Constrained by severe bulk charge recombination,the actual photocurrent density of tantalum nitride(Ta_(3)N_(5))photoanode is much lower than the theoretical maximum value.Herein,we report the doping of phosphorus,a n...Constrained by severe bulk charge recombination,the actual photocurrent density of tantalum nitride(Ta_(3)N_(5))photoanode is much lower than the theoretical maximum value.Herein,we report the doping of phosphorus,a non-metallic element distinct from oxygen,into Ta_(3)N_(5),resulting in a photocurrent density 9 times higher than that of pristine Ta_(3)N_(5).Systematic characterization reveals that the phosphorus doping simultaneously enhances the bulk charge separation efficiency and surface charge injection efficiency of Ta_(3)N_(5),and induces favorable band energy restructuring.Specifically,a type-II homojunction formed between phosphorus-doped near-surface region and bulk Ta_(3)N_(5) effectively promotes the separation and transfer of photogenerated holes and electrons.Further modification with a Ni Fe-based cocatalyst enables the optimized photoanode to deliver a photocurrent density of 10 mA/cm^(2) at 1.23 V versus the reversible hydrogen electrode(RHE)and an applied bias photo-to-current efficiency of 1.78%at 0.95 V versus RHE.Our work provides a foundation for the development of a broader range of non-metal doped semiconductors.展开更多
Doping with various impurities is an effective approach to improve the photoelectrochemical properties of TiO2. Here, we explore the effect of oxygen vacancy on geometric and elec- tronic properties of compensated （i...Doping with various impurities is an effective approach to improve the photoelectrochemical properties of TiO2. Here, we explore the effect of oxygen vacancy on geometric and elec- tronic properties of compensated （i.e. V-N and Cr-C） and non-compensated （i.e. V-C and Cr-N） codoped anatase TiO2 by performing extensive density functional theory calculations. Theoretical results show that oxygen vacancy prefers to the neighboring site of metal dopant （i.e. V or Cr atom）. After introduction of oxygen vacancy, the unoccupied impurity bands located within band gap of these codoped TiO2 will be filled with electrons, and the posi- tion of conduction band offset does not change obviously, which result in the reduction of photoinduced carrier recombination and the good performance for hydrogen production via water splitting. Moreover, we find that oxygen vacancy is easily introduced in V-N codoped TiO2 under O-poor condition. These theoretical insights are helpful for designing codoped TiO2 with high photoelectrochemical performance.展开更多
Metal halide perovskite nanostructures have emerged as low-dimensional semiconductors of great significance in many fields such as photovoltaics,photonics,and optoelectronics.Extensive efforts on the controlled synthe...Metal halide perovskite nanostructures have emerged as low-dimensional semiconductors of great significance in many fields such as photovoltaics,photonics,and optoelectronics.Extensive efforts on the controlled synthesis of perovskite nanostructures have been made towards potential device applications.The engineering of their band structures holds great promise in the rational tuning of the electronic and optical properties of perovskite nanostructures,which is one of the keys to achieving efficient and multifunctional optoelectronic devices.In this article,we summarize recent advances in band structure engineering of perovskite nanostructures.A survey of bandgap engineering of nanostructured perovskites is firstly presented from the aspects of dimensionality tailoring,compositional substitution,phase segregation and transition,as well as strain and pressure stimuli.The strategies of electronic doping are then reviewed,including defect-induced self-doping,inorganic or organic molecules-based chemical doping,and modification by metal ions or nanostructures.Based on the bandgap engineering and electronic doping,discussions on engineering energy band alignments in perovskite nanostructures are provided for building high-performance perovskite p-n junctions and heterostructures.At last,we provide our perspectives in engineering band structures of perovskite nanostructures towards future low-energy optoelectronics technologies.展开更多
Although lithium-sulfur batteries are one of the favorable candidates for next-generation energy storage devices,a few key challenges that have not been addressed have limited its commercialization.These challenges in...Although lithium-sulfur batteries are one of the favorable candidates for next-generation energy storage devices,a few key challenges that have not been addressed have limited its commercialization.These challenges include lithium dendrite growth in the anode side,volume change of the active material,poor electrical conductivity,dissolution and migration of poly sulfides,and slow rate of solid-state reactions in the cathode side.Since the electrochemical performance of lithium-sulfur batteries is greatly affected by the design of the cathode host material,it has also been widely discussed in addressing the abovementioned issues.In this paper,three design ideas of cathode host materials in terms of microstructure,crystal structure and electronic structure are introduced and summarized.Crucially,the current progress of these three structural design strategies and their effects on the electrochemical performance of lithium-sulfur batteries are discussed in detail.Finally,future directions in the structural design of cathode materials for lithium-sulfur batteries are discussed and further perspectives are provided.展开更多
The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various field...The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance.展开更多
Artificially constructed van der Waals heterostructures(vdWHs)provide an ideal platform for realizing emerging quantum phenomena in condensed matter physics.Two methods for building vdWHs have been developed:stacking ...Artificially constructed van der Waals heterostructures(vdWHs)provide an ideal platform for realizing emerging quantum phenomena in condensed matter physics.Two methods for building vdWHs have been developed:stacking two-dimensional(2D)materials into a bilayer structure with different lattice constants,or with different orientations.The interlayer coupling stemming from commensurate or incommensurate superlattice pattern plays an important role in vdWHs for modulating the band structures and generating new electronic states.In this article,we review a series of novel quantum states discovered in two model vdWH systems—graphene/hexagonal boron nitride(hBN)hetero-bilayer and twisted bilayer graphene(tBLG),and discuss how the electronic structures are modified by such stacking and twisting.We also provide perspectives for future studies on hetero-bilayer materials,from which an expansion of 2D material phase library is expected.展开更多
With the continuous development of urbanization construction, rail transit has received more and more attention. For the current subway station, the main structure of open-cut subway station plays an important role in...With the continuous development of urbanization construction, rail transit has received more and more attention. For the current subway station, the main structure of open-cut subway station plays an important role in it. Therefore, the leakage problem with high frequency should be analyzed in time and dealt with reasonably. In this paper, the construction technology of leakage treatment for the main structure of open-cut subway station is analyzed for reference.展开更多
Architectural structure engineering occupies a major position in architectural engineering and has a direct impact on the design quality of the whole building. As far as architectural structure design is concerned, sa...Architectural structure engineering occupies a major position in architectural engineering and has a direct impact on the design quality of the whole building. As far as architectural structure design is concerned, safety and durability have received more and more attention, which are also the two major focuses of current architectural structure engineering design. However, there are still some problems in carrying out these two tasks, which greatly affect the final construction quality. This paper studies the durability and safety of building structure engineering, hoping to effectively improve the overall design quality of building structure and meet the living needs.展开更多
The construction project in the actual construction process, in order to comprehensively ensure the construction quality, we should strengthen the importance of the main design of the building, and through the applica...The construction project in the actual construction process, in order to comprehensively ensure the construction quality, we should strengthen the importance of the main design of the building, and through the application of standardized construction technology, reasonable control of the construction progress and quality, to ensure the smooth progress of the follow-up work. Based on this, this paper mainly around the importance of the construction of the main structure of the building to launch an analysis, elaborated the technical application countermeasures.展开更多
It is not difficult to find out that cracks in concrete structural engineering are ubiquitous. Because the damage of the structure often begins with cracks, it brings harm and risk to social production and life. Espec...It is not difficult to find out that cracks in concrete structural engineering are ubiquitous. Because the damage of the structure often begins with cracks, it brings harm and risk to social production and life. Especially with the rapid development of my country's capital construction in recent decades, it is very necessary to understand and solve the ancient and novel problem of cracks in concrete structures. With the exploration and research of long-term engineering practice, with the continuous development of technology and productivity, people have realized that the generation of harmful cracks can be controlled through effective technical means. That is to say, through the organic combination of design and construction, the influence of cracks can be prevented from being harmful.展开更多
Vacancy engineering is highly effective in optimizing the electrochemical performance of transition-metal selenide anodes for sodium-ion batteries.However,traditional construction strategies face the problems of low v...Vacancy engineering is highly effective in optimizing the electrochemical performance of transition-metal selenide anodes for sodium-ion batteries.However,traditional construction strategies face the problems of low vacancy stability,additional internal structure destruction for the host material,limited vacancy content and a complicated preparation process with high energy consumption.Here we for the first time demonstrated that an aligned carbon matrix with the abundant low-tortuosity channels is capable of effectively inducing the formation of abundant selenium vacancies in the transition-metal selenide anode,meanwhile existing stably throughout its long-term cycle process.Benefiting from the advantage that abundant selenium vacancies with high stability can continuously restrain the polyselenides dissolution in the electrolyte,the prepared anode exhibits significantly improved cycling stability.Meanwhile,the fast mass and charge transport allowed by both the abundant aligned straight channels and selenium vacancies also promise it an exceptionally excellent rate capability with an ultrahigh capacity retention of 95.1%when increasing the current density from 8 to 16 A g^(-1).Impressively,it also accomplishes a remarkable fast-charging performance with about 90 s for continuous 500 cycles at up to 16 A g^(-1),accompanied with the high-rate capacity of 417.7 mAh g^(-1)and capacity retention above 92%.This work may bring a paradigm shift in the traditional selenium-deficient modulation strategy to carbon matrix structure engineering for functionalizing transition-metal selenides.展开更多
Achieving high performance electronic structure engineering in multi-component photocatalysts to effectively coordinate photoinduced carrier migration and surface reaction dynamics is still a key obstacle for solar-dr...Achieving high performance electronic structure engineering in multi-component photocatalysts to effectively coordinate photoinduced carrier migration and surface reaction dynamics is still a key obstacle for solar-driven hydrogen production.Herein,well-defined ZnIn_(2)S_(4) nanosheets modified with metallic 1T-phase WS_(2) and Ni_(2)P dual cocatalysts with superior photoactivity and stability were fabricated by twostep ultrasonic self-assembly processes.A series of photoelectrochemical characterization studies revealed that the metallic phase 1T-WS_(2) with excellent conductivity can effectively lower the charge transport resistance and enhance electron transfer efficiency,while Ni_(2)P with abundant active sites can efficiently promote the surface H_(2)-production reaction dynamics in this dual cocatalyst system.Moreover,the synergistic effects of the 1T-WS_(2) and Ni_(2)P dual cocatalysts can boost the oxidation efficiency of the sacrificial regents(lactic acid)by elevating the valence band levels of ZnIn_(2)S_(4),which in turn promotes the separation of photocarriers.As a result,the optimized tandem Ni_(2)P/1T-WS_(2)/ZnIn_(2)S_(4) ternary heterojunction with a cascade electron transfer pathway achieved a peak hydrogen generation rate of 17.01 mmol g^(-1) h^(-1),roughly 3.34,1.56 and 1.36 times greater than those of bare ZnIn_(2)S_(4),binary 1T-WS_(2)/ZnIn_(2)S_(4) and Ni_(2)P/ZnIn_(2)S_(4),respectively.This work not only provides mechanistic insights into how dual cocatalysts influence electronic structure engineering and charge transfer dynamics but also establishes a versatile framework for the design of multi-component heterojunctions for more efficient and sustainable solarto-fuel conversion.展开更多
Kinked rebar is a special type of steel material,which is installed in beam column nodes and frame beams.It effectively enhances the blast resilience,seismic collapse resistance,and progressive collapse resistance of ...Kinked rebar is a special type of steel material,which is installed in beam column nodes and frame beams.It effectively enhances the blast resilience,seismic collapse resistance,and progressive collapse resistance of reinforced concrete(RC)structures without imposing substantial cost burdens,thereby emerging as a focal point of recent research endeavors.On the basis of explaining the working principle of kinked rebars,this paper reviews the research status of kinked rebars at home and abroad from three core domains:the tensile mechanical properties of kinked rebars,beam column nodes with kinked rebars,and concrete frame structures with kinked rebars.The analysis underscores that the straightening process of kinked rebars does not compromise their ultimate strength but significantly bolsters structural ductility and enhances energy dissipation capabilities.In beam-column joints,the incorporation of kinked rebars facilitates the seamless transfer of plastic hinges,adhering to the design principle of“strong columns and weak beams.”In addition,kinked rebars can greatly improve the resistance of the beam;The seismic resistance,internal explosion resistance,and progressive collapse resistance of reinforced concrete frame structures with kinked rebar have significantly improved.Beyond its primary application,the principle of kinked rebar was extended to other applications of kinked materials such as corrugated steel plates and origami structures,and the stress characteristics of related components and structures were studied.Intriguingly,this paper also proposes the application of kinked rebars in bridge engineering,aiming to address the challenges of localized damage concentration and excessive residual displacement in RC bridge piers.The introduction of kinked rebars in piers is envisioned to mitigate these issues,with the paper outlining its advantages and feasibility,thereby offering valuable insights for future research on kinked reinforcement and seismic design strategies for bridges.展开更多
The Reliability-Based Design Optimization(RBDO)of complex engineering structures considering uncertainties has problems of being high-dimensional,highly nonlinear,and timeconsuming,which requires a significant amount ...The Reliability-Based Design Optimization(RBDO)of complex engineering structures considering uncertainties has problems of being high-dimensional,highly nonlinear,and timeconsuming,which requires a significant amount of sampling simulation computation.In this paper,a basis-adaptive Polynomial Chaos(PC)-Kriging surrogate model is proposed,in order to relieve the computational burden and enhance the predictive accuracy of a metamodel.The active learning basis-adaptive PC-Kriging model is combined with a quantile-based RBDO framework.Finally,five engineering cases have been implemented,including a benchmark RBDO problem,three high-dimensional explicit problems,and a high-dimensional implicit problem.Compared with Support Vector Regression(SVR),Kriging,and polynomial chaos expansion models,results show that the proposed basis-adaptive PC-Kriging model is more accurate and efficient for RBDO problems of complex engineering structures.展开更多
With the rapid development of science and technology,the application of intelligent technology in the field of civil engineering is more extensive,especially in the safety evaluation and management of engineering stru...With the rapid development of science and technology,the application of intelligent technology in the field of civil engineering is more extensive,especially in the safety evaluation and management of engineering structures.This paper discusses the role of intelligent technologies(such as artificial intelligence,Internet of Things,BIM,big data analysis,etc.)in the monitoring,evaluation,and maintenance of engineering structure safety.By studying the principle,application scenarios,and advantages of intelligent technology in structural safety evaluation,this paper summarizes how intelligent technology can improve engineering management efficiency and reduce safety risks,and puts forward the trend and challenge of future development.展开更多
The conversion of carbon dioxide(CO_(2))into hydrocarbons through electrochemical CO_(2)reduction reaction(eCO_(2)RR)shows a promising method to reduce CO_(2)levels and decrease reliance on fossil fuels in the years t...The conversion of carbon dioxide(CO_(2))into hydrocarbons through electrochemical CO_(2)reduction reaction(eCO_(2)RR)shows a promising method to reduce CO_(2)levels and decrease reliance on fossil fuels in the years to come.Copper-based electrocatalysts exhibit a pronounced inclination for C-C coupling,drawing considerable interest as a favored metal catalyst for generating C_(2+)products through CO_(2)RR.However,CO_(2)RR still has some obstacles including product selectivity,higher overpotential,low Faradic efficiency(FE),stability,and current density(CD).Therefore,advancement in this field enables us to comprehend the complex multi-proton electron transfer during C-C coupling and engineering strategies to improve FE and CD.Herein,this review presents some key features of Cu-based catalysts as an electrocatalyst for C_(2) product formation while addressing the industrial challenges that hinder commercialization of CO_(2)RR.In addition,recent strategies on Cu-based catalysts,synthesis strategies,advanced characterizations,and mechanistic investigations via theoretical simulations have been presented.Furthermore,recent approaches towards the composition,oxidation states,and active facets have been presented.Thus,the most favorable mechanism and possible pathways to synthesize C_(2+)products have been explained using theoretical calculations.展开更多
Silicon(Si)-based anodes have emerged as promising candidates for the next-generation lithium-ion batteries(LIBs)due to their high theoretical capacity(4200 mAh g^(-1)).However,their further application is hindered by...Silicon(Si)-based anodes have emerged as promising candidates for the next-generation lithium-ion batteries(LIBs)due to their high theoretical capacity(4200 mAh g^(-1)).However,their further application is hindered by critical challenges,including severe volume expansion(~300%),formation of unstable solid electrolyte interphase(SEI),and inherently low conductivity.While extensive research has sought to alleviate the substantial internal stress caused by volume expansion through the rational design of Si-based anode structures,the underlying mechanisms that govern these improvements remain insufficiently understood,leaving significant gaps in mechanical and interface electrical failure.To build a comprehensive understanding relationship between structural design and performance enhancement of Si-based anodes,this review first analyzes the characteristics of various Sibased anode structures and their associated internal stresses.Subsequently,it summarizes effective strategies to optimize the performance of Si-based anodes,including doping design,novel electrolyte design,and fu nctional binder design.Additionally,we assess emerging technologies with high commercial potential for structural design and interfacial modification,such as porous carbon carriers,chemical vapor deposition(CVD),spray granulation,and pre-lithiation.Finally,this work provides perspectives on the structural design of Si-based anodes.Overall,this review systematically summarizes modification strategies for Si-based anodes through structural regulation and interface engineering,thereby providing a foundation for advanced structural and interfacial design.展开更多
The widespread application of photodetectors has triggered an urgent need for high-sensitivity and polarization-dependent photodetection.In this field,the two-dimensional(2D)tungsten disulfide(WS_(2))exhibits intrigui...The widespread application of photodetectors has triggered an urgent need for high-sensitivity and polarization-dependent photodetection.In this field,the two-dimensional(2D)tungsten disulfide(WS_(2))exhibits intriguing optical and electronic properties,making it an attractive photosensitive material for optoelectronic applications.However,the lack of an effective built-in electric field and photoconductive gain mechanism in 2D WS_(2)impedes its application in high-performance photodetectors.Herein,we propose a hybrid heterostructure photodetector that contains 1D Te and 2D WS_(2).In this device,1D Te induces in-plane strain in 2D WS_(2),which regulates the electronic structures of local WS_(2)and gives rise to type-Ⅱ band alignment in the horizontal direction.Moreover,the vertical heterojunction built of 2D WS_(2)and 1D Te introduces a high photoconductive gain.Benefiting from these two effects,the transfer of photogenerated carriers is optimized,and the proposed photodetector exhibits high sensitivity(photoresponsivity of ~27.7 A W^(-1),detectivity of 9.5×10^(12)Jones,and short rise/decay time of 19.3/17.6 ms).In addition,anisotropic photodetection characteristics with a dichroic ratio up to 2.1 are achieved.This hybrid 1D/2D heterostructure overcomes the inherent limitations of each material and realizes novel properties,opening up a new avenue towards constructing multifunctional optoelectronic devices.展开更多
With the rapid growth in renewable energy,researchers worldwide are trying to expand energy storage technologies.The development of beyond-lithium battery technologies has accelerated in recent years,amid concerns reg...With the rapid growth in renewable energy,researchers worldwide are trying to expand energy storage technologies.The development of beyond-lithium battery technologies has accelerated in recent years,amid concerns regarding the sustainability of battery materials.However,the absence of suitable high-performance materials has hampered the development of the next-generation battery systems.MXenes,a family of 2D transition metal carbides and/or nitrides,have drawn significant attention recently for electrochemical energy storage,owing to their unique physical and chemical properties.The extraordinary electronic conductivity,compositional diversity,expandable crystal structure,superior hydrophilicity,and rich surface chemistries make MXenes promising materials for electrode and other components in rechargeable batteries.This report especially focuses on the recent MXene applications as novel electrode materials and functional separator modifiers in rechargeable batteries beyond lithium.In particular,we highlight the recent advances of surface and structure engineering strategies for improving the electrochemical performance of the MXene-based materials,including surface termination modifications,heteroatom doping strategies,surface coating,interlayer space changes,nanostructure engineering,and heterostructures and secondary materials engineering.Finally,perspectives for building future sustainable rechargeable batteries with MXenes and MXene-based composite materials are presented based upon material design and a fundamental understanding of the reaction mechanisms.展开更多
In this review,we surveyed the significance of local structure engineering on electrocatalysts and electrodes for the performance of oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).Both on...In this review,we surveyed the significance of local structure engineering on electrocatalysts and electrodes for the performance of oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).Both on precious metal catalysts(PMC)and non-precious metal catalysts(NPMC),the main methods to modulate local structure of active sites have been summarized.By change of atomic coordination,modulation of bonding distortion and synergy effect from hierarchical structure,local structure engineering has influence on the intrinsic activity and stability of electrocatalysts.Moreover,we emphasized the intimate correlation between lyophobicity of electrocatalysts and membrane electrodes by local structure engineering.Our review aimed to inspire the exploration of advanced electrocatalysts and mechanism study for PEMFCs based on local structure engineering.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22472071,21832005,22072168,22002175)the Natural Science Foundation of Gansu Province(No.21JR7RA440)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA21061011)。
文摘Constrained by severe bulk charge recombination,the actual photocurrent density of tantalum nitride(Ta_(3)N_(5))photoanode is much lower than the theoretical maximum value.Herein,we report the doping of phosphorus,a non-metallic element distinct from oxygen,into Ta_(3)N_(5),resulting in a photocurrent density 9 times higher than that of pristine Ta_(3)N_(5).Systematic characterization reveals that the phosphorus doping simultaneously enhances the bulk charge separation efficiency and surface charge injection efficiency of Ta_(3)N_(5),and induces favorable band energy restructuring.Specifically,a type-II homojunction formed between phosphorus-doped near-surface region and bulk Ta_(3)N_(5) effectively promotes the separation and transfer of photogenerated holes and electrons.Further modification with a Ni Fe-based cocatalyst enables the optimized photoanode to deliver a photocurrent density of 10 mA/cm^(2) at 1.23 V versus the reversible hydrogen electrode(RHE)and an applied bias photo-to-current efficiency of 1.78%at 0.95 V versus RHE.Our work provides a foundation for the development of a broader range of non-metal doped semiconductors.
基金This work was supported by the National Natural Sci- ence Foundation of China （No.11034006, No.21273208, and No.21473168）, the Anhui Provincial Natural Sci- ence Foundation （No.1408085QB26）, the hmdamental Research Funds for the Central Universities, the China Postdoctoral Science Foundation （No.2012M511409）, and the Supercomputing Center of Chinese Academy of Sciences, Shanghai and USTC Supercomputer Cen- ters.
文摘Doping with various impurities is an effective approach to improve the photoelectrochemical properties of TiO2. Here, we explore the effect of oxygen vacancy on geometric and elec- tronic properties of compensated （i.e. V-N and Cr-C） and non-compensated （i.e. V-C and Cr-N） codoped anatase TiO2 by performing extensive density functional theory calculations. Theoretical results show that oxygen vacancy prefers to the neighboring site of metal dopant （i.e. V or Cr atom）. After introduction of oxygen vacancy, the unoccupied impurity bands located within band gap of these codoped TiO2 will be filled with electrons, and the posi- tion of conduction band offset does not change obviously, which result in the reduction of photoinduced carrier recombination and the good performance for hydrogen production via water splitting. Moreover, we find that oxygen vacancy is easily introduced in V-N codoped TiO2 under O-poor condition. These theoretical insights are helpful for designing codoped TiO2 with high photoelectrochemical performance.
基金support from Australian Research Council (ARC, FT150100450, IH150100006 and CE170100039)support from the MCATM and the FLEET+1 种基金the support from Shenzhen Nanshan District Pilotage Team Program (LHTD20170006)support from Guangzhou Science and Technology Program (Grant No. 201804010322)
文摘Metal halide perovskite nanostructures have emerged as low-dimensional semiconductors of great significance in many fields such as photovoltaics,photonics,and optoelectronics.Extensive efforts on the controlled synthesis of perovskite nanostructures have been made towards potential device applications.The engineering of their band structures holds great promise in the rational tuning of the electronic and optical properties of perovskite nanostructures,which is one of the keys to achieving efficient and multifunctional optoelectronic devices.In this article,we summarize recent advances in band structure engineering of perovskite nanostructures.A survey of bandgap engineering of nanostructured perovskites is firstly presented from the aspects of dimensionality tailoring,compositional substitution,phase segregation and transition,as well as strain and pressure stimuli.The strategies of electronic doping are then reviewed,including defect-induced self-doping,inorganic or organic molecules-based chemical doping,and modification by metal ions or nanostructures.Based on the bandgap engineering and electronic doping,discussions on engineering energy band alignments in perovskite nanostructures are provided for building high-performance perovskite p-n junctions and heterostructures.At last,we provide our perspectives in engineering band structures of perovskite nanostructures towards future low-energy optoelectronics technologies.
基金financially supported by the National Natural Science Foundation of China(Nos.52075351 and 51604177)the National Key Research and Development Program of China(No.2019YFA0705701)+4 种基金the Major S&T Infrastructure Construction Project of Sichuan Province(No.2020-510000-73-01-441847)the International S&T Innovation Cooperation Program of Sichuan Province(No.2020YFH0039)Chengdu International S&T Cooperation Funded Project(Nos.2020-GH02-00006-HZ and 2022-GH02-00027-HZ)the"1000 Talents Plan"of Sichuan Provincethe Talent Introduction Program of Sichuan University(No.YJ201410)。
文摘Although lithium-sulfur batteries are one of the favorable candidates for next-generation energy storage devices,a few key challenges that have not been addressed have limited its commercialization.These challenges include lithium dendrite growth in the anode side,volume change of the active material,poor electrical conductivity,dissolution and migration of poly sulfides,and slow rate of solid-state reactions in the cathode side.Since the electrochemical performance of lithium-sulfur batteries is greatly affected by the design of the cathode host material,it has also been widely discussed in addressing the abovementioned issues.In this paper,three design ideas of cathode host materials in terms of microstructure,crystal structure and electronic structure are introduced and summarized.Crucially,the current progress of these three structural design strategies and their effects on the electrochemical performance of lithium-sulfur batteries are discussed in detail.Finally,future directions in the structural design of cathode materials for lithium-sulfur batteries are discussed and further perspectives are provided.
基金This work was supported by the National Natural Science Foundation of China(52372289,52102368,52072192 and 51977009)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020SA001515110905).
文摘The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance.
基金support from the National Natural Science Foundation of China(Grant No.11725418)the National Key Research and Development Program of China(Grant No.2016YFA0301004)+3 种基金Science Challenge Project,China(Grant No.TZ2016004)Beijing Advanced Innovation Center for Future Chip(ICFC)Tsinghua University Initiative Scientific Research Programfunded by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)–TRR 173–268565370(projects A02)。
文摘Artificially constructed van der Waals heterostructures(vdWHs)provide an ideal platform for realizing emerging quantum phenomena in condensed matter physics.Two methods for building vdWHs have been developed:stacking two-dimensional(2D)materials into a bilayer structure with different lattice constants,or with different orientations.The interlayer coupling stemming from commensurate or incommensurate superlattice pattern plays an important role in vdWHs for modulating the band structures and generating new electronic states.In this article,we review a series of novel quantum states discovered in two model vdWH systems—graphene/hexagonal boron nitride(hBN)hetero-bilayer and twisted bilayer graphene(tBLG),and discuss how the electronic structures are modified by such stacking and twisting.We also provide perspectives for future studies on hetero-bilayer materials,from which an expansion of 2D material phase library is expected.
文摘With the continuous development of urbanization construction, rail transit has received more and more attention. For the current subway station, the main structure of open-cut subway station plays an important role in it. Therefore, the leakage problem with high frequency should be analyzed in time and dealt with reasonably. In this paper, the construction technology of leakage treatment for the main structure of open-cut subway station is analyzed for reference.
文摘Architectural structure engineering occupies a major position in architectural engineering and has a direct impact on the design quality of the whole building. As far as architectural structure design is concerned, safety and durability have received more and more attention, which are also the two major focuses of current architectural structure engineering design. However, there are still some problems in carrying out these two tasks, which greatly affect the final construction quality. This paper studies the durability and safety of building structure engineering, hoping to effectively improve the overall design quality of building structure and meet the living needs.
文摘The construction project in the actual construction process, in order to comprehensively ensure the construction quality, we should strengthen the importance of the main design of the building, and through the application of standardized construction technology, reasonable control of the construction progress and quality, to ensure the smooth progress of the follow-up work. Based on this, this paper mainly around the importance of the construction of the main structure of the building to launch an analysis, elaborated the technical application countermeasures.
文摘It is not difficult to find out that cracks in concrete structural engineering are ubiquitous. Because the damage of the structure often begins with cracks, it brings harm and risk to social production and life. Especially with the rapid development of my country's capital construction in recent decades, it is very necessary to understand and solve the ancient and novel problem of cracks in concrete structures. With the exploration and research of long-term engineering practice, with the continuous development of technology and productivity, people have realized that the generation of harmful cracks can be controlled through effective technical means. That is to say, through the organic combination of design and construction, the influence of cracks can be prevented from being harmful.
基金supported by the National Natural Science Foundation of China(U24A20566)the Joint Funding Key Projects for Science and Technology Research of Henan Province in 2023(235200810018)+1 种基金the Key R&D and Promotion Project of Henan Province(242102241028)the Natural Science Foundation of Sichuan Province(2023NSFSC0960)。
文摘Vacancy engineering is highly effective in optimizing the electrochemical performance of transition-metal selenide anodes for sodium-ion batteries.However,traditional construction strategies face the problems of low vacancy stability,additional internal structure destruction for the host material,limited vacancy content and a complicated preparation process with high energy consumption.Here we for the first time demonstrated that an aligned carbon matrix with the abundant low-tortuosity channels is capable of effectively inducing the formation of abundant selenium vacancies in the transition-metal selenide anode,meanwhile existing stably throughout its long-term cycle process.Benefiting from the advantage that abundant selenium vacancies with high stability can continuously restrain the polyselenides dissolution in the electrolyte,the prepared anode exhibits significantly improved cycling stability.Meanwhile,the fast mass and charge transport allowed by both the abundant aligned straight channels and selenium vacancies also promise it an exceptionally excellent rate capability with an ultrahigh capacity retention of 95.1%when increasing the current density from 8 to 16 A g^(-1).Impressively,it also accomplishes a remarkable fast-charging performance with about 90 s for continuous 500 cycles at up to 16 A g^(-1),accompanied with the high-rate capacity of 417.7 mAh g^(-1)and capacity retention above 92%.This work may bring a paradigm shift in the traditional selenium-deficient modulation strategy to carbon matrix structure engineering for functionalizing transition-metal selenides.
基金supported by the Key Scientific Research Project of Colleges and Universities in Henan Province(No.22A150012)the Key Scientific and Technological Project of Henan Province(no.212102311071).
文摘Achieving high performance electronic structure engineering in multi-component photocatalysts to effectively coordinate photoinduced carrier migration and surface reaction dynamics is still a key obstacle for solar-driven hydrogen production.Herein,well-defined ZnIn_(2)S_(4) nanosheets modified with metallic 1T-phase WS_(2) and Ni_(2)P dual cocatalysts with superior photoactivity and stability were fabricated by twostep ultrasonic self-assembly processes.A series of photoelectrochemical characterization studies revealed that the metallic phase 1T-WS_(2) with excellent conductivity can effectively lower the charge transport resistance and enhance electron transfer efficiency,while Ni_(2)P with abundant active sites can efficiently promote the surface H_(2)-production reaction dynamics in this dual cocatalyst system.Moreover,the synergistic effects of the 1T-WS_(2) and Ni_(2)P dual cocatalysts can boost the oxidation efficiency of the sacrificial regents(lactic acid)by elevating the valence band levels of ZnIn_(2)S_(4),which in turn promotes the separation of photocarriers.As a result,the optimized tandem Ni_(2)P/1T-WS_(2)/ZnIn_(2)S_(4) ternary heterojunction with a cascade electron transfer pathway achieved a peak hydrogen generation rate of 17.01 mmol g^(-1) h^(-1),roughly 3.34,1.56 and 1.36 times greater than those of bare ZnIn_(2)S_(4),binary 1T-WS_(2)/ZnIn_(2)S_(4) and Ni_(2)P/ZnIn_(2)S_(4),respectively.This work not only provides mechanistic insights into how dual cocatalysts influence electronic structure engineering and charge transfer dynamics but also establishes a versatile framework for the design of multi-component heterojunctions for more efficient and sustainable solarto-fuel conversion.
基金supported by the Zhejiang Provincial Natural Science Foundation of China under Grant No.LTGG23E080001Zhejiang Engineering Research Center of Intelligent Urban Infrastructure under Grant No.IUI2022-ZD-01.
文摘Kinked rebar is a special type of steel material,which is installed in beam column nodes and frame beams.It effectively enhances the blast resilience,seismic collapse resistance,and progressive collapse resistance of reinforced concrete(RC)structures without imposing substantial cost burdens,thereby emerging as a focal point of recent research endeavors.On the basis of explaining the working principle of kinked rebars,this paper reviews the research status of kinked rebars at home and abroad from three core domains:the tensile mechanical properties of kinked rebars,beam column nodes with kinked rebars,and concrete frame structures with kinked rebars.The analysis underscores that the straightening process of kinked rebars does not compromise their ultimate strength but significantly bolsters structural ductility and enhances energy dissipation capabilities.In beam-column joints,the incorporation of kinked rebars facilitates the seamless transfer of plastic hinges,adhering to the design principle of“strong columns and weak beams.”In addition,kinked rebars can greatly improve the resistance of the beam;The seismic resistance,internal explosion resistance,and progressive collapse resistance of reinforced concrete frame structures with kinked rebar have significantly improved.Beyond its primary application,the principle of kinked rebar was extended to other applications of kinked materials such as corrugated steel plates and origami structures,and the stress characteristics of related components and structures were studied.Intriguingly,this paper also proposes the application of kinked rebars in bridge engineering,aiming to address the challenges of localized damage concentration and excessive residual displacement in RC bridge piers.The introduction of kinked rebars in piers is envisioned to mitigate these issues,with the paper outlining its advantages and feasibility,thereby offering valuable insights for future research on kinked reinforcement and seismic design strategies for bridges.
基金supported by the National Key R&D Program of China(No.2021YFB1715000)the National Natural Science Foundation of China(No.52375073)。
文摘The Reliability-Based Design Optimization(RBDO)of complex engineering structures considering uncertainties has problems of being high-dimensional,highly nonlinear,and timeconsuming,which requires a significant amount of sampling simulation computation.In this paper,a basis-adaptive Polynomial Chaos(PC)-Kriging surrogate model is proposed,in order to relieve the computational burden and enhance the predictive accuracy of a metamodel.The active learning basis-adaptive PC-Kriging model is combined with a quantile-based RBDO framework.Finally,five engineering cases have been implemented,including a benchmark RBDO problem,three high-dimensional explicit problems,and a high-dimensional implicit problem.Compared with Support Vector Regression(SVR),Kriging,and polynomial chaos expansion models,results show that the proposed basis-adaptive PC-Kriging model is more accurate and efficient for RBDO problems of complex engineering structures.
文摘With the rapid development of science and technology,the application of intelligent technology in the field of civil engineering is more extensive,especially in the safety evaluation and management of engineering structures.This paper discusses the role of intelligent technologies(such as artificial intelligence,Internet of Things,BIM,big data analysis,etc.)in the monitoring,evaluation,and maintenance of engineering structure safety.By studying the principle,application scenarios,and advantages of intelligent technology in structural safety evaluation,this paper summarizes how intelligent technology can improve engineering management efficiency and reduce safety risks,and puts forward the trend and challenge of future development.
基金the financial support from International Society of Engineering Science and Technology(ISEST)UK。
文摘The conversion of carbon dioxide(CO_(2))into hydrocarbons through electrochemical CO_(2)reduction reaction(eCO_(2)RR)shows a promising method to reduce CO_(2)levels and decrease reliance on fossil fuels in the years to come.Copper-based electrocatalysts exhibit a pronounced inclination for C-C coupling,drawing considerable interest as a favored metal catalyst for generating C_(2+)products through CO_(2)RR.However,CO_(2)RR still has some obstacles including product selectivity,higher overpotential,low Faradic efficiency(FE),stability,and current density(CD).Therefore,advancement in this field enables us to comprehend the complex multi-proton electron transfer during C-C coupling and engineering strategies to improve FE and CD.Herein,this review presents some key features of Cu-based catalysts as an electrocatalyst for C_(2) product formation while addressing the industrial challenges that hinder commercialization of CO_(2)RR.In addition,recent strategies on Cu-based catalysts,synthesis strategies,advanced characterizations,and mechanistic investigations via theoretical simulations have been presented.Furthermore,recent approaches towards the composition,oxidation states,and active facets have been presented.Thus,the most favorable mechanism and possible pathways to synthesize C_(2+)products have been explained using theoretical calculations.
基金supported by the Science and Technology Plan of Fujian Provincial,China(2022G02020 and 2022H6002)the Collaborative Innovation Platform Project for Advanced Electrochemical Energy Storage Technology,Fuxiaquan National Independent Innovation Demonstration Zone,China(3502ZCQXT2022001)+1 种基金the Significant Science and Technology Project of Xiamen(the Future Industrial Area),China(3502Z20231058)the Scientific Research Startup Funding for Special Professor of Minjiang Scholars。
文摘Silicon(Si)-based anodes have emerged as promising candidates for the next-generation lithium-ion batteries(LIBs)due to their high theoretical capacity(4200 mAh g^(-1)).However,their further application is hindered by critical challenges,including severe volume expansion(~300%),formation of unstable solid electrolyte interphase(SEI),and inherently low conductivity.While extensive research has sought to alleviate the substantial internal stress caused by volume expansion through the rational design of Si-based anode structures,the underlying mechanisms that govern these improvements remain insufficiently understood,leaving significant gaps in mechanical and interface electrical failure.To build a comprehensive understanding relationship between structural design and performance enhancement of Si-based anodes,this review first analyzes the characteristics of various Sibased anode structures and their associated internal stresses.Subsequently,it summarizes effective strategies to optimize the performance of Si-based anodes,including doping design,novel electrolyte design,and fu nctional binder design.Additionally,we assess emerging technologies with high commercial potential for structural design and interfacial modification,such as porous carbon carriers,chemical vapor deposition(CVD),spray granulation,and pre-lithiation.Finally,this work provides perspectives on the structural design of Si-based anodes.Overall,this review systematically summarizes modification strategies for Si-based anodes through structural regulation and interface engineering,thereby providing a foundation for advanced structural and interfacial design.
基金supported by the National Natural Science Foundation of China(61805044,62004071 and 11674310)the Key Platforms and Research Projects of Department of Education of Guangdong Province(2018KTSCX050)+1 种基金Guangdong Provincial Key Laboratory of Information Photonics Technology(2020B121201011)"The Pearl River Talent Recruitment Program"(2019ZT08X639)。
文摘The widespread application of photodetectors has triggered an urgent need for high-sensitivity and polarization-dependent photodetection.In this field,the two-dimensional(2D)tungsten disulfide(WS_(2))exhibits intriguing optical and electronic properties,making it an attractive photosensitive material for optoelectronic applications.However,the lack of an effective built-in electric field and photoconductive gain mechanism in 2D WS_(2)impedes its application in high-performance photodetectors.Herein,we propose a hybrid heterostructure photodetector that contains 1D Te and 2D WS_(2).In this device,1D Te induces in-plane strain in 2D WS_(2),which regulates the electronic structures of local WS_(2)and gives rise to type-Ⅱ band alignment in the horizontal direction.Moreover,the vertical heterojunction built of 2D WS_(2)and 1D Te introduces a high photoconductive gain.Benefiting from these two effects,the transfer of photogenerated carriers is optimized,and the proposed photodetector exhibits high sensitivity(photoresponsivity of ~27.7 A W^(-1),detectivity of 9.5×10^(12)Jones,and short rise/decay time of 19.3/17.6 ms).In addition,anisotropic photodetection characteristics with a dichroic ratio up to 2.1 are achieved.This hybrid 1D/2D heterostructure overcomes the inherent limitations of each material and realizes novel properties,opening up a new avenue towards constructing multifunctional optoelectronic devices.
基金support by the Australian Research Council(ARC)through the ARC Discovery Projects(DP210101389 and DP230101579)the ARC Research Hub for Integrated Energy Storage Solutions(IH180100020).
文摘With the rapid growth in renewable energy,researchers worldwide are trying to expand energy storage technologies.The development of beyond-lithium battery technologies has accelerated in recent years,amid concerns regarding the sustainability of battery materials.However,the absence of suitable high-performance materials has hampered the development of the next-generation battery systems.MXenes,a family of 2D transition metal carbides and/or nitrides,have drawn significant attention recently for electrochemical energy storage,owing to their unique physical and chemical properties.The extraordinary electronic conductivity,compositional diversity,expandable crystal structure,superior hydrophilicity,and rich surface chemistries make MXenes promising materials for electrode and other components in rechargeable batteries.This report especially focuses on the recent MXene applications as novel electrode materials and functional separator modifiers in rechargeable batteries beyond lithium.In particular,we highlight the recent advances of surface and structure engineering strategies for improving the electrochemical performance of the MXene-based materials,including surface termination modifications,heteroatom doping strategies,surface coating,interlayer space changes,nanostructure engineering,and heterostructures and secondary materials engineering.Finally,perspectives for building future sustainable rechargeable batteries with MXenes and MXene-based composite materials are presented based upon material design and a fundamental understanding of the reaction mechanisms.
基金This work was supported by the National Basic Research Program of China(2017YFA0206702)the National Natural Science Foundation of China(21925110,21890751,91745113)+2 种基金Fundamental Research Funds for the Central Universities(WK 2060190084)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB36000000)the Major/Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology.
文摘In this review,we surveyed the significance of local structure engineering on electrocatalysts and electrodes for the performance of oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).Both on precious metal catalysts(PMC)and non-precious metal catalysts(NPMC),the main methods to modulate local structure of active sites have been summarized.By change of atomic coordination,modulation of bonding distortion and synergy effect from hierarchical structure,local structure engineering has influence on the intrinsic activity and stability of electrocatalysts.Moreover,we emphasized the intimate correlation between lyophobicity of electrocatalysts and membrane electrodes by local structure engineering.Our review aimed to inspire the exploration of advanced electrocatalysts and mechanism study for PEMFCs based on local structure engineering.
