Achieving high-energy density remains a key objective for advanced energy storage systems.However,challenges,such as poor cathode conductivity,anode dendrite formation,polysulfide shuttling,and electrolyte degradation...Achieving high-energy density remains a key objective for advanced energy storage systems.However,challenges,such as poor cathode conductivity,anode dendrite formation,polysulfide shuttling,and electrolyte degradation,continue to limit performance and stability.Molecular and ionic dipole interactions have emerged as an effective strategy to address these issues by regulating ionic transport,modulating solvation structures,optimizing interfacial chemistry,and enhancing charge transfer kinetics.These interactions also stabilize electrode interfaces,suppress side reactions,and mitigate anode corrosion,collectively improving the durability of high-energy batteries.A deeper understanding of these mechanisms is essential to guide the design of next-generation battery materials.Herein,this review summarizes the development,classification,and advantages of dipole interactions in high-energy batteries.The roles of dipoles,including facilitating ion transport,controlling solvation dynamics,stabilizing the electric double layer,optimizing solid electrolyte interphase and cathode–electrolyte interface layers,and inhibiting parasitic reactions—are comprehensively discussed.Finally,perspectives on future research directions are proposed to advance dipole-enabled strategies for high-performance energy storage.This review aims to provide insights into the rational design of dipole-interactive systems and promote the progress of electrochemical energy storage technologies.展开更多
Thick electrodes can substantially enhance the overall energy density of batteries.However,insufficient wettability of aqueous electrolytes toward electrodes with conventional hydrophobic binders severely limits utili...Thick electrodes can substantially enhance the overall energy density of batteries.However,insufficient wettability of aqueous electrolytes toward electrodes with conventional hydrophobic binders severely limits utilization of active materials with increasing the thickness of electrodes for aqueous batteries,resulting in battery performance deterioration with a reduced capacity.Here,we demonstrate that controlling the hydrophilicity of the thicker electrodes is critical to enhancing the overall energy density of batteries.Hydrophilic binders are synthesized via a simple sulfonation process of conventional polyvinylidene fluoride binders,considering physicochemical properties such as mechanical properties and adhesion.The introduction of abundant sulfonate groups of binders(i)allows fast and sufficient electrolyte wetting,and(ii)improves ionic conduction in thick electrodes,enabling a significant increase in reversible capacities under various current densities.Further,the sulfonated binder effectively inhibits the dissolution of cathode materials in reactive aqueous electrolytes.Overall,our findings significantly enhance the energy density and contribute to the development of practical zinc-ion batteries.展开更多
This study described a hydrometallurgical method to investigate the separation of rare earth elements（REEs）from rare earth polishing powder wastes（REPPWs）containing large amounts of rare earth oxides with a major ...This study described a hydrometallurgical method to investigate the separation of rare earth elements（REEs）from rare earth polishing powder wastes（REPPWs）containing large amounts of rare earth oxides with a major phase of CeO2 and minor phases of La2O3,Pr2O3,and Nd2O3 using a process devised by the authors.The suggested approach consisted of five processes：the synthesis of NaR E（SO4）2·xH2O from rare earth oxides in Na2SO4-H2SO4-H2 O solutions（Process 1）,the conversion of NaR E（SO4）2·xH2O into RE（OH）3 using NaO H（Process 2）,and the oxidation of Ce（OH）3 into Ce（OH）4 using air with O2 injection（Process 3）,followed by Processes 4 and 5 for separation of REEs by acid leaching using HCl and H2SO4,respectively.To confirm the high yield of NaR E（SO4）2·xH2O in Process 1,experiments were carried out under various Na2SO4 concentrations（0.4–2.5 mol/L）,sulfuric acid concentrations（6–14 mol/L）,and reaction temperatures（95–125 oC）.In addition,the effect of the pH value on the separation of Ce（OH）4 in HCl-H2 O solutions with Ce（OH）4,La-,Pr-,and Nd（OH）3 in Process 4 was also investigated.On the basis of above results,the possibility of effective separation of REEs from REPPWs could be confirmed.展开更多
1. Foreword Energy storage plays a key role in the transition towards a carbon-neutral economy. By balancing power grids and saving surplus energy, it represents a concrete means of improving energy efficiency and int...1. Foreword Energy storage plays a key role in the transition towards a carbon-neutral economy. By balancing power grids and saving surplus energy, it represents a concrete means of improving energy efficiency and integrating more renewable energy sources into electricity systems. A variety of technologies to store energy are developing at a fast pace and increasingly becomingmoremarketcompetitive,includingtraditional electric energy storage, thermal energy storage, and newly developed hydrogen energy storage, etc. The demand for energy storage system with high power and efficiency boosts the development in the advanced techniques and materials,such as batteries, super-capacitors, molten salts, and catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER).展开更多
The anionic redox has been widely studied in layered-oxide-cathodes in attempts to achieve highenergy-density for Na-ion batteries(NIBs).It is known that an oxidation state of Mn^(4+) or Ru^(5+) is essential for the a...The anionic redox has been widely studied in layered-oxide-cathodes in attempts to achieve highenergy-density for Na-ion batteries(NIBs).It is known that an oxidation state of Mn^(4+) or Ru^(5+) is essential for the anionic reaction of O^(2-)/O~-to occur during Na^(+) de/intercalation.However,here,we report that the anionic redox can occur in Ru-based layered-oxide-cathodes before full oxidation of Ru^(4+)/Ru^(5+).Combining studies using first-principles calculation and experimental techniques reveals that further Na^(+) deintercalation from P2-Na_(0.33)[Mg_(0.33)Ru_(0.67)]O_(2) is based on anionic oxidation after 0.33 mol Na^(+) deintercalation from P2-Na_(0.67)[Mg_(0.33)Ru_(0.67)]O_(2) with cationic oxidation of Ru^(4+)/Ru^(4.5+).Especially,it is revealed that the only oxygen neighboring 2Mg/1 Ru can participate in the anionic redox during Na^(+) de/intercalation,which implies that the Na-O-Mg arrangement in the P2-Na_(0.33)[M9_(0.33)Ru_(0.67)]O_(2) structure can dramatically lower the thermodynamic stability of the anionic redox than that of cationic redox.Through the O anionic and Ru cationic reaction,P2-Na_(0.67)[Mg_(0.33)Ru_(0.67)]O_(2) exhibits not only a large specific capacity of~172 mA h g^(-1) but also excellent power-capability via facile Na^(+) diffusion and reversible structural change during charge/discharge.These findings suggest a novel strategy that can increase the activity of anionic redox by modulating the local environment around oxygen to develop high-energy-density cathode materials for NIBs.展开更多
As part of the national strategy to further develop the wind energy sector,the eight prefectures of Upper Guinea have been selected.Using meteorological data recorded over thirty years(1991-2021)at a height of 20 m,we...As part of the national strategy to further develop the wind energy sector,the eight prefectures of Upper Guinea have been selected.Using meteorological data recorded over thirty years(1991-2021)at a height of 20 m,we assessed wind resources in terms of characteristic speeds,power and available energy.To this end,the Weibull distribution method was used and the following values were obtained:3.66 m/s for the average speed;1,102.83 W/m^(2)for the available power and 8,747.06 kWh/m^(2)/year for the annual available energy.展开更多
Seawater is the most abundant source of molecular hydrogen.Utilizing the hydrogen reserves present in the seawater may inaugurate innovative strategies aimed at advancing sustainable energy and environmental preservat...Seawater is the most abundant source of molecular hydrogen.Utilizing the hydrogen reserves present in the seawater may inaugurate innovative strategies aimed at advancing sustainable energy and environmental preservation endeavors in the future.Recently,there has been a surge in study in the field addressing the production of hydrogen through the electrochemical seawater splitting.However,the performance and durability of the electrode have limitations due to the fact that there are a few challenges that need to be addressed in order to make the technology suitable for the industrial purpose.The active site blockage caused by chloride ions that are prevalent in seawater and chloride corrosion is the most significant issue;it has a negative impact on both the activity and the durability of the anode component.Addressing this particular issue is of upmost importance in the seawater splitting area.This review concentrates on the newly developed materials and techniques for inhibiting chloride ions by blocking the active sites,simultaneously preventing the chloride corrosion.It is anticipated that the concept will be advantageous for a large audience and will inspire researchers to study on this particular area of concern.展开更多
Aluminum(Al)exhibits excellent electrical conductivity,mechanical ductility,and good chemical compatibility with high-ionic-conductivity electrolytes.This makes it more suitable as an anode material for all-solid-stat...Aluminum(Al)exhibits excellent electrical conductivity,mechanical ductility,and good chemical compatibility with high-ionic-conductivity electrolytes.This makes it more suitable as an anode material for all-solid-state lithium batteries(ASSLBs)compared to the overly reactive metallic lithium anode and the mechanically weak silicon anode.This study finds that the pre-lithiated Al anode demonstrates outstanding interfacial stability with the Li_6PS_5Cl(LPSCl)electrolyte,maintaining stable cycling for over 1200 h under conditions of deep charge-discharge.This paper combines the pre-lithiated Al anode with a high-nickel cathode,LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2),paired with the highly ionic conductive LPSCl electrolyte,to design an ASSLB with high energy density and stability.Using anode pre-lithiation techniques,along with dual-reinforcement technology between the electrolyte and the cathode active material,the ASSLB achieves stable cycling for 1000 cycles at a 0.2C rate,with a capacity retention rate of up to 82.2%.At a critical negative-to-positive ratio of 1.1,the battery's specific energy reaches up to 375 Wh kg^(-1),and it maintains over 85.9%of its capacity after 100 charge-discharge cycles.This work provides a new approach and an excellent solution for developing low-cost,high-stability all-solid-state batteries.展开更多
Rechargeable magnesium batteries are promising alternatives to traditional lithium batteries because of the high abundance of Mg compounds in earth crust,their low toxicity,and possible favorable properties as electro...Rechargeable magnesium batteries are promising alternatives to traditional lithium batteries because of the high abundance of Mg compounds in earth crust,their low toxicity,and possible favorable properties as electrodes'material.However,Mg metal anodes face several challenges,notably the natively existence of an inactive oxide layer on their surfaces,which reduces their effectiveness.Additionally,interactions of Mg electrodes with electrolyte solutions'components can lead to the formation of insulating surface layers,that can fully block them for ions transport.This review addresses these issues by focusing on surface treatments strategies to enhance electrochemical performance of Mg anodes.It highlights chemical and physical modification techniques to prevent oxidation and inactive-layers formation,as well as their practical implications for MIBs.We also examined the impact of Mg anodes'surface engineering on their electrochemical reversibility and cycling efficiency.Finally,future research directions to improve the performance and commercial viability of magnesium anodes and advance development of high-capacity,safe,and cost-effective energy storage systems based on magnesium electrochemistry are discussed.展开更多
Understanding the degradation phenomenon of proton exchange membrane fuel cells under electrochemical cycling requires an analysis of the porous carbon support structure.Key factors contributing to this phenomenon inc...Understanding the degradation phenomenon of proton exchange membrane fuel cells under electrochemical cycling requires an analysis of the porous carbon support structure.Key factors contributing to this phenomenon include changes in the total porosity and viable surface area for electrochemical reactions.Electron tomography-based serial section imaging using focused ion beam-scanning electron microscopy(FIB-SEM)can elucidate this phenomenon at a nanoscale resolution.However,this highresolution tomographic analysis requires a huge image dataset and manual inputs in rule-based workflows;these requirements are time-consuming and often cause experimental difficulties and unreliable interpretations.We propose a deep learning-empowered approach comprising a two-step automated process for image interpolation and semantic segmentation to address the practical issues encountered in FIB-SEM electron tomography.An optimally trained interpolation model can reduce the image data requirement by more than 95%to analyze the structural degradation of carbon supports after electrochemical cycling while maintaining the reliability obtained in conventional tomographic analysis with several hundred images.Because the subsequent image segmentation model excludes a complicated manual filtering process,the relevant structural parameters can be reliably measured without human bias.Our sparse-section imaging-based deep learning process can allow cost-efficient analysis and reliable measurement of the degree of cycling-induced carbon corrosion.展开更多
With electric vehicles(EVs)emerging as a primary mode of transportation,ensuring their reliable operation in harsh environments is crucial.However,lithium-ion batteries(LIBs)suffer from severe polarization at low temp...With electric vehicles(EVs)emerging as a primary mode of transportation,ensuring their reliable operation in harsh environments is crucial.However,lithium-ion batteries(LIBs)suffer from severe polarization at low temperatures,limiting their operation in cold climates.In addition,difficulties in discovering new battery materials have highlighted a growing demand for innovative electrode designs that achieve high performance,even at low temperatu res.To address this issue,we prepared a thin,resistive,and patterned carbon interlayer on the anode current collector.This carbon-patterned layer(CPL)serves as a self-heating layer to efficiently elevate the entire cell temperature,thus improving the rate capability and cyclability at low temperatures while maintaining the performance at room temperature.Furthermore,we validated the versatile applicability of CPLs to large-format LIB cells through experimental studies and electrochemo-thermal multiphysics modeling and simulations,with the results confirming 11%capacity enhancement in 21,700 cylindrical cells at a 0.5C-rate and-24℃.We expect this electrode design to offer reliable power delivery in harsh climates,thereby potentially expanding the applications of LIBs.展开更多
Composite cathodes integrating Ni-rich layered oxides and oxide solid electrolytes are essential for highenergy all-solid-state lithium-ion batteries(ASSLBs),yet interfacial degradation during high-temperature co-sint...Composite cathodes integrating Ni-rich layered oxides and oxide solid electrolytes are essential for highenergy all-solid-state lithium-ion batteries(ASSLBs),yet interfacial degradation during high-temperature co-sintering(>600℃)remains a critical challenge.While surface passivation strategies mitigate reactions below 400℃,their effectiveness diminishes at elevated temperatures due to inability to counteract Li^(+)concentration gradients.Here,we introduce in situ lithium compensators,i.e.,LiOH/Li_(2)CO_(3),into NCM-LATP composite cathodes to dynamically replenish Li^(+)during co-sintering.These additives melt to form transient Li^(+)-rich phases that back-diffuse Li^(+)into NCM lattices,suppressing layered-to-rock salt transitions and stabilizing the interface.Quasi in situ XRD confirms retention of the layered structure at temperature up to 700℃,while electrochemical tests demonstrate a reversible capacity of 222.2 mA h g^(-1)—comparable to NCM before co-sintering—and an impressive 65.3% capacity retention improvement over100 cycles.In contrast,uncompensated cathodes exhibit severe degradation to 96.5 mA h g^(-1)due to Li depletion and resistive Li-Ti-O interphases.This strategy integrates sacrificial chemistry with scalable powder-mixing workflows,achieving a 93.4% reduction in interfacial impedance.By addressing Li^(+)flux homogenization and structural stability,this work provides a practical pathway toward industrialscale fabrication of high-performance ASSLBs.展开更多
To enhance the electrochemical performance of lithium-ion battery anodes with higher silicon content,it is essential to engineer their microstructure for better lithium-ion transport and mitigated volume change as wel...To enhance the electrochemical performance of lithium-ion battery anodes with higher silicon content,it is essential to engineer their microstructure for better lithium-ion transport and mitigated volume change as well.Herein,we suggest an effective approach to control the micropore structure of silicon oxide(SiO_(x))/artificial graphite(AG)composite electrodes using a perforated current collector.The electrode features a unique pore structure,where alternating high-porosity domains and low-porosity domains markedly reduce overall electrode resistance,leading to a 20%improvement in rate capability at a 5C-rate discharge condition.Using microstructure-resolved modeling and simulations,we demonstrate that the patterned micropore structure enhances lithium-ion transport,mitigating the electrolyte concentration gradient of lithium-ion.Additionally,perforating current collector with a chemical etching process increases the number of hydrogen bonding sites and enlarges the interface with the SiO_(x)/AG composite electrode,significantly improving adhesion strength.This,in turn,suppresses mechanical degradation and leads to a 50%higher capacity retention.Thus,regularly arranged micropore structure enabled by the perforated current collector successfully improves both rate capability and cycle life in SiO_(x)/AG composite electrodes,providing valuable insights into electrode engineering.展开更多
Aqueous zinc-ion batteries(AZIBs)have garnered considerable attention as promising post-lithium energy storage technologies owing to their intrinsic safety,cost-effectiveness,and competitive gravimetric energy density...Aqueous zinc-ion batteries(AZIBs)have garnered considerable attention as promising post-lithium energy storage technologies owing to their intrinsic safety,cost-effectiveness,and competitive gravimetric energy density.However,their practical commercialization is hindered by critical challenges on the anode side,including dendrite growth and parasitic reactions at the anode/electrolyte interface.Recent studies highlight that rational electrolyte structure engineering offers an effective route to mitigate these issues and strengthen the electrochemical performance of the zinc metal anode.In this review,we systematically summarize state-of-the-art strategies for electrolyte optimization,with a particular focus on the zinc salts regulation,electrolyte additives,and the construction of novel electrolytes,while elucidating the underlying design principles.We further discuss the key structure–property relationships governing electrolyte behavior to provide guidance for the development of next-generation electrolytes.Finally,future perspectives on advanced electrolyte design are proposed.This review aims to serve as a comprehensive reference for researchers exploring high-performance electrolyte engineering in AZIBs.展开更多
Supercritical fluids(e.g.,hydrocarbon fuels,water,carbon dioxide,and organic working medium,etc)have been recognized as working media to improve thermal efficiencies in power cycles and energy conversion,and have been...Supercritical fluids(e.g.,hydrocarbon fuels,water,carbon dioxide,and organic working medium,etc)have been recognized as working media to improve thermal efficiencies in power cycles and energy conversion,and have been used or selected as the working fluids in engineering fields such as aerospace,nuclear power,solar energy,refrigeration,geothermal energy,chemical technology,and so on.To better understand the interesting characteristic or abnormal behaviors of supercritical fluids,most valuable research works(including experimental results and numerical studies)from domestic and abroad have been documented.As such,this paper presents a comprehensive review on heat transfer behaviors of some supercritical fluids in engineering applications.This review focuses on recently available articles published mainly from 2016 up to the present time.The common problems(i.e.,heat transfer enhancement and heat transfer deterioration particularly for the supercritical hydrocarbon fuels)in the supercritical field are summarized and some perspectives on future prospects are also included.展开更多
LiMnOand LiNiAlyMnO（x= 0.50;y = 0.05-0.50） powders have been synthesized via facile solgel method using Behenic acid as active cheiating agent.The synthesized samples are subjected to physical characterizations such...LiMnOand LiNiAlyMnO（x= 0.50;y = 0.05-0.50） powders have been synthesized via facile solgel method using Behenic acid as active cheiating agent.The synthesized samples are subjected to physical characterizations such as thermo gravimetric analysis（TG/DTA）,X-ray diffraction（XRD）,Fourier transform infrared spectroscopy（FT-IR）,field-emission scanning electron microscopy（FESEM）,transmission electron microscopy（TEM） and electrochemical studies viz.,galvanostatic cycling properties,electrochemical impedance spectroscopy（EIS） and differential capacity curves（dQ/dE）.Finger print XRD patterns of LiMnOand LiNiAlMnOfortify the high degree of crystallinity with better phase purity.FESEM images of the undoped pristine spinel illustrate uniform spherical grains surface morphology with an average particle size of 0.5 μm while Ni doped particles depict the spherical grains growth（50nm） with ice-cube surface morphology.TEM images of the spinel LiMnOshows the uniform spherical morphology with particle size of（100 nm） while low level of Al-doping spinel（LiNio.5Alo.05Mn1.45O4） displaying cloudy particles with agglomerated particles of（50nm）.The LiMnOsamples calcined at 850℃ deliver the discharge capacity of 130 mAh/g in the first cycle corresponds to 94%coiumbic efficiency with capacity fade of 1.5 mAh/g/cycle over the investigated 10 cycles.Among all four dopant compositions investigated,LiNiAlMnOdelivers the maximum discharge capacity of 126 mAh/g during the first cycle and shows the stable cycling performance with low capacity fade of 1 mAh/g/cycle（capacity retention of 92%） over the investigated 10 cycles.Electrochemical impedance studies of spinel LiMnOand LiNiAlMnOdepict the high and low real polarization of 1562 and 1100 Ω.展开更多
Attempts for higher output power and thermal efficiency of gas turbines make the inlet temperature of turbine to be far beyond the material melting temperature.Therefore,to protect the airfoil in gas turbine from hot ...Attempts for higher output power and thermal efficiency of gas turbines make the inlet temperature of turbine to be far beyond the material melting temperature.Therefore,to protect the airfoil in gas turbine from hot gas and eventually prolong the lifetime of the blade,internal and film cooling structures with better thermal performance and cooling effectiveness are urgently needed.However,the traditional way of proceeding involves numerous simulations,additional experiments,and separate trials.Optimization of turbine cooling structures is an effective way to achieve better structures with higher overall performances while considering the multiple objectives,disciplines or subsystems.In this context,this paper reviews optimization research works on film cooling structures and internal cooling structures in gas turbines by means of various optimization methods.This review covers the following aspects:(A)optimization of film cooling conducted on flat plates and on turbine blades or vanes;(B)optimization of jet impingement cooling structures;(C)optimization of rib shapes,dimple shapes,pin–fin arrays in the cooling channels;(D)optimization of U-bend shaped cooling channels,and internal cooling systems of turbine blades or vanes.The review shows that through a reliable and accurate optimization procedure combined with conjugate heat transfer analysis,higher overall thermal performance can be acquired for single-objective or multi-objectives balanced by other constrained conditions.Future ways forward are pointed out in this review.展开更多
The present study involves the fabrication of tungsten trioxide(WO3) nanofibers by an electrospinning technique using polyvinyl pyrrolidone(PVP)/citric acid/tungstic acid as precursor solution. It was found that the P...The present study involves the fabrication of tungsten trioxide(WO3) nanofibers by an electrospinning technique using polyvinyl pyrrolidone(PVP)/citric acid/tungstic acid as precursor solution. It was found that the PVP concentration was one of the most crucial processing parameters determining the final properties of WO3 nanofibers. The optimum concentration of PVP was from 75 to 94 g L-1. The average diameter of the nanofibers increases with increasing the PVP concentration, whereas it is decreased after sintering and orthorhombic structure were formed at 500 °C. The photocatalytic properties of the as-synthesized nanofibers were also investigated by degrading methylene blue and twofold efficiency was obtained compared with that of commercial WO3 microparticles.展开更多
The design of cost-effective, highly active catalysts for hydrogen energy production is a vital element in the societal pursuit of sustainable energy. Water electrolysis is one of the most convenient processes to prod...The design of cost-effective, highly active catalysts for hydrogen energy production is a vital element in the societal pursuit of sustainable energy. Water electrolysis is one of the most convenient processes to produce high purity hydrogen. Cobalt-based catalysts are well-known electrocatalysts for oxygen evolution reaction（OER）. In this article, all these merits indicate that the present cobalt nanocomposite is a promising electrocatalyst for OER. C–CoO-nanorods catalyst with nanorod structure was synthesized by hydrothermal treatment of CoCl·6HO/dextrose/urea mixture at 180 °C for 18 h and then calcined at400 °C for 3.5 h. The role of dextrose percentage in solution to achieve the uniform coating of carbon on the surface of CoO-nanorods has been demonstrated. The prepared materials were characterized by X-ray diffraction（XRD）, X-ray photoelectron spectrum（XPS）, field emission scanning electron microscopy（FE-SEM）, high-resolution transmission electron microscopy（HR-TEM）, and Brunauer–Emmett–Teller instrument（BET）. Due to its unique morphology, the C–CoO-nanorods catalyst exhibited better activity than CoO-microplates catalyst for OER in 1 M KOH aqueous solution. The results showed a highly efficient, scalable, and low-cost method for developing highly active and stable OER electrocatalysts in alkaline solution.展开更多
A rolling with cone-shaped roll, the diameter of which continuously varies along the axial direction, has been proposed as a new shear rolling for controlling the texture of an aluminum alloy sheet. In this study, var...A rolling with cone-shaped roll, the diameter of which continuously varies along the axial direction, has been proposed as a new shear rolling for controlling the texture of an aluminum alloy sheet. In this study, variations in the texture and Lankford value of a 1070 aluminum sheet rolled by the cone-shaped roll were investigated. Rolling with the cone-shaped roll was found to impose intense shear strain at the edges of the specimen, specifically near the surface. The shear directions in the left and right portions of the specimen were opposite to each other. The surface and middle layer of the specimen rolled by the cone-shaped roll and the reference specimen were characterized by a shear texture and typical recrystallization texture components, respectively. Notably, the specimen rolled by the cone-shaped roll exhibited smaller texture intensity than the reference specimen, especially at the surface, and the shear texture-components were observed at relatively deeper positions. As a result of Lankford value measurements, the specimen rolled with the cone-shape roll exhibited a smaller planar anisotropy than the reference specimen and an average Lankford value close to unity, which are likely due to the texture modifications introduced during rolling with the cone-shaped roll.展开更多
基金supported by the introduction of Talent Research Fund in Nanjing Institute of Technology(YKJ202204)the National Natural Science Foundation of China(52401282 and 52300206)the Natural Science Foundation of Jiangsu Province(BK20230701 and BK20230705).
文摘Achieving high-energy density remains a key objective for advanced energy storage systems.However,challenges,such as poor cathode conductivity,anode dendrite formation,polysulfide shuttling,and electrolyte degradation,continue to limit performance and stability.Molecular and ionic dipole interactions have emerged as an effective strategy to address these issues by regulating ionic transport,modulating solvation structures,optimizing interfacial chemistry,and enhancing charge transfer kinetics.These interactions also stabilize electrode interfaces,suppress side reactions,and mitigate anode corrosion,collectively improving the durability of high-energy batteries.A deeper understanding of these mechanisms is essential to guide the design of next-generation battery materials.Herein,this review summarizes the development,classification,and advantages of dipole interactions in high-energy batteries.The roles of dipoles,including facilitating ion transport,controlling solvation dynamics,stabilizing the electric double layer,optimizing solid electrolyte interphase and cathode–electrolyte interface layers,and inhibiting parasitic reactions—are comprehensively discussed.Finally,perspectives on future research directions are proposed to advance dipole-enabled strategies for high-performance energy storage.This review aims to provide insights into the rational design of dipole-interactive systems and promote the progress of electrochemical energy storage technologies.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2022R1F1A1070168,2020R1C1C1004322)the Korea Institute of Industrial Technology as Development of core technology for smart wellness care based on cleaner production process technology(KITECH-PEH23030)+1 种基金supported by the Renewable Surplus Sector Coupling Technology Program of the Korea Institute of Energy Technology Evaluation and Planning(KETEP)granted financial resource from the Ministry of Trade,Industry&Energy,Republic of Korea(No.20226210100050)the National Research Council of Science&Technology(NST)grant by the Korea government(MSIT)(No.CPS21141-100)。
文摘Thick electrodes can substantially enhance the overall energy density of batteries.However,insufficient wettability of aqueous electrolytes toward electrodes with conventional hydrophobic binders severely limits utilization of active materials with increasing the thickness of electrodes for aqueous batteries,resulting in battery performance deterioration with a reduced capacity.Here,we demonstrate that controlling the hydrophilicity of the thicker electrodes is critical to enhancing the overall energy density of batteries.Hydrophilic binders are synthesized via a simple sulfonation process of conventional polyvinylidene fluoride binders,considering physicochemical properties such as mechanical properties and adhesion.The introduction of abundant sulfonate groups of binders(i)allows fast and sufficient electrolyte wetting,and(ii)improves ionic conduction in thick electrodes,enabling a significant increase in reversible capacities under various current densities.Further,the sulfonated binder effectively inhibits the dissolution of cathode materials in reactive aqueous electrolytes.Overall,our findings significantly enhance the energy density and contribute to the development of practical zinc-ion batteries.
文摘This study described a hydrometallurgical method to investigate the separation of rare earth elements（REEs）from rare earth polishing powder wastes（REPPWs）containing large amounts of rare earth oxides with a major phase of CeO2 and minor phases of La2O3,Pr2O3,and Nd2O3 using a process devised by the authors.The suggested approach consisted of five processes：the synthesis of NaR E（SO4）2·xH2O from rare earth oxides in Na2SO4-H2SO4-H2 O solutions（Process 1）,the conversion of NaR E（SO4）2·xH2O into RE（OH）3 using NaO H（Process 2）,and the oxidation of Ce（OH）3 into Ce（OH）4 using air with O2 injection（Process 3）,followed by Processes 4 and 5 for separation of REEs by acid leaching using HCl and H2SO4,respectively.To confirm the high yield of NaR E（SO4）2·xH2O in Process 1,experiments were carried out under various Na2SO4 concentrations（0.4–2.5 mol/L）,sulfuric acid concentrations（6–14 mol/L）,and reaction temperatures（95–125 oC）.In addition,the effect of the pH value on the separation of Ce（OH）4 in HCl-H2 O solutions with Ce（OH）4,La-,Pr-,and Nd（OH）3 in Process 4 was also investigated.On the basis of above results,the possibility of effective separation of REEs from REPPWs could be confirmed.
文摘1. Foreword Energy storage plays a key role in the transition towards a carbon-neutral economy. By balancing power grids and saving surplus energy, it represents a concrete means of improving energy efficiency and integrating more renewable energy sources into electricity systems. A variety of technologies to store energy are developing at a fast pace and increasingly becomingmoremarketcompetitive,includingtraditional electric energy storage, thermal energy storage, and newly developed hydrogen energy storage, etc. The demand for energy storage system with high power and efficiency boosts the development in the advanced techniques and materials,such as batteries, super-capacitors, molten salts, and catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER).
基金supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (2021R1A2C1014280)supported by the “Regional Innovation Strategy (RIS)” through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (MOE) (2021RIS-004)+1 种基金the Fundamental Research Program of the Korea Institute of Material Science (KIMS) (PNK9370)the calculation resources were supported by the Supercomputing Center in Korea Institute of Science and Technology Information (KISTI) (KSC-2022-CRE-0030)。
文摘The anionic redox has been widely studied in layered-oxide-cathodes in attempts to achieve highenergy-density for Na-ion batteries(NIBs).It is known that an oxidation state of Mn^(4+) or Ru^(5+) is essential for the anionic reaction of O^(2-)/O~-to occur during Na^(+) de/intercalation.However,here,we report that the anionic redox can occur in Ru-based layered-oxide-cathodes before full oxidation of Ru^(4+)/Ru^(5+).Combining studies using first-principles calculation and experimental techniques reveals that further Na^(+) deintercalation from P2-Na_(0.33)[Mg_(0.33)Ru_(0.67)]O_(2) is based on anionic oxidation after 0.33 mol Na^(+) deintercalation from P2-Na_(0.67)[Mg_(0.33)Ru_(0.67)]O_(2) with cationic oxidation of Ru^(4+)/Ru^(4.5+).Especially,it is revealed that the only oxygen neighboring 2Mg/1 Ru can participate in the anionic redox during Na^(+) de/intercalation,which implies that the Na-O-Mg arrangement in the P2-Na_(0.33)[M9_(0.33)Ru_(0.67)]O_(2) structure can dramatically lower the thermodynamic stability of the anionic redox than that of cationic redox.Through the O anionic and Ru cationic reaction,P2-Na_(0.67)[Mg_(0.33)Ru_(0.67)]O_(2) exhibits not only a large specific capacity of~172 mA h g^(-1) but also excellent power-capability via facile Na^(+) diffusion and reversible structural change during charge/discharge.These findings suggest a novel strategy that can increase the activity of anionic redox by modulating the local environment around oxygen to develop high-energy-density cathode materials for NIBs.
文摘As part of the national strategy to further develop the wind energy sector,the eight prefectures of Upper Guinea have been selected.Using meteorological data recorded over thirty years(1991-2021)at a height of 20 m,we assessed wind resources in terms of characteristic speeds,power and available energy.To this end,the Weibull distribution method was used and the following values were obtained:3.66 m/s for the average speed;1,102.83 W/m^(2)for the available power and 8,747.06 kWh/m^(2)/year for the annual available energy.
基金supported by the Nano&Material Technology Development Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(RS-2024-00436563)supported by Brain Pool program funded by the Ministry of Science and ICT through the National Research Foundation of Korea(Grant No.RS-2023-00284361).
文摘Seawater is the most abundant source of molecular hydrogen.Utilizing the hydrogen reserves present in the seawater may inaugurate innovative strategies aimed at advancing sustainable energy and environmental preservation endeavors in the future.Recently,there has been a surge in study in the field addressing the production of hydrogen through the electrochemical seawater splitting.However,the performance and durability of the electrode have limitations due to the fact that there are a few challenges that need to be addressed in order to make the technology suitable for the industrial purpose.The active site blockage caused by chloride ions that are prevalent in seawater and chloride corrosion is the most significant issue;it has a negative impact on both the activity and the durability of the anode component.Addressing this particular issue is of upmost importance in the seawater splitting area.This review concentrates on the newly developed materials and techniques for inhibiting chloride ions by blocking the active sites,simultaneously preventing the chloride corrosion.It is anticipated that the concept will be advantageous for a large audience and will inspire researchers to study on this particular area of concern.
基金the technical support for Nano-X from Suzhou Institute of Nano-Tech and NanoBionics,Chinese Academy of Sciences(SINANO)supported by the National Key R&D Program of China(2021YFB3800300)+2 种基金the National Natural Science Foundation of China(22179059,22239002,92372201)the science and technology innovation fund for emission peak and carbon neutrality of Jiangsu province(BK20231512,BK20220034)the Key R&D project funded by department of science and technology of Jiangsu Province(BE2020003)。
文摘Aluminum(Al)exhibits excellent electrical conductivity,mechanical ductility,and good chemical compatibility with high-ionic-conductivity electrolytes.This makes it more suitable as an anode material for all-solid-state lithium batteries(ASSLBs)compared to the overly reactive metallic lithium anode and the mechanically weak silicon anode.This study finds that the pre-lithiated Al anode demonstrates outstanding interfacial stability with the Li_6PS_5Cl(LPSCl)electrolyte,maintaining stable cycling for over 1200 h under conditions of deep charge-discharge.This paper combines the pre-lithiated Al anode with a high-nickel cathode,LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2),paired with the highly ionic conductive LPSCl electrolyte,to design an ASSLB with high energy density and stability.Using anode pre-lithiation techniques,along with dual-reinforcement technology between the electrolyte and the cathode active material,the ASSLB achieves stable cycling for 1000 cycles at a 0.2C rate,with a capacity retention rate of up to 82.2%.At a critical negative-to-positive ratio of 1.1,the battery's specific energy reaches up to 375 Wh kg^(-1),and it maintains over 85.9%of its capacity after 100 charge-discharge cycles.This work provides a new approach and an excellent solution for developing low-cost,high-stability all-solid-state batteries.
基金supported by the Global Joint Research Program funded by the Pukyong National University(202411790001)the Nano&Material Technology Development Program through the National Research Foundation of Korea(NRF)+2 种基金funded by the Ministry of Science and ICT(RS-2024-00446825)the Technology Innovation Program(RS-2024-00418815)funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea)。
文摘Rechargeable magnesium batteries are promising alternatives to traditional lithium batteries because of the high abundance of Mg compounds in earth crust,their low toxicity,and possible favorable properties as electrodes'material.However,Mg metal anodes face several challenges,notably the natively existence of an inactive oxide layer on their surfaces,which reduces their effectiveness.Additionally,interactions of Mg electrodes with electrolyte solutions'components can lead to the formation of insulating surface layers,that can fully block them for ions transport.This review addresses these issues by focusing on surface treatments strategies to enhance electrochemical performance of Mg anodes.It highlights chemical and physical modification techniques to prevent oxidation and inactive-layers formation,as well as their practical implications for MIBs.We also examined the impact of Mg anodes'surface engineering on their electrochemical reversibility and cycling efficiency.Finally,future research directions to improve the performance and commercial viability of magnesium anodes and advance development of high-capacity,safe,and cost-effective energy storage systems based on magnesium electrochemistry are discussed.
基金supported by the Technology Innovation Program(No.20011712)funded by the Ministry of Trade,Industry,and Energy(MOTIE,Korea)a National Research Foundation of Korea(NRF)grant funded by the Ministry of Science and ICT(MSIT)(No.2022M3J1A108538),Korea+2 种基金the support of the Nano&Material Technology Development Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(RS-2024-00444986,50%)the Institute for Basic Science(IBS-R036-D1)。
文摘Understanding the degradation phenomenon of proton exchange membrane fuel cells under electrochemical cycling requires an analysis of the porous carbon support structure.Key factors contributing to this phenomenon include changes in the total porosity and viable surface area for electrochemical reactions.Electron tomography-based serial section imaging using focused ion beam-scanning electron microscopy(FIB-SEM)can elucidate this phenomenon at a nanoscale resolution.However,this highresolution tomographic analysis requires a huge image dataset and manual inputs in rule-based workflows;these requirements are time-consuming and often cause experimental difficulties and unreliable interpretations.We propose a deep learning-empowered approach comprising a two-step automated process for image interpolation and semantic segmentation to address the practical issues encountered in FIB-SEM electron tomography.An optimally trained interpolation model can reduce the image data requirement by more than 95%to analyze the structural degradation of carbon supports after electrochemical cycling while maintaining the reliability obtained in conventional tomographic analysis with several hundred images.Because the subsequent image segmentation model excludes a complicated manual filtering process,the relevant structural parameters can be reliably measured without human bias.Our sparse-section imaging-based deep learning process can allow cost-efficient analysis and reliable measurement of the degree of cycling-induced carbon corrosion.
基金financially supported by the Institute of Civil Military Technology Cooperation funded by the Defense Acquisition Program Administration and Ministry of Trade,Industry and Energy of Korean government under grant No.22-CM-FC-20the support from the DGIST Supercomputing and Bigdata Center。
文摘With electric vehicles(EVs)emerging as a primary mode of transportation,ensuring their reliable operation in harsh environments is crucial.However,lithium-ion batteries(LIBs)suffer from severe polarization at low temperatures,limiting their operation in cold climates.In addition,difficulties in discovering new battery materials have highlighted a growing demand for innovative electrode designs that achieve high performance,even at low temperatu res.To address this issue,we prepared a thin,resistive,and patterned carbon interlayer on the anode current collector.This carbon-patterned layer(CPL)serves as a self-heating layer to efficiently elevate the entire cell temperature,thus improving the rate capability and cyclability at low temperatures while maintaining the performance at room temperature.Furthermore,we validated the versatile applicability of CPLs to large-format LIB cells through experimental studies and electrochemo-thermal multiphysics modeling and simulations,with the results confirming 11%capacity enhancement in 21,700 cylindrical cells at a 0.5C-rate and-24℃.We expect this electrode design to offer reliable power delivery in harsh climates,thereby potentially expanding the applications of LIBs.
基金financially supported by the National Natural Science Foundation of China(52102206)the Natural Science Foundation of Beijing Municipality-Shunyi Innovation Collaborative Joint Fund(L247018)+2 种基金the Natural Science Foundation of Beijing Municipality(2254076 and 2252024)the Central Guidance on Local Science and Technology Development Fund of Hebei Province(246Z4412G)the Fundamental Research Funds for the Central Universities(2025MS022,North China Electric Power University)。
文摘Composite cathodes integrating Ni-rich layered oxides and oxide solid electrolytes are essential for highenergy all-solid-state lithium-ion batteries(ASSLBs),yet interfacial degradation during high-temperature co-sintering(>600℃)remains a critical challenge.While surface passivation strategies mitigate reactions below 400℃,their effectiveness diminishes at elevated temperatures due to inability to counteract Li^(+)concentration gradients.Here,we introduce in situ lithium compensators,i.e.,LiOH/Li_(2)CO_(3),into NCM-LATP composite cathodes to dynamically replenish Li^(+)during co-sintering.These additives melt to form transient Li^(+)-rich phases that back-diffuse Li^(+)into NCM lattices,suppressing layered-to-rock salt transitions and stabilizing the interface.Quasi in situ XRD confirms retention of the layered structure at temperature up to 700℃,while electrochemical tests demonstrate a reversible capacity of 222.2 mA h g^(-1)—comparable to NCM before co-sintering—and an impressive 65.3% capacity retention improvement over100 cycles.In contrast,uncompensated cathodes exhibit severe degradation to 96.5 mA h g^(-1)due to Li depletion and resistive Li-Ti-O interphases.This strategy integrates sacrificial chemistry with scalable powder-mixing workflows,achieving a 93.4% reduction in interfacial impedance.By addressing Li^(+)flux homogenization and structural stability,this work provides a practical pathway toward industrialscale fabrication of high-performance ASSLBs.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.NRF-2021M3H4A1A02048529)the Ministry of Trade,Industry and Energy(MOTIE)of the Korean government under grant No.RS-2022-00155854support from the DGIST Supercomputing and Big Data Center.
文摘To enhance the electrochemical performance of lithium-ion battery anodes with higher silicon content,it is essential to engineer their microstructure for better lithium-ion transport and mitigated volume change as well.Herein,we suggest an effective approach to control the micropore structure of silicon oxide(SiO_(x))/artificial graphite(AG)composite electrodes using a perforated current collector.The electrode features a unique pore structure,where alternating high-porosity domains and low-porosity domains markedly reduce overall electrode resistance,leading to a 20%improvement in rate capability at a 5C-rate discharge condition.Using microstructure-resolved modeling and simulations,we demonstrate that the patterned micropore structure enhances lithium-ion transport,mitigating the electrolyte concentration gradient of lithium-ion.Additionally,perforating current collector with a chemical etching process increases the number of hydrogen bonding sites and enlarges the interface with the SiO_(x)/AG composite electrode,significantly improving adhesion strength.This,in turn,suppresses mechanical degradation and leads to a 50%higher capacity retention.Thus,regularly arranged micropore structure enabled by the perforated current collector successfully improves both rate capability and cycle life in SiO_(x)/AG composite electrodes,providing valuable insights into electrode engineering.
基金supported by the Natural Science Foundation of China(Nos.52125202,52202100,and U24A2065)the Natural Science Foundation of Jiangsu Province(BK20243016)Fundamental Research Funds for the Central Universities,China Postdoctoral Science Foundation(No.2024T171166).
文摘Aqueous zinc-ion batteries(AZIBs)have garnered considerable attention as promising post-lithium energy storage technologies owing to their intrinsic safety,cost-effectiveness,and competitive gravimetric energy density.However,their practical commercialization is hindered by critical challenges on the anode side,including dendrite growth and parasitic reactions at the anode/electrolyte interface.Recent studies highlight that rational electrolyte structure engineering offers an effective route to mitigate these issues and strengthen the electrochemical performance of the zinc metal anode.In this review,we systematically summarize state-of-the-art strategies for electrolyte optimization,with a particular focus on the zinc salts regulation,electrolyte additives,and the construction of novel electrolytes,while elucidating the underlying design principles.We further discuss the key structure–property relationships governing electrolyte behavior to provide guidance for the development of next-generation electrolytes.Finally,future perspectives on advanced electrolyte design are proposed.This review aims to serve as a comprehensive reference for researchers exploring high-performance electrolyte engineering in AZIBs.
基金sponsored by the National Natural Science Foundation of China(Nos.51676163,51976161,U1867218)the National 111 Project,China(No.B18041)+1 种基金the Fundamental Research Funds of Shenzhen City,China(No.JCYJ20170306155153048)the Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University,China(No.CX202029).
文摘Supercritical fluids(e.g.,hydrocarbon fuels,water,carbon dioxide,and organic working medium,etc)have been recognized as working media to improve thermal efficiencies in power cycles and energy conversion,and have been used or selected as the working fluids in engineering fields such as aerospace,nuclear power,solar energy,refrigeration,geothermal energy,chemical technology,and so on.To better understand the interesting characteristic or abnormal behaviors of supercritical fluids,most valuable research works(including experimental results and numerical studies)from domestic and abroad have been documented.As such,this paper presents a comprehensive review on heat transfer behaviors of some supercritical fluids in engineering applications.This review focuses on recently available articles published mainly from 2016 up to the present time.The common problems(i.e.,heat transfer enhancement and heat transfer deterioration particularly for the supercritical hydrocarbon fuels)in the supercritical field are summarized and some perspectives on future prospects are also included.
基金support given under the "Brain Pool Program of the Korean Federation of Science and Technology Societies" (KOFST), Republic of South Koreasupported by the Human Resources Development Program (No. 20124010203270) of the Korea Institute of Energy Technology EvaluationPlanning (KETEP) grant funded by the Korea Government Ministry of Trade, Industry and Energy
文摘LiMnOand LiNiAlyMnO（x= 0.50;y = 0.05-0.50） powders have been synthesized via facile solgel method using Behenic acid as active cheiating agent.The synthesized samples are subjected to physical characterizations such as thermo gravimetric analysis（TG/DTA）,X-ray diffraction（XRD）,Fourier transform infrared spectroscopy（FT-IR）,field-emission scanning electron microscopy（FESEM）,transmission electron microscopy（TEM） and electrochemical studies viz.,galvanostatic cycling properties,electrochemical impedance spectroscopy（EIS） and differential capacity curves（dQ/dE）.Finger print XRD patterns of LiMnOand LiNiAlMnOfortify the high degree of crystallinity with better phase purity.FESEM images of the undoped pristine spinel illustrate uniform spherical grains surface morphology with an average particle size of 0.5 μm while Ni doped particles depict the spherical grains growth（50nm） with ice-cube surface morphology.TEM images of the spinel LiMnOshows the uniform spherical morphology with particle size of（100 nm） while low level of Al-doping spinel（LiNio.5Alo.05Mn1.45O4） displaying cloudy particles with agglomerated particles of（50nm）.The LiMnOsamples calcined at 850℃ deliver the discharge capacity of 130 mAh/g in the first cycle corresponds to 94%coiumbic efficiency with capacity fade of 1.5 mAh/g/cycle over the investigated 10 cycles.Among all four dopant compositions investigated,LiNiAlMnOdelivers the maximum discharge capacity of 126 mAh/g during the first cycle and shows the stable cycling performance with low capacity fade of 1 mAh/g/cycle（capacity retention of 92%） over the investigated 10 cycles.Electrochemical impedance studies of spinel LiMnOand LiNiAlMnOdepict the high and low real polarization of 1562 and 1100 Ω.
基金supported by the National Natural Science Foundation of China (No. 51676163)the National 111 Project, China (No. B18041the Guangdong Basic and Applied Basic Research Foundation, China (No. 2019A1515111146)
文摘Attempts for higher output power and thermal efficiency of gas turbines make the inlet temperature of turbine to be far beyond the material melting temperature.Therefore,to protect the airfoil in gas turbine from hot gas and eventually prolong the lifetime of the blade,internal and film cooling structures with better thermal performance and cooling effectiveness are urgently needed.However,the traditional way of proceeding involves numerous simulations,additional experiments,and separate trials.Optimization of turbine cooling structures is an effective way to achieve better structures with higher overall performances while considering the multiple objectives,disciplines or subsystems.In this context,this paper reviews optimization research works on film cooling structures and internal cooling structures in gas turbines by means of various optimization methods.This review covers the following aspects:(A)optimization of film cooling conducted on flat plates and on turbine blades or vanes;(B)optimization of jet impingement cooling structures;(C)optimization of rib shapes,dimple shapes,pin–fin arrays in the cooling channels;(D)optimization of U-bend shaped cooling channels,and internal cooling systems of turbine blades or vanes.The review shows that through a reliable and accurate optimization procedure combined with conjugate heat transfer analysis,higher overall thermal performance can be acquired for single-objective or multi-objectives balanced by other constrained conditions.Future ways forward are pointed out in this review.
基金supported by the National Research Foundation of Korea(NRF)-Grants funded by the Ministry of ScienceICT and Future Planning(2014R1A2A2A01004352)the Ministry of Education(2009-0093816),Republic of Korea
文摘The present study involves the fabrication of tungsten trioxide(WO3) nanofibers by an electrospinning technique using polyvinyl pyrrolidone(PVP)/citric acid/tungstic acid as precursor solution. It was found that the PVP concentration was one of the most crucial processing parameters determining the final properties of WO3 nanofibers. The optimum concentration of PVP was from 75 to 94 g L-1. The average diameter of the nanofibers increases with increasing the PVP concentration, whereas it is decreased after sintering and orthorhombic structure were formed at 500 °C. The photocatalytic properties of the as-synthesized nanofibers were also investigated by degrading methylene blue and twofold efficiency was obtained compared with that of commercial WO3 microparticles.
基金supported by the National Research Foundation of Korea(NRF)–Grants funded by the Ministry of Science,ICT and Future Planning(2014R1A2A2A01004352),Republic of Korea
文摘The design of cost-effective, highly active catalysts for hydrogen energy production is a vital element in the societal pursuit of sustainable energy. Water electrolysis is one of the most convenient processes to produce high purity hydrogen. Cobalt-based catalysts are well-known electrocatalysts for oxygen evolution reaction（OER）. In this article, all these merits indicate that the present cobalt nanocomposite is a promising electrocatalyst for OER. C–CoO-nanorods catalyst with nanorod structure was synthesized by hydrothermal treatment of CoCl·6HO/dextrose/urea mixture at 180 °C for 18 h and then calcined at400 °C for 3.5 h. The role of dextrose percentage in solution to achieve the uniform coating of carbon on the surface of CoO-nanorods has been demonstrated. The prepared materials were characterized by X-ray diffraction（XRD）, X-ray photoelectron spectrum（XPS）, field emission scanning electron microscopy（FE-SEM）, high-resolution transmission electron microscopy（HR-TEM）, and Brunauer–Emmett–Teller instrument（BET）. Due to its unique morphology, the C–CoO-nanorods catalyst exhibited better activity than CoO-microplates catalyst for OER in 1 M KOH aqueous solution. The results showed a highly efficient, scalable, and low-cost method for developing highly active and stable OER electrocatalysts in alkaline solution.
基金Japan Aluminum Association for the financial aid extended to this study
文摘A rolling with cone-shaped roll, the diameter of which continuously varies along the axial direction, has been proposed as a new shear rolling for controlling the texture of an aluminum alloy sheet. In this study, variations in the texture and Lankford value of a 1070 aluminum sheet rolled by the cone-shaped roll were investigated. Rolling with the cone-shaped roll was found to impose intense shear strain at the edges of the specimen, specifically near the surface. The shear directions in the left and right portions of the specimen were opposite to each other. The surface and middle layer of the specimen rolled by the cone-shaped roll and the reference specimen were characterized by a shear texture and typical recrystallization texture components, respectively. Notably, the specimen rolled by the cone-shaped roll exhibited smaller texture intensity than the reference specimen, especially at the surface, and the shear texture-components were observed at relatively deeper positions. As a result of Lankford value measurements, the specimen rolled with the cone-shape roll exhibited a smaller planar anisotropy than the reference specimen and an average Lankford value close to unity, which are likely due to the texture modifications introduced during rolling with the cone-shaped roll.
