights and development strategies for the rational design of high-performance oil-based lubrication materials.
基金supported by the National Natural Science Foundation of China(52271210,22179032,52171176)。
文摘Exploring efficient transition-metal-based electrocatalysts is critical for the wide application of electrochemical hydrogen generation technology.Although the phase displays prominent influence on their performance,it remains a major challenge to achieve phase regulation in the same synthesis method and elucidate the intrinsic relationship between the phase and activity.Herein,we developed a sulfur induced electrodeposition strategy to achieve the precise phase regulation of nickel-based materials from Ni(OH)_(2)to Ni and Ni_(3)S_(2).S atoms can be introduced into Ni and Ni(OH)_(2)due to sulfur inducement,and the S proportion is finely controlled via changing the deposition parameters.Importantly,the obtained S-Ni catalyst displays enhanced hydrogen evolution activity with an ultralow overpotential of 27 mV at 10 mA cm^(-2),which is superior to the S-Ni(OH)_(2),Ni_(3)S_(2),and even Pt/C.Density functional theory(DFT)calculations disclose the S-Ni catalyst exhibits optimal charge state and local coordination,remarkably optimizing the water adsorption and Ni-H^(*)binding energy.This work provides new insights into phase regulation in electrodeposition and an understanding of the intrinsic relationship between phase and activity.
基金supported by the National Key Research and Development Program of China(2021YFF0500600)National Natural Science Foundation of China(Nos.U2001220,52203298 and 523B2022)+2 种基金National Science Fund for Distinguished Young Scholars(No.52325206)Shenzhen Technical Plan Project(Nos.RCJC20200714114436091,JCYJ20220530143012027,JCYJ20220818101003008 and JCYJ20220818101003007)Tsinghua Shenzhen International Graduate School-Shenzhen Pengrui Young Faculty Program of Shenzhen Pengrui Foundation(No.SZPR2023006).
文摘Nickel(Ni)-rich layered oxides have drawn great attention as cathode for lithium batteries due to their high capacity,high working voltage and competitive cost.Unfortunately,the operation of Ni-rich cathodes suffers from the notorious structural degradation and interfacial side reactions with electrolytes and thus incurs premature failure,especially at high charge cut-off voltages(≥4.4 V).For this,various structural and interphase regulation strategies(such as coating modification,element doping,and electrolyte engineering)are developed to enhance the cycling survivability of Ni-rich cathodes.Among them,electrolyte engineering by changing solvation structure and introducing additives has been considered an efficient method for constructing robust cathode-electrolyte interphases(CEI),inhibiting the formation of harmful species(such as HF and H_(2)O)or restraining the dissolution of transition metal ions.However,there is still an absence of systematic guidelines for selecting and designing competitive electrolyte systems for Ni-rich layered cathodes.In this review,we comprehensively summarize the recent research progress on electrolyte engineering for Ni-rich layered cathodes according to their working mechanisms.Moreover,we propose future perspectives of improving the electrolyte performance,which will provide new insights for designing novel electrolytes toward high-performance Ni-rich layered cathodes.
基金supported by the National Natural Science Foundation of China(Nos.22322104,22171074)the Natural Science Foundation of Heilongjiang Province(No.YQ2021B009)+3 种基金the Reform and Development Fund Project of Local University supported by the Central Government(Outstanding Youth Program)Heilongjiang Province Young Scientific and Technological Talent Lifting Project(No.2023QNTJ019)the Basic Research Support Project for Outstanding Young Teachers in Heilongjiang Provincial University(No.YQJH2023129)the Outstanding Youth Science Foundation of Heilongjiang University(No.JCL202301)。
文摘Urea-assisted water electrolysis offers a promising route to reduce energy consumption for hydrogen production and meanwhile treat urea-rich wastewater.Herein,we devised a shear force-involved polyoxometalate-organic supramolecular self-assembly strategy to fabricate 3D hierarchical porous nanoribbon assembly Mn-VN cardoons.A bimetallic polyoxovanadate(POV)with the inherent structural feature of Mn surrounded by[VO_(6)]octahedrons was introduced to trigger precise Mn incorporation in VN lattice,thereby achieving simultaneous morphology engineering and electronic structure modulation.The lattice contraction of VN caused by Mn incorporation drives electron redistribution.The unique hierarchical architecture with modulated electronic structure that provides more exposed active sites,facilitates mass and charge transfer,and optimizes the associated adsorption behavior.Mn-VN exhibits excellent activity with low overpotentials of 86 m V and 1.346 V at 10 m A/cm^(2)for hydrogen evolution reaction(HER)and urea oxidation reaction(UOR),respectively.Accordingly,in the two-electrode urea-assisted water electrolyzer utilizing Mn-VN as a bifunctional catalyst,hydrogen production can occur at low voltage(1.456 V@10 m A/cm^(2)),which has the advantages of energy saving and competitive durability over traditional water electrolysis.This work provides a simple and mild route to construct nanostructures and modulate electronic structure for designing high-efficiency electrocatalysts.
基金supported by the National Natural Science Foundation of China(22178276,221760110,22178275)the Postdoctoral Fellowship Program of CPSF(GZC20240888)the Postdoctoral Project of Hubei Province(2024HBBHCXB053).
文摘Pd catalyst with high activity and selectivity for O_(2)reduction to H_(2)O_(2)is highly desirable.However,metallic Pd catalyst suffers from limited activity and selectivity in H_(2)O_(2)photosynthesis due to intrinsically strong O_(2)adsorption at Pd atom sites.Herein,a strategy is proposed to modulate the electronic structure,aiming to weaken O_(2)adsorption and further enhance O_(2)-reduction selectivity through the creation of highly dispersed and electron-enriched Pd^(δ-)atom sites.To achieve this,a novel photochemical plating approach is employed to selectively grow vertical Bi nanosheets on the(010)facet of BiVO_(4).This process confines highly dispersed Pd atoms within the Bi nanosheets,forming a PdBi cocatalyst that significantly boosts H_(2)O_(2)photosynthesis.Notably,the optimized PdBi/BiVO_(4)photocatalyst achieves a high H_(2)O_(2)production concentration of 2246.43μmol L−1,with an apparent quantum efficiency(AQE)of 11.16%,realizing a 1.74-fold enhancement in activity compared to Pd/BiVO_(4)(1289.28μmol L^(−1)).Theoretical calculation and experimental results confirm that the vertical-growth Bi nanosheets induce the formation of well-dispersed and electron-enriched Pd^(δ−)atom sites.This accordingly increases the antibonding-orbital occupancy of Pd-O_(ads),thereby weakening O_(2)adsorption and ultimately facilitating selective O_(2)reduction for photocatalytic H_(2)O_(2)production.This rational design of Pd-based catalysts provides a promising strategy for modulating the electronic structure of active atoms to advance artificial photosynthesis.
基金supported by the National Natural Science Foundation of China(Grant No.22108306)the Taishan Scholars Program of Shandong Province(Grant No.tsqn201909065)the Shandong Provincial Natural Science Foundation(Grant Nos.ZR2021YQ15,ZR2020QB174)。
文摘The development and utilization of renewable clean energy can effectively solve the two major problems of energy and environment. As an efficient power generation device that converts hydrogen energy into electric energy, fuel cell has attracted more and more attention. For fuel cells, the oxygen reduction reaction(ORR) at the cathode is the core reaction, and the design and development of high-performance ORR catalysts remain quite challenging. Since the microenvironment of the active center of single atom catalysts(SACs) has an important influence on its catalytic performance, it has been a research focus to improve the ORR activity and stability of electrocatalysts by adjusting the structure of the active center through reasonable structural regulation methods. In this review, we reviewed the preparation and structure–activity relationship of SACs for ORR. Then, the structural precision regulation methods for improving the activity and stability of ORR electrocatalysts are discussed. And the advanced in-situ characterization techniques for revealing the changes of active sites in the electrocatalytic ORR process are summarized. Finally, the challenges and future design directions of SACs for ORR are discussed. This work will provide important reference value for the design and synthesis of SACs with high activity and stability for ORR.
基金the National Natural Science Foundation of China(Nos.22105059 and 2210051199)the Talent Introduction Program of Hebei Agricultural University(No.YJ201810)+3 种基金Qingdao Source Innovation Project(No.19-6-2-19-cg)the Natural Science Foundation of Shandong Province(No.ZR2021QE192)the Natural Science Foundation of Hebei Province(No.B2019204009)the China Postdoctoral Science Foundation(No.2018M630747)。
文摘Poor conductivity and sluggish Na^(+) diffusion kinetic are two major drawbacks for practical application of sodium super-ionic conductor(NASICON) in sodium-ion batteries. In this work, we report a simple approach to synthesize quasi-inverse opal structural NASICON/N-doped carbon for the first time by a delicate one-pot solution-freeze drying-calcination process, aiming at fostering the overall electrochemical performance. Especially, the quasi-inverse opal structural Na_(3)V_(2)(PO_(4))_(3)/N-C(Q-NVP/N-C) displayed continuous pores, which provides interconnected channels for electrolyte permeation and abundant contacting interfaces between electrolyte and materials, resulting in faster kinetics of redox reaction and higher proportion of capacitive behavior.As a cathode material for sodium-ion batteries, the Q-NVP/N-C exhibits high specific capacity of 115 mAh·g^(-1) at 1C, still 61 mAh·g^(-1) at ultra-high current density of 100C,and a specific capacity of 89.7mAh·g^(-1) after 2000 cycles at 20C.This work displays the general validity of preparation method for not only Q-NVP/N-C,but also Na_(3)V_(2)(PO_(4))_(3),which provides a prospect for delicate synthesis of NASICON materials with excellent electrochemical performance.
文摘Benefiting from the ultrahigh specific surface areas,highly accessible surface atoms,and highly tunable microscopic structures,the two-dimensional metallenes as nanocatalysts have displayed promising performance for various electrocatalytic reactions.Herein,we reviewed recent advances on metallenes in structural regulations including defect,phase,strain,interface,doping,and alloying engineering strategies and their applications in energy electrocatalytic reactions involving oxygen reduction reaction,carbon dioxide reduction reaction,hydrogen evolution reaction,and small molecules oxidation reaction.Finally,we proposed the future challenges and directions in this emerging area.
文摘Based on the overall consideration of individual behaviors of Ricardian and non-Ricardian households, this paper develops a New Keynesian dynamic stochastic general equilibrium(DSGE) model to form a relatively systematic research framework for analyzing the economic effects of structural fiscal instruments. Our study findsthat great differences exist in the macroeconomic effects of different fiscal instruments, suggesting that the government should prudently select these fiscal instruments in fiscal macro-control. The simulating results of fiscal shocks show that the effect of tax cut is superior to the effect of increased spending. In the context of slowing economic growth and less potent stimulation policy, the government should transform its previous regulatory approach of fiscal policy and shift from hefty spending stimulus policy to structural tax cuts. This paper believes that China should step up the implementation of public-private partnership, increase its spending on social security, healthcare, pension and public services and facilitate the transition toward a service-based government; and that tax policy should focus on structural tax cuts on consumption to promote the transition of demand structure toward consumption-driven.
