The growing global energy demand and worsening climate change highlight the urgent need for clean,efficient and sustainable energy solutions.Among emerging technologies,atomically thin two-dimensional(2D)materials off...The growing global energy demand and worsening climate change highlight the urgent need for clean,efficient and sustainable energy solutions.Among emerging technologies,atomically thin two-dimensional(2D)materials offer unique advantages in photovoltaics due to their tunable optoelectronic properties,high surface area and efficient charge transport capabilities.This review explores recent progress in photovoltaics incorporating 2D materials,focusing on their application as hole and electron transport layers to optimize bandgap alignment,enhance carrier mobility and improve chemical stability.A comprehensive analysis is presented on perovskite solar cells utilizing 2D materials,with a particular focus on strategies to enhance crystallization,passivate defects and improve overall cell efficiency.Additionally,the application of 2D materials in organic solar cells is examined,particularly for reducing recombination losses and enhancing charge extraction through work function modification.Their impact on dye-sensitized solar cells,including catalytic activity and counter electrode performance,is also explored.Finally,the review outlines key challenges,material limitations and performance metrics,offering insight into the future development of nextgeneration photovoltaic devices encouraged by 2D materials.展开更多
Perovskite solar cells(PSCs)have developed rapidly,positioning them as potential candidates for nextgeneration renewable energy sources.However,conventional trial-and-error approaches and the vast compositional parame...Perovskite solar cells(PSCs)have developed rapidly,positioning them as potential candidates for nextgeneration renewable energy sources.However,conventional trial-and-error approaches and the vast compositional parameter space continue to pose challenges in the pursuit of exceptional performance and high stability of perovskite-based optoelectronics.The increasing demand for novel materials in optoelectronic devices and establishment of substantial databases has enabled data-driven machinelearning(ML)approaches to swiftly advance in the materials field.This review succinctly outlines the fundamental ML procedures,techniques,and recent breakthroughs,particularly in predicting the physical characteristics of perovskite materials.Moreover,it highlights research endeavors aimed at optimizing and screening materials to enhance the efficiency and stability of PSCs.Additionally,this review highlights recent efforts in using characterization data for ML,exploring their correlations with material properties and device performance,which are actively being researched,but they have yet to receive significant attention.Lastly,we provide future perspectives,such as leveraging Large Language Models(LLMs)and text-mining,to expedite the discovery of novel perovskite materials and expand their utilization across various optoelectronic fields.展开更多
The latest developments in bio-inspired neuromorphic vision sensors can be summarized in 3 keywords:smaller,faster,and smarter.(1)Smaller:Devices are becoming more compact by integrating previously separated component...The latest developments in bio-inspired neuromorphic vision sensors can be summarized in 3 keywords:smaller,faster,and smarter.(1)Smaller:Devices are becoming more compact by integrating previously separated components such as sensors,memory,and processing units.As a prime example,the transition from traditional sensory vision computing to in-sensor vision computing has shown clear benefits,such as simpler circuitry,lower power consumption,and less data redundancy.(2)Swifter:Owing to the nature of physics,smaller and more integrated devices can detect,process,and react to input more quickly.In addition,the methods for sensing and processing optical information using various materials(such as oxide semiconductors)are evolving.(3)Smarter:Owing to these two main research directions,we can expect advanced applications such as adaptive vision sensors,collision sensors,and nociceptive sensors.This review mainly focuses on the recent progress,working mechanisms,image pre-processing techniques,and advanced features of two types of neuromorphic vision sensors based on near-sensor and in-sensor vision computing methodologies.展开更多
With the increasing spotlight in electric vehicles,there is a growing demand for high-energy-density batteries to enhance driving range.Consequently,several studies have been conducted on high-energy-density LiNi_(x)C...With the increasing spotlight in electric vehicles,there is a growing demand for high-energy-density batteries to enhance driving range.Consequently,several studies have been conducted on high-energy-density LiNi_(x)Co_(y)Mn_(z)O_(2)cathodes.However,there is a limit to permanent performance deterioration because of side reactions caused by moisture in the atmosphere and continuous microcracks during cycling as the Ni content to express high energy increases and the content of Mn and Co that maintain structural and electrochemical stabilization decreases.The direct modification of the surface and bulk regions aims to enhance the capacity and long-term performance of high-Ni cathode materials.Therefore,an efficient modification requires a study based on a thorough understanding of the degradation mechanisms in the surface and bulk region.In this review,a comprehensive analysis of various modifications,including doping,coating,concentration gradient,and single crystals,is conducted to solve degradation issues along with an analysis of the overall degradation mechanism occurring in high-Ni cathode materials.It also summarizes recent research developments related to the following modifications,aims to provide notable points and directions for post-studies,and provides valuable references for the commercialization of stable high-energy-density cathode materials.展开更多
Achieving high-quality perovskite films without surface defects is regarded as a crucial target for the development of durable high-performance perovskite solar cells.Additive engineering is commonly employed to simul...Achieving high-quality perovskite films without surface defects is regarded as a crucial target for the development of durable high-performance perovskite solar cells.Additive engineering is commonly employed to simultaneously control the growth of perovskite crystals and passivate defects.Here,4-(trifluoromethyl)benzoic anhydride(4-TBA)composed of benzene rings functionalized with carbonyl and trifluoromethyl groups was used as an example additive to study the characteristics of additives used for producing high-quality perovskites and controlling their surface properties.The interaction between4-TBA and perovskite precursor materials was investigated using density functional theory(DFT)simulations.The electron-rich carbonyl group efficiently passivated the under-coordinated lead-ion defects.Additionally,hydrogen bonding between trifluoromethyl and organic cations prevents the generation of cation vacancies.Because of its intrinsic hydrophobicity,the trifluoromethyl group simultaneously improves the moisture and heat stability of the film.4-TBA serves as a universal modifier for various perovskite compositions.The power conversion efficiency(PCE)of inverted perovskite solar cells(PSCs)based on methylammonium(MA)with 4-TBA was improved from 16.15%to 19.28%.Similarly,the PCE of inverted PSCs based on a cesium formamidinium MA(CsFAMA)perovskite film increased from20.72%to 23.58%,upon addition of 4-TBA.Furthermore,the moisture and thermal stability of 4-TBAtreated films and devices was significantly enhanced,along with prolonged device performance.Our work provides guidance on selecting the structure and functional groups that are essential for surface defect passivation and the production of high-quality perovskites.展开更多
Silver paste is widely used in power electronics as a die-attach material owing to its low-temperature sinterability,high melting point,and excellent electrical and thermal conductivities in sintered joints.However,ow...Silver paste is widely used in power electronics as a die-attach material owing to its low-temperature sinterability,high melting point,and excellent electrical and thermal conductivities in sintered joints.However,owing to the mismatch in the coefficient of thermal expansion(CTE)between the joints and chip,the high Young's modulus of sintered silver hinders the mitigation of the high thermal stress generated during the operation of power modules,which increases the susceptibility of sintered joints to cracking,thereby leading to potential failure.This study developed a facile approach to synthesizing bayberry-like Ag microparticles(AgMPs)through the in situ assembly of silver nanorods,resulting in a uniform distribution of nanoscale structures and mesopores on the particle surface.These particles exhibited a high specific surface area of 2.5389 m^(2)·g^(-1),which enhanced theirsintering activity,enabling sintering to occur at 149.7℃.Furthermore,the porous structure of the AgMPs effectively reduced the density of joints formed by sintering AgMP paste,thereby lowering the Young's modulus of the joints.The small grain size and intricate internal substructure of the joints yielded high shear strength,which reached112.50 MPa at 250℃.The Young's modulus could be adjusted,and the pores provided by the AgMPs maintained the Young's modulus within a low range(15.11-29.61GPa),effectively mitigating thermal stress.These new bayberry-like porous AgMPs offer a promising option for die-attach materials in electronic packaging.展开更多
The bandgap is a key parameter for understanding and designing hybrid perovskite material properties,as well as developing photovoltaic devices.Traditional bandgap calculation methods like ultravioletvisible spectrosc...The bandgap is a key parameter for understanding and designing hybrid perovskite material properties,as well as developing photovoltaic devices.Traditional bandgap calculation methods like ultravioletvisible spectroscopy and first-principles calculations are time-and power-consuming,not to mention capturing bandgap change mechanisms for hybrid perovskite materials across a wide range of unknown space.In the present work,an artificial intelligence ensemble comprising two classifiers(with F1 scores of 0.9125 and 0.925)and a regressor(with mean squared error of 0.0014 eV)is constructed to achieve high-precision prediction of the bandgap.The bandgap perovskite dataset is established through highthroughput prediction of bandgaps by the ensemble.Based on the self-built dataset,partial dependence analysis(PDA)is developed to interpret the bandgap influential mechanism.Meanwhile,an interpretable mathematical model with an R^(2)of 0.8417 is generated using the genetic programming symbolic regression(GPSR)technique.The constructed PDA maps agree well with the Shapley Additive exPlanations,the GPSR model,and experiment verification.Through PDA,we reveal the boundary effect,the bowing effect,and their evolution trends with key descriptors.展开更多
Although hot-rolled La(Fe,Co,Si)13-based alloys are promising magnetocaloric materials for solidstate cooling with near-net shaping capabilities,their underlying hot deformation mechanisms remain largely unexplored.In...Although hot-rolled La(Fe,Co,Si)13-based alloys are promising magnetocaloric materials for solidstate cooling with near-net shaping capabilities,their underlying hot deformation mechanisms remain largely unexplored.In this study,a comprehensive and systematic investigation was conducted,by encompassing the analysis of hot deformation mechanisms,along with the microstructure evolution and magnetoc aloric properties of hot-rolled La-Fe-Co-Si alloy.The La_(1.05)Fe_(11.2)Co_(0.7)Si_(1.38)alloy was examined using multiscale mechanical analysis to assess the effects of temperature.A series of macroscale hot compression and microscale nanoindentation tests were performed to access global and local mechanical properties,including variations in hardness and indentation modulus of the primaryα-Fe and secondary 1:1:1 phases up to 800℃.A significant decrease in hardness and elastic recovery of the secondary phase was observed between 600and 800℃,above half of its melting point(1113℃),suggesting pronounced flow softening in both theα-Fe and 1:1:1 phases.Additionally,a novel multi-step annealing process was introduced for hot-rolled La-Fe-Co-Si alloys,involving partial transient liquid-phase diffusion in the 1:1:1 phase to address deformation-induced defects,such as residualα-Fe and lattice distortions in the 1:13 phase,which have not been previously reported.As a result,a primary La(Fe,Co,Si)13phase with a volume fraction of97.5%was achieved after multi-step annealing,compared to 87.5%using conventional annealing.Correspondingly,the magnetocaloric properties were restored,with the Curie temperature(TC)recovering from 276 to 268 K and the maximum magnetic entropy change(ΔSM)increasing from 7.56 to 8.67 J kg^(-1)K^(-1)under a 2 T magnetic field.展开更多
The direct electrolysis of CO_(2)-captured liquid,such as bicarbonate,offers economic advantages by eliminating the CO_(2)regeneration step.However,high cell voltages remain a major barrier.Herein,we propose a new str...The direct electrolysis of CO_(2)-captured liquid,such as bicarbonate,offers economic advantages by eliminating the CO_(2)regeneration step.However,high cell voltages remain a major barrier.Herein,we propose a new strategy to build dual mass-transfer pathways for CO_(2)and ions using a carbon and anion exchange ionomer(AEI)to reduce cell voltages while achieving sufficient Faradaic efficiency(FE)for the CO_(2)reduction reaction.By optimizing the interposer materials and ratio of carbon,Ag,and AEI,sufficient FECO(57%)and low cell voltages(3.17 V)were achieved at 100 mA cm^(-2).The formation of dual masstransfer pathways in bicarbonate electrolysis was confirmed through in situ/operando visualization studies.To ensure stability,we recommend the generation of dual mass-transfer pathways using chemically and physically stable materials.Our work provides an understanding of the mass transfer in bicarbonate electrolysis and a direction for overcoming the voltage issue.展开更多
With the rise of artificial intelligence(AI),neuromorphic sensory systems that emulate the five basic human sensations including tactility,audition,olfaction,gustation,and vision have attracted significant attention.I...With the rise of artificial intelligence(AI),neuromorphic sensory systems that emulate the five basic human sensations including tactility,audition,olfaction,gustation,and vision have attracted significant attention.In particular,research on integrating sensors with artificial synapses is being carried out extensively.These studies offer valuable opportunities for making another breakthrough in AI technology,including autonomous systems,real-time monitoring systems,and human-machine interactions.In this review,we introduce promising reports of neuromorphic sensory systems.Specifically,the core sensing material,device architecture,fabrication process,and applications of the proposed systems are presented in detail.Finally,the unsolved challenges and the prospects of neuromorphic sensory systems are discussed.展开更多
This study investigates zinc’s(Zn)key role in enhancing the precipitation kinetics and refinement of Mg_(17)Al_(12)and Mg_(2)Sn phases in magnesium alloys through trace sodium(Na)additions.Magnesium alloys with varyi...This study investigates zinc’s(Zn)key role in enhancing the precipitation kinetics and refinement of Mg_(17)Al_(12)and Mg_(2)Sn phases in magnesium alloys through trace sodium(Na)additions.Magnesium alloys with varying compositions of aluminum(Al),tin(Sn),Zn,and Na were prepared and aged at 453 K.Microstructural analyses were conducted using transmission electron microscopy(TEM),scanning transmission electron microscopy(STEM),and atom probe tomography(APT).Trace additions of Na significantly enhanced the precipitation responses of both Mg_(17)Al_(12)and Mg_(2)Sn phases.When Zn was co-added with Na,as in the ATZ641N3 alloy(Mg–6Al–4Sn–1Zn–0.3Na),there was a pronounced refinement in precipitate morphology and acceleration of precipitation kinetics.The ATZ641N3 alloy achieved a peak hardness of 103 Hv at 36 hours,compared to 91 Hv at 72 hours for the ATZ641 alloy without Na.The simultaneous addition of Zn and Na led to the formation of Sn–Na–Zn particles that acted as effective nucleation sites for Mg_(2)Sn,promoting aluminum partitioning and accelerating the precipitation of Mg_(17)Al_(12)through Al-rich regions.Additionally,Zn and Na co-segregated within the Mg_(17)Al_(12)phase,reducing misfit strain caused by Zn substitution and improving precipitate stability and refinement.These findings highlight Zn’s critical role,alongside trace Na additions,in refining and accelerating the precipitation of Mg_(17)Al_(12)and Mg_(2)Sn phases,thereby enhancing the age-hardening response of magnesium alloys.展开更多
Electrides,in which anionic electrons are trapped in structural cavities,have garnered significant attention for exceptionalfunctionalities based on their low work function.In low-dimensional electrides,a strong quant...Electrides,in which anionic electrons are trapped in structural cavities,have garnered significant attention for exceptionalfunctionalities based on their low work function.In low-dimensional electrides,a strong quantum confinement of anionicelectrons leads to many interesting phenomena,but a severe chemical instability due to their open structures is one of the majordisadvantages for practical applications.Here we report that one-dimensional(1D)dititanium sulfide electride exhibits an ex-traordinary stability originating from the surface self-passivation and consequent durability in bifunctional electrocatalytic activity.Theoretical calculations identify the uniqueness of the 1D[Ti_(2)S]^(2+)·2e^(−)electride,where multiple cavities form two distinct channelstructures of anionic electrons.Combined surface structure analysis and in-situ work function measurement indicate that thenatural formation of amorphous titanium oxide surface layer in air is responsible for the remarkable inertness in water and pH-varied solutions.This makes the[Ti_(2)S]^(2+)·2e^(−)electride an ideal support for a heterogenous metal-electride hybrid catalyst,demonstrating the enhanced efficiency and superior durability in both the hydrogen evolution and oxygen reduction reactionscompared to commercial Pt/C catalysts.This study will stimulate further exploratory research for developing a chemically stableelectride in reactive conditions,evoking a strategy for a practical electrocatalyst for industrial energy conversions.展开更多
Two-dimensional (2D) materials have attracted significant attention as resistive switching materials for two-terminal non-volatile memory devices, often referred to as memristors, due to their potential for achieving ...Two-dimensional (2D) materials have attracted significant attention as resistive switching materials for two-terminal non-volatile memory devices, often referred to as memristors, due to their potential for achieving fast switching speeds and low power consumption. Their excellent gate tunability in electronic properties also enables hybrid devices combining the functionality of memory devices and transistors, with the possibility of realizing large-scale memristive crossbar arrays with high integration density. To facilitate the use of 2D materials in practical memristor applications, scalable synthesis of 2D materials with high electronic quality is critical. In addition, low-temperature integration for complementary metal oxide semiconductor (CMOS) back-end-of-line (BEOL) integration is important for embedded memory applications. Solution-based exfoliation has been actively explored as a facile, cost-effective method for the mass production and low-temperature integration of 2D materials. However, the films produced from the resulting 2D nanosheet dispersions exhibited poor electrical properties in the early stages of research, thereby hindering their use in electronic devices. Recent progress in the exfoliation process and post-processing has led to significant improvements in the electronic performance of solution-processed 2D materials, driving increased adoption of these materials in memristor research. In this review article, we provide a thorough overview of the progress and current status of memristive devices utilizing solution-processed 2D resistive switching layers. We begin by introducing the electrical characteristics and resistive switching mechanisms of memristors fabricated with conventional materials to lay the groundwork for understanding memristive behavior in 2D materials. Representative solution-based exfoliation and film formation techniques are also introduced, emphasizing the benefits of these approaches for obtaining scalable 2D material films compared to conventional methods such as mechanical exfoliation and chemical vapor deposition. Finally, we explore the electrical characteristics, resistive switching mechanisms, and applications of solution-processed 2D memristive devices, discussing their advantages and remaining challenges.展开更多
The limited charge extraction efficiency and suboptimal energy-level alignment of poly(3,4-ethylenediox ythiophene)polystyrene sulfonate(PEDOT:PSS)as a hole transport layer restrict its performance in solar cell appli...The limited charge extraction efficiency and suboptimal energy-level alignment of poly(3,4-ethylenediox ythiophene)polystyrene sulfonate(PEDOT:PSS)as a hole transport layer restrict its performance in solar cell applications.In this study,we developed effective copper-ion(Cu(Ⅱ))-modified oxyl-terminated melem two-dimensional(2D)nanodisks(Cu(Ⅱ)@OMN)that improved the performance of PEDOT:PSS as a representative hole-transport layer(HTL)in organic and perovskite solar cells.Based on theoretical calculations and experimental data,the interaction between Cu(Ⅱ)@OMN and PEDOT or PSS led to electron redistribution in PEDOT:PSS and the dissociation of PEDOT and PSS,promoting enhanced charge extraction and transfer.In addition,the work function of the Cu(Ⅱ)@OMN-PEDOT:PSS is modified to achieve a more beneficial energy-level alignment,thereby facilitating improved hole transport and inhibited nonradiative recombination.Methylammonium(MA)-based perovskite and organic binary PM6:Y6solar cells achieved power conversion efficiencies(PCEs)of 19.21% and 17.15%,respectively.These PCEs are among the highest reported for MA-based perovskite and binary PM6:Y6 organic solar cells that use 2D nanomaterial-modified PEDOT:PSS,demonstrating the potential of Cu(Ⅱ)@OMN in solar cell applications.展开更多
In our current work,AZ31 magnesium alloy foams with closed-cell were successfully fabricated by melt foaming method using Ca and CaCO3 as thickening and blowing agent,respectively.The influences of porosity and pore s...In our current work,AZ31 magnesium alloy foams with closed-cell were successfully fabricated by melt foaming method using Ca and CaCO3 as thickening and blowing agent,respectively.The influences of porosity and pore size on the quasi-static compressive properties of the foams were systematically investigated.The results showed that the yield strength,energy absorption capacity and ideality energy absorption efficiency were decreased with the increase in porosity.However,specimens with porosities of 60%,65%and 70%possessed similar total energy absorption capacity and ideality energy absorption efficiency.Meanwhile,experimental results showed that mean plateau strength of the foams was increased first and then decreased with increase in mean pore size.In addition,energy absorption capacities were almost the same in the initial stage,while the differences were obvious in the middle stage.From the engineering point of view,the specimens with mean pore size of 1.5 mm possess good combination of mean plateau strength and energy absorption characteristics under the present conditions.展开更多
ECO-Al alloys are introduced as a game-changer for the aluminum industry and it is of utmost importance to determine the role of alloying elements in their processing characteristics.In this study,the effects of Cr on...ECO-Al alloys are introduced as a game-changer for the aluminum industry and it is of utmost importance to determine the role of alloying elements in their processing characteristics.In this study,the effects of Cr on the hot deformation behavior of newly-developed ECO-7175 alloy were investigated.ECO-7175 samples with and without Cr were hot-compressed using a Gleeble simulator(temperature range of 350−500℃ and strain rates of 0.001−1 s^(−1)).The results were used to study the constitutive equations,the processing maps,and the microstructural evolution of the alloys.In Cr-containing alloy,the analysis of the deformation activation energy reveals that the rate-controlling mechanisms of the deformation change gradually from self-diffusion of Al(or diffusion of Mg in Al)to diffusion of Cr in Al by decreasing the Zener−Hollomon parameter.The analysis of the processing maps of Cr-containing alloy shows that the dynamic recrystallization(DRX)zone is limited to the deformation at high temperatures and low strain rates and expands with increasing applied strain.On the other hand,it is found that the self-diffusion of Al(or Mg in Al)is the only rate-controlling mechanism during hot deformation of Cr-free alloy in all processing conditions and its DRX zone is independent of the plastic strain.展开更多
Friction stir processing （FSP） was used to incorporate SiC particles into the matrix of A356 Al alloy to form composite material. Constant tool rotation speed of 1800 r/min and travel speed of 127 mm/min were used i...Friction stir processing （FSP） was used to incorporate SiC particles into the matrix of A356 Al alloy to form composite material. Constant tool rotation speed of 1800 r/min and travel speed of 127 mm/min were used in this study. The base metal （BM） shows the hypoeutectic Al-Si dendrite structure. The microstructure of the stir zone （SZ） is very different from that of the BM. The eutectic Si and SiC particles are dispersed homogeneously in primary Al solid solution. The thermo-mechanically affected zone （TMAZ）, where the original microstructure is greatly deformed, is characterized by dispersed eutectic Si and SiC particles aligned along the rotational direction of the tool. The hardness of the SZ shows higher value than that of the BM because some defects are remarkably reduced and the eutectic Si and SiC particles are dispersed over the SZ.展开更多
Multifunctional,flexible,and robust thin films capable of operating in demanding harsh temperature environments are crucial for various cutting-edge applications.This study presents a multifunctional Janus film integr...Multifunctional,flexible,and robust thin films capable of operating in demanding harsh temperature environments are crucial for various cutting-edge applications.This study presents a multifunctional Janus film integrating highly-crystalline Ti_(3)C_(2)T_(x) MXene and mechanically-robust carbon nanotube(CNT)film through strong hydrogen bonding.The hybrid film not only exhibits high electrical conductivity(4250 S cm^(-1)),but also demonstrates robust mechanical strength and durability in both extremely low and high temperature environments,showing exceptional resistance to thermal shock.This hybrid Janus film of 15μm thickness reveals remarkable multifunctionality,including efficient electromagnetic shielding effectiveness of 72 dB in X band frequency range,excellent infrared(IR)shielding capability with an average emissivity of 0.09(a minimal value of 0.02),superior thermal camouflage performance over a wide temperature range(−1 to 300℃)achieving a notable reduction in the radiated temperature by 243℃ against a background temperature of 300℃,and outstanding IR detection capability characterized by a 44%increase in resistance when exposed to 250 W IR radiation.This multifunctional MXene/CNT Janus film offers a feasible solution for electromagnetic shielding and IR shielding/detection under challenging conditions.展开更多
The effectiveness of photoelectrochemical(PEC)water splitting is significantly restricted by insufficient light harvesting,rapid charge recombination,and slow water reduction kinetics.Since the presence of amorphous p...The effectiveness of photoelectrochemical(PEC)water splitting is significantly restricted by insufficient light harvesting,rapid charge recombination,and slow water reduction kinetics.Since the presence of amorphous phases in the interfaces hinders the overcome of these inherent limitations,a photoelectrode must be built strategically.Herein,we artificially controlled the crystallographic orientation of indium tin oxide(ITO)to determine the orientation with the smallest lattice mismatch at the Cu_(2)O interface,thus significantly reducing the amorphous phase in the early stage of electrodeposition nucleation.The[222]/[400]mixed orientation ITO primarily exposed the{400}surface planes and accelerated charge transfer by forming an optimal interface with preferentially grown(111)oriented Cu_(2)O and minimized amorphous region.In addition,the ITO surface energy was calculated using density functional theory to theoretically verify which plane is more active for growing the photoactivation layer.The rationally designed ITO/Cu_(2)O/Al-dope Zn O/TiO_(2)/Rh-P device,with each layer serving a specific purpose,achieved a photocurrent density of 8.23 mA cm^(-2)at 0 VRHEunder AM 1.5 G illumination,providing a standard method for effective solar-to-hydrogen conversion photocathodes.展开更多
Nb tubes were fabricated through hydrostatic extrusion at extrusion ratios of 3.1 and 6.1 at ambient temperature,and then their microstructure,texture,and Vickers hardness were investigated based on electron back-scat...Nb tubes were fabricated through hydrostatic extrusion at extrusion ratios of 3.1 and 6.1 at ambient temperature,and then their microstructure,texture,and Vickers hardness were investigated based on electron back-scattered diffraction(EBSD)data.The fraction of low-angle boundaries(LABs)largely decreased with a sharp decrease in mean grain sizes after hydrostatic extrusion and was not proportional to extrusion ratios,assuming that mixed-asymmetrical junctions forming LABs dissociate at high extrusion ratios from the external stress(>981 MPa)with thermal activation by the generated heat.The correlation between grain size and Vickers hardness followed the Hall−Petch relationship despite the texture gradient of theá111ñcyclic fiber textural microstructure at low extrusion ratios and theá100ñtrue fiber textural microstructure at high extrusion ratios.The increase in hydrostatic pressure on the Nb tubes contributed to texture evolution in terms of extrusion ratios due to the difference between{110}<111>and{112}<111>components based on EBSD data.展开更多
基金supported by the IITP(Institute of Information & Communications Technology Planning & Evaluation)-ITRC(Information Technology Research Center) grant funded by the Korea government(Ministry of Science and ICT) (IITP-2025-RS-2024-00437191, and RS-2025-02303505)partly supported by the Korea Basic Science Institute (National Research Facilities and Equipment Center) grant funded by the Ministry of Education. (No. 2022R1A6C101A774)the Deanship of Research and Graduate Studies at King Khalid University, Saudi Arabia, through Large Research Project under grant number RGP-2/527/46
文摘The growing global energy demand and worsening climate change highlight the urgent need for clean,efficient and sustainable energy solutions.Among emerging technologies,atomically thin two-dimensional(2D)materials offer unique advantages in photovoltaics due to their tunable optoelectronic properties,high surface area and efficient charge transport capabilities.This review explores recent progress in photovoltaics incorporating 2D materials,focusing on their application as hole and electron transport layers to optimize bandgap alignment,enhance carrier mobility and improve chemical stability.A comprehensive analysis is presented on perovskite solar cells utilizing 2D materials,with a particular focus on strategies to enhance crystallization,passivate defects and improve overall cell efficiency.Additionally,the application of 2D materials in organic solar cells is examined,particularly for reducing recombination losses and enhancing charge extraction through work function modification.Their impact on dye-sensitized solar cells,including catalytic activity and counter electrode performance,is also explored.Finally,the review outlines key challenges,material limitations and performance metrics,offering insight into the future development of nextgeneration photovoltaic devices encouraged by 2D materials.
基金supported by the Ministry of Science and ICT(MSIT)of the Republic of Korea(00302646)supported by the National Research Foundation of Korea grant funded by the Korean Government(MSIT)(NRF-2022R1A4A1019296,1345374646,2022M3J1A1064315).
文摘Perovskite solar cells(PSCs)have developed rapidly,positioning them as potential candidates for nextgeneration renewable energy sources.However,conventional trial-and-error approaches and the vast compositional parameter space continue to pose challenges in the pursuit of exceptional performance and high stability of perovskite-based optoelectronics.The increasing demand for novel materials in optoelectronic devices and establishment of substantial databases has enabled data-driven machinelearning(ML)approaches to swiftly advance in the materials field.This review succinctly outlines the fundamental ML procedures,techniques,and recent breakthroughs,particularly in predicting the physical characteristics of perovskite materials.Moreover,it highlights research endeavors aimed at optimizing and screening materials to enhance the efficiency and stability of PSCs.Additionally,this review highlights recent efforts in using characterization data for ML,exploring their correlations with material properties and device performance,which are actively being researched,but they have yet to receive significant attention.Lastly,we provide future perspectives,such as leveraging Large Language Models(LLMs)and text-mining,to expedite the discovery of novel perovskite materials and expand their utilization across various optoelectronic fields.
基金This work was supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.NRF-2019R1A2C2002447)This research also was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(No.NRF-2014R1A6A1030419)This work also was supported by Korea Institute for Advancement of Technology(KIAT)grant funded by the Korea Government(MOTIE)(P0020967,Advanced Training Program for Smart Sensor Engineers).
文摘The latest developments in bio-inspired neuromorphic vision sensors can be summarized in 3 keywords:smaller,faster,and smarter.(1)Smaller:Devices are becoming more compact by integrating previously separated components such as sensors,memory,and processing units.As a prime example,the transition from traditional sensory vision computing to in-sensor vision computing has shown clear benefits,such as simpler circuitry,lower power consumption,and less data redundancy.(2)Swifter:Owing to the nature of physics,smaller and more integrated devices can detect,process,and react to input more quickly.In addition,the methods for sensing and processing optical information using various materials(such as oxide semiconductors)are evolving.(3)Smarter:Owing to these two main research directions,we can expect advanced applications such as adaptive vision sensors,collision sensors,and nociceptive sensors.This review mainly focuses on the recent progress,working mechanisms,image pre-processing techniques,and advanced features of two types of neuromorphic vision sensors based on near-sensor and in-sensor vision computing methodologies.
文摘With the increasing spotlight in electric vehicles,there is a growing demand for high-energy-density batteries to enhance driving range.Consequently,several studies have been conducted on high-energy-density LiNi_(x)Co_(y)Mn_(z)O_(2)cathodes.However,there is a limit to permanent performance deterioration because of side reactions caused by moisture in the atmosphere and continuous microcracks during cycling as the Ni content to express high energy increases and the content of Mn and Co that maintain structural and electrochemical stabilization decreases.The direct modification of the surface and bulk regions aims to enhance the capacity and long-term performance of high-Ni cathode materials.Therefore,an efficient modification requires a study based on a thorough understanding of the degradation mechanisms in the surface and bulk region.In this review,a comprehensive analysis of various modifications,including doping,coating,concentration gradient,and single crystals,is conducted to solve degradation issues along with an analysis of the overall degradation mechanism occurring in high-Ni cathode materials.It also summarizes recent research developments related to the following modifications,aims to provide notable points and directions for post-studies,and provides valuable references for the commercialization of stable high-energy-density cathode materials.
基金supported by a Research Grant of Pukyong National University(2023)。
文摘Achieving high-quality perovskite films without surface defects is regarded as a crucial target for the development of durable high-performance perovskite solar cells.Additive engineering is commonly employed to simultaneously control the growth of perovskite crystals and passivate defects.Here,4-(trifluoromethyl)benzoic anhydride(4-TBA)composed of benzene rings functionalized with carbonyl and trifluoromethyl groups was used as an example additive to study the characteristics of additives used for producing high-quality perovskites and controlling their surface properties.The interaction between4-TBA and perovskite precursor materials was investigated using density functional theory(DFT)simulations.The electron-rich carbonyl group efficiently passivated the under-coordinated lead-ion defects.Additionally,hydrogen bonding between trifluoromethyl and organic cations prevents the generation of cation vacancies.Because of its intrinsic hydrophobicity,the trifluoromethyl group simultaneously improves the moisture and heat stability of the film.4-TBA serves as a universal modifier for various perovskite compositions.The power conversion efficiency(PCE)of inverted perovskite solar cells(PSCs)based on methylammonium(MA)with 4-TBA was improved from 16.15%to 19.28%.Similarly,the PCE of inverted PSCs based on a cesium formamidinium MA(CsFAMA)perovskite film increased from20.72%to 23.58%,upon addition of 4-TBA.Furthermore,the moisture and thermal stability of 4-TBAtreated films and devices was significantly enhanced,along with prolonged device performance.Our work provides guidance on selecting the structure and functional groups that are essential for surface defect passivation and the production of high-quality perovskites.
基金financially supported by the National Natural Science Foundation of China(Nos.52075125 and 52105331)Guangdong Basic and Applied Basic Research Foundation(No.2023A1515010591)Shenzhen Science and Technology Innovation Committee(Nos.JCYJ20210324124203009,JSGG20201102154600003,GXWD20231130103814001,GXWD20220721182229001)
文摘Silver paste is widely used in power electronics as a die-attach material owing to its low-temperature sinterability,high melting point,and excellent electrical and thermal conductivities in sintered joints.However,owing to the mismatch in the coefficient of thermal expansion(CTE)between the joints and chip,the high Young's modulus of sintered silver hinders the mitigation of the high thermal stress generated during the operation of power modules,which increases the susceptibility of sintered joints to cracking,thereby leading to potential failure.This study developed a facile approach to synthesizing bayberry-like Ag microparticles(AgMPs)through the in situ assembly of silver nanorods,resulting in a uniform distribution of nanoscale structures and mesopores on the particle surface.These particles exhibited a high specific surface area of 2.5389 m^(2)·g^(-1),which enhanced theirsintering activity,enabling sintering to occur at 149.7℃.Furthermore,the porous structure of the AgMPs effectively reduced the density of joints formed by sintering AgMP paste,thereby lowering the Young's modulus of the joints.The small grain size and intricate internal substructure of the joints yielded high shear strength,which reached112.50 MPa at 250℃.The Young's modulus could be adjusted,and the pores provided by the AgMPs maintained the Young's modulus within a low range(15.11-29.61GPa),effectively mitigating thermal stress.These new bayberry-like porous AgMPs offer a promising option for die-attach materials in electronic packaging.
基金supported by the National Research Foundation of Korea(NRF)funded by the Korean government(MSIT)(Grant number:RS-2025-02316700,and RS-2025-00522430)the China Scholarship Council Program。
文摘The bandgap is a key parameter for understanding and designing hybrid perovskite material properties,as well as developing photovoltaic devices.Traditional bandgap calculation methods like ultravioletvisible spectroscopy and first-principles calculations are time-and power-consuming,not to mention capturing bandgap change mechanisms for hybrid perovskite materials across a wide range of unknown space.In the present work,an artificial intelligence ensemble comprising two classifiers(with F1 scores of 0.9125 and 0.925)and a regressor(with mean squared error of 0.0014 eV)is constructed to achieve high-precision prediction of the bandgap.The bandgap perovskite dataset is established through highthroughput prediction of bandgaps by the ensemble.Based on the self-built dataset,partial dependence analysis(PDA)is developed to interpret the bandgap influential mechanism.Meanwhile,an interpretable mathematical model with an R^(2)of 0.8417 is generated using the genetic programming symbolic regression(GPSR)technique.The constructed PDA maps agree well with the Shapley Additive exPlanations,the GPSR model,and experiment verification.Through PDA,we reveal the boundary effect,the bowing effect,and their evolution trends with key descriptors.
基金financially supported by the Fundamental Research Program of the Korea Institute of Materials Science(No.PNKA330)
文摘Although hot-rolled La(Fe,Co,Si)13-based alloys are promising magnetocaloric materials for solidstate cooling with near-net shaping capabilities,their underlying hot deformation mechanisms remain largely unexplored.In this study,a comprehensive and systematic investigation was conducted,by encompassing the analysis of hot deformation mechanisms,along with the microstructure evolution and magnetoc aloric properties of hot-rolled La-Fe-Co-Si alloy.The La_(1.05)Fe_(11.2)Co_(0.7)Si_(1.38)alloy was examined using multiscale mechanical analysis to assess the effects of temperature.A series of macroscale hot compression and microscale nanoindentation tests were performed to access global and local mechanical properties,including variations in hardness and indentation modulus of the primaryα-Fe and secondary 1:1:1 phases up to 800℃.A significant decrease in hardness and elastic recovery of the secondary phase was observed between 600and 800℃,above half of its melting point(1113℃),suggesting pronounced flow softening in both theα-Fe and 1:1:1 phases.Additionally,a novel multi-step annealing process was introduced for hot-rolled La-Fe-Co-Si alloys,involving partial transient liquid-phase diffusion in the 1:1:1 phase to address deformation-induced defects,such as residualα-Fe and lattice distortions in the 1:13 phase,which have not been previously reported.As a result,a primary La(Fe,Co,Si)13phase with a volume fraction of97.5%was achieved after multi-step annealing,compared to 87.5%using conventional annealing.Correspondingly,the magnetocaloric properties were restored,with the Curie temperature(TC)recovering from 276 to 268 K and the maximum magnetic entropy change(ΔSM)increasing from 7.56 to 8.67 J kg^(-1)K^(-1)under a 2 T magnetic field.
基金supported by the National Research Council of Science&Technology(NST)grant funded by the Korean government(MSIT)(CAP21011-100)Additional support was provided by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(RS-2024-00431568)institutional program funding from the Korea Institute of Science and Technology。
文摘The direct electrolysis of CO_(2)-captured liquid,such as bicarbonate,offers economic advantages by eliminating the CO_(2)regeneration step.However,high cell voltages remain a major barrier.Herein,we propose a new strategy to build dual mass-transfer pathways for CO_(2)and ions using a carbon and anion exchange ionomer(AEI)to reduce cell voltages while achieving sufficient Faradaic efficiency(FE)for the CO_(2)reduction reaction.By optimizing the interposer materials and ratio of carbon,Ag,and AEI,sufficient FECO(57%)and low cell voltages(3.17 V)were achieved at 100 mA cm^(-2).The formation of dual masstransfer pathways in bicarbonate electrolysis was confirmed through in situ/operando visualization studies.To ensure stability,we recommend the generation of dual mass-transfer pathways using chemically and physically stable materials.Our work provides an understanding of the mass transfer in bicarbonate electrolysis and a direction for overcoming the voltage issue.
基金supported by the National Research Foundation of Korea(NRF)Grant funded by the Korea Government(Ministry of Science and ICT)(No.NRF-2022R1A2C2010774)by the GRRC program of Gyeonggi Province(GRRC Sungkyunkwan 2023-B04)by Korea Institute for Advancement of Technology(KIAT)grant funded by the Korea Government(MOTIE)(P0020967,Advanced Training Program for Smart Sensor Engineers).
文摘With the rise of artificial intelligence(AI),neuromorphic sensory systems that emulate the five basic human sensations including tactility,audition,olfaction,gustation,and vision have attracted significant attention.In particular,research on integrating sensors with artificial synapses is being carried out extensively.These studies offer valuable opportunities for making another breakthrough in AI technology,including autonomous systems,real-time monitoring systems,and human-machine interactions.In this review,we introduce promising reports of neuromorphic sensory systems.Specifically,the core sensing material,device architecture,fabrication process,and applications of the proposed systems are presented in detail.Finally,the unsolved challenges and the prospects of neuromorphic sensory systems are discussed.
基金supported by the Fundamental Research Program(PNKA130)of the Korea Institute of Materials Science,Republic of Korea。
文摘This study investigates zinc’s(Zn)key role in enhancing the precipitation kinetics and refinement of Mg_(17)Al_(12)and Mg_(2)Sn phases in magnesium alloys through trace sodium(Na)additions.Magnesium alloys with varying compositions of aluminum(Al),tin(Sn),Zn,and Na were prepared and aged at 453 K.Microstructural analyses were conducted using transmission electron microscopy(TEM),scanning transmission electron microscopy(STEM),and atom probe tomography(APT).Trace additions of Na significantly enhanced the precipitation responses of both Mg_(17)Al_(12)and Mg_(2)Sn phases.When Zn was co-added with Na,as in the ATZ641N3 alloy(Mg–6Al–4Sn–1Zn–0.3Na),there was a pronounced refinement in precipitate morphology and acceleration of precipitation kinetics.The ATZ641N3 alloy achieved a peak hardness of 103 Hv at 36 hours,compared to 91 Hv at 72 hours for the ATZ641 alloy without Na.The simultaneous addition of Zn and Na led to the formation of Sn–Na–Zn particles that acted as effective nucleation sites for Mg_(2)Sn,promoting aluminum partitioning and accelerating the precipitation of Mg_(17)Al_(12)through Al-rich regions.Additionally,Zn and Na co-segregated within the Mg_(17)Al_(12)phase,reducing misfit strain caused by Zn substitution and improving precipitate stability and refinement.These findings highlight Zn’s critical role,alongside trace Na additions,in refining and accelerating the precipitation of Mg_(17)Al_(12)and Mg_(2)Sn phases,thereby enhancing the age-hardening response of magnesium alloys.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(2022M3H4A1A01010832 and RS-2024-00449682)the Basic Science Research Program through the NRF funded by the Ministry of Education(2021R1A6A1A03039696)+1 种基金Computer time allocation has been provided by the US DOE INCITE program(DE-AC02-06CH11357)National ScienceFoundation ACCESS program(NSF-2138296)。
文摘Electrides,in which anionic electrons are trapped in structural cavities,have garnered significant attention for exceptionalfunctionalities based on their low work function.In low-dimensional electrides,a strong quantum confinement of anionicelectrons leads to many interesting phenomena,but a severe chemical instability due to their open structures is one of the majordisadvantages for practical applications.Here we report that one-dimensional(1D)dititanium sulfide electride exhibits an ex-traordinary stability originating from the surface self-passivation and consequent durability in bifunctional electrocatalytic activity.Theoretical calculations identify the uniqueness of the 1D[Ti_(2)S]^(2+)·2e^(−)electride,where multiple cavities form two distinct channelstructures of anionic electrons.Combined surface structure analysis and in-situ work function measurement indicate that thenatural formation of amorphous titanium oxide surface layer in air is responsible for the remarkable inertness in water and pH-varied solutions.This makes the[Ti_(2)S]^(2+)·2e^(−)electride an ideal support for a heterogenous metal-electride hybrid catalyst,demonstrating the enhanced efficiency and superior durability in both the hydrogen evolution and oxygen reduction reactionscompared to commercial Pt/C catalysts.This study will stimulate further exploratory research for developing a chemically stableelectride in reactive conditions,evoking a strategy for a practical electrocatalyst for industrial energy conversions.
基金supported by the National Research Foundation(NRF)Grant funded by the Korean government(MSIT)(Nos.RS-2023-00208538,RS-2024-00411904,and RS-2023-00237308).
文摘Two-dimensional (2D) materials have attracted significant attention as resistive switching materials for two-terminal non-volatile memory devices, often referred to as memristors, due to their potential for achieving fast switching speeds and low power consumption. Their excellent gate tunability in electronic properties also enables hybrid devices combining the functionality of memory devices and transistors, with the possibility of realizing large-scale memristive crossbar arrays with high integration density. To facilitate the use of 2D materials in practical memristor applications, scalable synthesis of 2D materials with high electronic quality is critical. In addition, low-temperature integration for complementary metal oxide semiconductor (CMOS) back-end-of-line (BEOL) integration is important for embedded memory applications. Solution-based exfoliation has been actively explored as a facile, cost-effective method for the mass production and low-temperature integration of 2D materials. However, the films produced from the resulting 2D nanosheet dispersions exhibited poor electrical properties in the early stages of research, thereby hindering their use in electronic devices. Recent progress in the exfoliation process and post-processing has led to significant improvements in the electronic performance of solution-processed 2D materials, driving increased adoption of these materials in memristor research. In this review article, we provide a thorough overview of the progress and current status of memristive devices utilizing solution-processed 2D resistive switching layers. We begin by introducing the electrical characteristics and resistive switching mechanisms of memristors fabricated with conventional materials to lay the groundwork for understanding memristive behavior in 2D materials. Representative solution-based exfoliation and film formation techniques are also introduced, emphasizing the benefits of these approaches for obtaining scalable 2D material films compared to conventional methods such as mechanical exfoliation and chemical vapor deposition. Finally, we explore the electrical characteristics, resistive switching mechanisms, and applications of solution-processed 2D memristive devices, discussing their advantages and remaining challenges.
基金supported by the Nano Material Technology Development Program(2021M3H4A1A02057007)funded by the Ministry of Science and ICT through the National Research Foundation of Koreasupported by the Basic Science Research Program through NRF funded by the Ministry of Education(2022R1A6A1A03051158,2022R1A2C4002248,RS-202300247069)。
文摘The limited charge extraction efficiency and suboptimal energy-level alignment of poly(3,4-ethylenediox ythiophene)polystyrene sulfonate(PEDOT:PSS)as a hole transport layer restrict its performance in solar cell applications.In this study,we developed effective copper-ion(Cu(Ⅱ))-modified oxyl-terminated melem two-dimensional(2D)nanodisks(Cu(Ⅱ)@OMN)that improved the performance of PEDOT:PSS as a representative hole-transport layer(HTL)in organic and perovskite solar cells.Based on theoretical calculations and experimental data,the interaction between Cu(Ⅱ)@OMN and PEDOT or PSS led to electron redistribution in PEDOT:PSS and the dissociation of PEDOT and PSS,promoting enhanced charge extraction and transfer.In addition,the work function of the Cu(Ⅱ)@OMN-PEDOT:PSS is modified to achieve a more beneficial energy-level alignment,thereby facilitating improved hole transport and inhibited nonradiative recombination.Methylammonium(MA)-based perovskite and organic binary PM6:Y6solar cells achieved power conversion efficiencies(PCEs)of 19.21% and 17.15%,respectively.These PCEs are among the highest reported for MA-based perovskite and binary PM6:Y6 organic solar cells that use 2D nanomaterial-modified PEDOT:PSS,demonstrating the potential of Cu(Ⅱ)@OMN in solar cell applications.
基金The present authors thanks to the financial support provided by International Science&Technology Cooperation Program of China(2010DFA51850)“863”project of China(NO.2013AA031002),Major Project of China(2013ZX04004027)+3 种基金the‘100 Talents Project’of Hebei Province of China(Grant No.E2012100009)Natural Science Foundation of Hebei Province of China(No.E2012202017)Science and Technology Project of Hebei Province(13211008D)Science and Technology Research of Hebei Province for Youth fund(No.2011182).
文摘In our current work,AZ31 magnesium alloy foams with closed-cell were successfully fabricated by melt foaming method using Ca and CaCO3 as thickening and blowing agent,respectively.The influences of porosity and pore size on the quasi-static compressive properties of the foams were systematically investigated.The results showed that the yield strength,energy absorption capacity and ideality energy absorption efficiency were decreased with the increase in porosity.However,specimens with porosities of 60%,65%and 70%possessed similar total energy absorption capacity and ideality energy absorption efficiency.Meanwhile,experimental results showed that mean plateau strength of the foams was increased first and then decreased with increase in mean pore size.In addition,energy absorption capacities were almost the same in the initial stage,while the differences were obvious in the middle stage.From the engineering point of view,the specimens with mean pore size of 1.5 mm possess good combination of mean plateau strength and energy absorption characteristics under the present conditions.
文摘ECO-Al alloys are introduced as a game-changer for the aluminum industry and it is of utmost importance to determine the role of alloying elements in their processing characteristics.In this study,the effects of Cr on the hot deformation behavior of newly-developed ECO-7175 alloy were investigated.ECO-7175 samples with and without Cr were hot-compressed using a Gleeble simulator(temperature range of 350−500℃ and strain rates of 0.001−1 s^(−1)).The results were used to study the constitutive equations,the processing maps,and the microstructural evolution of the alloys.In Cr-containing alloy,the analysis of the deformation activation energy reveals that the rate-controlling mechanisms of the deformation change gradually from self-diffusion of Al(or diffusion of Mg in Al)to diffusion of Cr in Al by decreasing the Zener−Hollomon parameter.The analysis of the processing maps of Cr-containing alloy shows that the dynamic recrystallization(DRX)zone is limited to the deformation at high temperatures and low strain rates and expands with increasing applied strain.On the other hand,it is found that the self-diffusion of Al(or Mg in Al)is the only rate-controlling mechanism during hot deformation of Cr-free alloy in all processing conditions and its DRX zone is independent of the plastic strain.
基金supported by a grant from the Fundamental R & D Program (No.10038688) for Core Technology of Materials funded by the Ministry of Knowledge Economy, Republic of Korea
文摘Friction stir processing （FSP） was used to incorporate SiC particles into the matrix of A356 Al alloy to form composite material. Constant tool rotation speed of 1800 r/min and travel speed of 127 mm/min were used in this study. The base metal （BM） shows the hypoeutectic Al-Si dendrite structure. The microstructure of the stir zone （SZ） is very different from that of the BM. The eutectic Si and SiC particles are dispersed homogeneously in primary Al solid solution. The thermo-mechanically affected zone （TMAZ）, where the original microstructure is greatly deformed, is characterized by dispersed eutectic Si and SiC particles aligned along the rotational direction of the tool. The hardness of the SZ shows higher value than that of the BM because some defects are remarkably reduced and the eutectic Si and SiC particles are dispersed over the SZ.
基金supported by grants from the Basic Science Research Program(2021M3H4A1A03047327 and 2022R1A2C3006227)through the National Research Foundation of Korea,funded by the Ministry of Science,ICT,and Future Planningthe Fundamental R&D Program for Core Technology of Materials and the Industrial Strategic Technology Development Program(20020855),funded by the Ministry of Trade,Industry,and Energy,Republic of Korea+2 种基金the National Research Council of Science&Technology(NST),funded by the Korean Government(MSIT)(CRC22031-000)partially supported by POSCO and Hyundai Mobis,a start-up fund(S-2022-0096-000)the Postdoctoral Research Program of Sungkyunkwan University(2022).
文摘Multifunctional,flexible,and robust thin films capable of operating in demanding harsh temperature environments are crucial for various cutting-edge applications.This study presents a multifunctional Janus film integrating highly-crystalline Ti_(3)C_(2)T_(x) MXene and mechanically-robust carbon nanotube(CNT)film through strong hydrogen bonding.The hybrid film not only exhibits high electrical conductivity(4250 S cm^(-1)),but also demonstrates robust mechanical strength and durability in both extremely low and high temperature environments,showing exceptional resistance to thermal shock.This hybrid Janus film of 15μm thickness reveals remarkable multifunctionality,including efficient electromagnetic shielding effectiveness of 72 dB in X band frequency range,excellent infrared(IR)shielding capability with an average emissivity of 0.09(a minimal value of 0.02),superior thermal camouflage performance over a wide temperature range(−1 to 300℃)achieving a notable reduction in the radiated temperature by 243℃ against a background temperature of 300℃,and outstanding IR detection capability characterized by a 44%increase in resistance when exposed to 250 W IR radiation.This multifunctional MXene/CNT Janus film offers a feasible solution for electromagnetic shielding and IR shielding/detection under challenging conditions.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2021R1A2C3011870,2022R1A6A3A13071182)supported by the Global Research and Development Center Program(2018K1A4A3A01064272)through the NRF funded by the Korea government(MSIT)。
文摘The effectiveness of photoelectrochemical(PEC)water splitting is significantly restricted by insufficient light harvesting,rapid charge recombination,and slow water reduction kinetics.Since the presence of amorphous phases in the interfaces hinders the overcome of these inherent limitations,a photoelectrode must be built strategically.Herein,we artificially controlled the crystallographic orientation of indium tin oxide(ITO)to determine the orientation with the smallest lattice mismatch at the Cu_(2)O interface,thus significantly reducing the amorphous phase in the early stage of electrodeposition nucleation.The[222]/[400]mixed orientation ITO primarily exposed the{400}surface planes and accelerated charge transfer by forming an optimal interface with preferentially grown(111)oriented Cu_(2)O and minimized amorphous region.In addition,the ITO surface energy was calculated using density functional theory to theoretically verify which plane is more active for growing the photoactivation layer.The rationally designed ITO/Cu_(2)O/Al-dope Zn O/TiO_(2)/Rh-P device,with each layer serving a specific purpose,achieved a photocurrent density of 8.23 mA cm^(-2)at 0 VRHEunder AM 1.5 G illumination,providing a standard method for effective solar-to-hydrogen conversion photocathodes.
基金supported by a Grant from the Fundamental R&D Program(10067694)funded by the Ministry of Trade,Industry and Energy,Korea。
文摘Nb tubes were fabricated through hydrostatic extrusion at extrusion ratios of 3.1 and 6.1 at ambient temperature,and then their microstructure,texture,and Vickers hardness were investigated based on electron back-scattered diffraction(EBSD)data.The fraction of low-angle boundaries(LABs)largely decreased with a sharp decrease in mean grain sizes after hydrostatic extrusion and was not proportional to extrusion ratios,assuming that mixed-asymmetrical junctions forming LABs dissociate at high extrusion ratios from the external stress(>981 MPa)with thermal activation by the generated heat.The correlation between grain size and Vickers hardness followed the Hall−Petch relationship despite the texture gradient of theá111ñcyclic fiber textural microstructure at low extrusion ratios and theá100ñtrue fiber textural microstructure at high extrusion ratios.The increase in hydrostatic pressure on the Nb tubes contributed to texture evolution in terms of extrusion ratios due to the difference between{110}<111>and{112}<111>components based on EBSD data.
