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Nanostructuring of Mg-Based Hydrogen Storage Materials:Recent Advances for Promoting Key Applications 被引量:7
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作者 Li Ren Yinghui Li +6 位作者 Ning Zhang Zi Li Xi Lin Wen Zhu Chong Lu Wenjiang Ding Jianxin Zou 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第7期30-56,共27页
With the depletion of fossil fuels and global warming,there is an urgent demand to seek green,low-cost,and high-efficiency energy resources.Hydrogen has been considered as a potential candidate to replace fossil fuels... With the depletion of fossil fuels and global warming,there is an urgent demand to seek green,low-cost,and high-efficiency energy resources.Hydrogen has been considered as a potential candidate to replace fossil fuels,due to its high gravimetric energy density(142 MJ kg^(-1)),high abundance(H_(2)O),and environmentalfriendliness.However,due to its low volume density,effective and safe hydrogen storage techniques are now becoming the bottleneck for the"hydrogen economy".Under such a circumstance,Mg-based hydrogen storage materials garnered tremendous interests due to their high hydrogen storage capacity(~7.6 wt%for MgH_(2)),low cost,and excellent reversibility.However,the high thermodynamic stability(ΔH=-74.7 kJ mol^(-1)H_(2))and sluggish kinetics result in a relatively high desorption temperature(>300℃),which severely restricts widespread applications of MgH_(2).Nano-structuring has been proven to be an effective strategy that can simultaneously enhance the ab/de-sorption thermodynamic and kinetic properties of MgH_(2),possibly meeting the demand for rapid hydrogen desorption,economic viability,and effective thermal management in practical applications.Herein,the fundamental theories,recent advances,and practical applications of the nanostructured Mg-based hydrogen storage materials are discussed.The synthetic strategies are classified into four categories:free-standing nano-sized Mg/MgH_(2)through electrochemical/vapor-transport/ultrasonic methods,nanostructured Mg-based composites via mechanical milling methods,construction of core-shell nano-structured Mg-based composites by chemical reduction approaches,and multi-dimensional nano-sized Mg-based heterostructure by nanoconfinement strategy.Through applying these strategies,near room temperature ab/de-sorption(<100℃)with considerable high capacity(>6 wt%)has been achieved in nano Mg/MgH_(2)systems.Some perspectives on the future research and development of nanostructured hydrogen storage materials are also provided. 展开更多
关键词 Mg-based hydrogen storage materials NANOSTRUCTURE Hydrogen storage THERMODYNAMICS KINETICS On-board hydrogen storage
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Efficient Nanostructuring of Isotropic Gas-Atomized MnAl Powder by Rapid Milling(30s) 被引量:1
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作者 J.Rial E.M.Palmero A.Bollero 《Engineering》 SCIE EI 2020年第2期173-177,共5页
An unprecedentedly short milling time of 30 s was applied to gas-atomized MnAl powder in order to develop permanent magnet properties and,in particular,coercivity.It is shown that such a short processing time followed... An unprecedentedly short milling time of 30 s was applied to gas-atomized MnAl powder in order to develop permanent magnet properties and,in particular,coercivity.It is shown that such a short processing time followed by annealing results in efficient nanostructuring and controlled phase transformation.The defects resulting from the microstrain induced during milling,together with the creation of the bphase during post-annealing,act as pinning centers resulting in an enhanced coercivity.This study shows the importance of finding a balance between the formation of the ferromagnetic s-MnAl phase and the bphase in order to establish a compromise between magnetization and coercivity.A coercivity as high as 4.2 kOe(1 Oe=79.6 A·m^-1)was obtained after milling(30 s)and annealing,which is comparable to values previously reported in the literature for milling times exceeding 20 h.This reduction of the postannealing temperature by 75℃ for the as-milled powder and a 2.5-fold increase in coercivity,while maintaining practically unchanged the remanence of the annealed gas-atomized material,opens a new path for the synthesis of isotropic MnAl-based powder. 展开更多
关键词 Permanent magnets(PMs) nanostructuring Phase transformation MnAl Gas ATOMIZATION Ball MILLING
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Optical near-field imaging and nanostructuring by means of laser ablation 被引量:6
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作者 Johannes Boneberg Paul Leiderer 《Opto-Electronic Science》 2022年第1期2-25,共24页
In this review we consider the development of optical near-field imaging and nanostructuring by means of laser ablation since its early stages around the turn of the century.The interaction of short,intense laser puls... In this review we consider the development of optical near-field imaging and nanostructuring by means of laser ablation since its early stages around the turn of the century.The interaction of short,intense laser pulses with nanoparticles on a surface leads to laterally tightly confined,strongly enhanced electromagnetic fields below and around the nano-objects,which can easily give rise to nanoablation.This effect can be exploited for structuring substrate surfaces on a length scale well below the diffraction limit,one to two orders smaller than the incident laser wavelength.We report on structure formation by the optical near field of both dielectric and metallic nano-objects,the latter allowing even stronger and more localized enhancement of the electromagnetic field due to the excitation of plasmon modes.Structuring with this method enables one to nanopattern large areas in a one-step parallel process with just one laser pulse irradiation,and in the course of time various improvements have been added to this technique,so that also more complex and even arbitrary structures can be produced by means of nanoablation.The near-field patterns generated on the surface can be read out with high resolution techniques like scanning electron microscopy and atomic force microscopy and provide thus a valuable tool-in conjunction with numerical calculations like finite difference time domain(FDTD)simulations-for a deeper understanding of the optical and plasmonic properties of nanostructures and their applications. 展开更多
关键词 nanostructuring optical near field laser ablation PLASMONICS
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Nanostructuring and Thermoelectric Properties of Bulk N-type Mg_2Si
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作者 杨梅君 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第6期912-916,共5页
Preparation and thermoelectric properties of nanostructured n-type Mg2Si bulk materials were reported. Nanosized Mg2Si powder was obtained by mechanical milling of the microsized Mg2Si powder prepared by solid-state r... Preparation and thermoelectric properties of nanostructured n-type Mg2Si bulk materials were reported. Nanosized Mg2Si powder was obtained by mechanical milling of the microsized Mg2Si powder prepared by solid-state reaction. The bulk materials with 30 nm and 5 μm were prepared by spark plasma sintering of the nanosized and microsized Mg2Si powder, respectively. Both the samples show n-type conduction and the Seebeck coefficient of the sintered samples increase determinately with the grain size decrease from 5 μm to 30 nm. On the other hand, the electrical and thermal conductivity decrease with the decrease of grain size. Accordingly, decreasing their grain size increases their thermoelectric-figure-of-merit. A maximum thermoelectric figure of merit of 0.36 has been obtained for the nanostuctured Mg2Si sample at 823 K, which is 38% higher than that of microsized Mg2Si bulk materials and higher than results of other literatures. It could be expected that the properties of the nanocomposites could be further improved by doping optimization. 展开更多
关键词 semiconductor thermoelectric effects MG2SI nanostructuring
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Self-Organizing Processes in Semiconductor Materials Science on the Example of Nanostructuring of por-Si
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作者 Kurbangali B. Tynyshtykbaev Talant Aitmukan +3 位作者 Ainur T. Issova Bagdat A. Rakhymetov Mukhtar A. Yeleuov Serekbol Zh. Tokmoldin 《Materials Sciences and Applications》 2013年第8期1-11,共11页
Self-organization processes in semiconductor materials on the example of nanostructuring of por-Si at long anodic etching of p-type Si in the electrolyte with internal source of the current are shown. In conditions of... Self-organization processes in semiconductor materials on the example of nanostructuring of por-Si at long anodic etching of p-type Si in the electrolyte with internal source of the current are shown. In conditions of a “soft” etching of the Si point defects are formed and in the subsequently occurs their spatial-temporal ordering. This leads to the ordering pores and the nanostructuring of por-Si. Self-organization mechanism of Si nanocrystallites islets is described by the effects of the elastically-deformative, defectively-deformative and capillary-fluctuation forces. 展开更多
关键词 POROUS Silicon Point Defects SELF-ORGANIZATION nanostructuring
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2024 aluminum alloy ultrahigh-strength sheet due to two-level nanostructuring under cryorolling and heat treatment 被引量:6
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作者 Stanislav KRYMSKIY Oleg SITDIKOV +1 位作者 Elena AVTOKRATOVA Michael MARKUSHEV 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第1期14-26,共13页
The effect of rolling to a total effective strain of 2 at the liquid nitrogen temperature and subsequent natural and artificial aging on the structure and service properties of the pre-quenched hot-pressed 2024 alumin... The effect of rolling to a total effective strain of 2 at the liquid nitrogen temperature and subsequent natural and artificial aging on the structure and service properties of the pre-quenched hot-pressed 2024 aluminum alloy was investigated.Using optical and electron microscopy,and X-ray analysis,it was found that the cryorolling did not qualitatively change the type of the initial coarse-fibered microstructure,but produced a well-developed nanocell substructure inside fibers.Further aging led to decomposition of the preliminary supersaturated and work-hardened aluminum solid solution and precipitation of strengthening phases in the statically recovered and/or recrystallized matrix.As a result,the rolled and naturally aged alloy demonstrated the yield and ultimate tensile strengths(YS=590 MPa,UTS=640 MPа)much higher than those in the pressed andТ6-heat treated alloy at equal elongation to failure(El^6%).Artificial aging at a temperature less than conventional T6 route could provide the extra alloy strengthening and the unique balance of mechanical properties,involving enhanced strength(YS=610 MPa,UTS=665 MPа)and ductility(El^10%),and good static crack resistance(the specific works for crack formation and growth were 42 and 18 k J/m^2,respectively)and corrosion resistance(the intensity and depth of intercrystalline corrosion were 23%and 50μm,respectively). 展开更多
关键词 aluminum alloy cryogenic rolling heat treatment NANOSTRUCTURE mechanical behavior intergranular corrosion
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Underwater persistent bubble-assisted femtosecond laser ablation for hierarchical micro/nanostructuring 被引量:12
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作者 Dongshi Zhang Bikas Ranjan +1 位作者 Takuo Tanaka Koji Sugioka 《International Journal of Extreme Manufacturing》 2020年第1期135-154,共20页
In this study,we demonstrate a technique termed underwater persistent bubble assisted femtosecond laser ablation in liquids(UPB-fs-LAL)that can greatly expand the boundaries of surface micro/nanostructuring through la... In this study,we demonstrate a technique termed underwater persistent bubble assisted femtosecond laser ablation in liquids(UPB-fs-LAL)that can greatly expand the boundaries of surface micro/nanostructuring through laser ablation because of its capability to create concentric circular macrostructures with millimeter-scale tails on silicon substrates.Long-tailed macrostructures are composed of layered fan-shaped(central angles of 45°–141°)hierarchical micro/nanostructures,which are produced by fan-shaped beams refracted at the mobile bubble interface(.50°light tilt,referred to as the vertical incident direction)during UPB-fs-LAL line-by-line scanning.Marangoni flow generated during UPB-fs-LAL induces bubble movements.Fast scanning(e.g.1mms−1)allows a long bubble movement(as long as 2mm),while slow scanning(e.g.0.1mms−1)prevents bubble movements.When persistent bubbles grow considerably(e.g.hundreds of microns in diameter)due to incubation effects,they become sticky and can cause both gas-phase and liquidphase laser ablation in the central and peripheral regions of the persistent bubbles.This generates low/high/ultrahigh spatial frequency laser-induced periodic surface structures(LSFLs/HSFLs/UHSFLs)with periods of 550–900,100–200,40–100 nm,which produce complex hierarchical surface structures.A period of 40 nm,less than 1/25th of the laser wavelength(1030 nm),is the finest laser-induced periodic surface structures(LIPSS)ever created on silicon.The NIR-MIR reflectance/transmittance of fan-shaped hierarchical structures obtained by UPB-fs-LAL at a small line interval(5μm versus 10μm)is extremely low,due to both their extremely high light trapping capacity and absorbance characteristics,which are results of the structures’additional layers and much finer HSFLs.In the absence of persistent bubbles,only grooves covered with HSFLs with periods larger than 100 nm are produced,illustrating the unique attenuation abilities of laser properties(e.g.repetition rate,energy,incident angle,etc)by persistent bubbles with different curvatures.This research represents a straightforward and cost-effective approach to diversifying the achievable hierarchical micro/nanostructures for a multitude of applications. 展开更多
关键词 hierarchical micro/nanostructures persistent bubble femtosecond laser surface structuring beam refraction fan-shaped microstructure LIPSS
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Enhancing thermoelectric performance in P-type Mg_(3)Sb_(2)-based Zintls through optimization of band gap structure and nanostructuring
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作者 Yi-bo Zhang Ji-Sheng Liang +6 位作者 Chengyan Liu Qi Zhou Zhe Xu Hong-bo Chen Fu-cong Li Ying Peng Lei Miao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第3期25-32,共8页
P-type Mg_(3)Sb_(2)-based Zintls have attracted considerable interest in the thermoelectric(TE)field due to their environmental friendliness and low cost.However,compared to their n-type counterparts,they show relativ... P-type Mg_(3)Sb_(2)-based Zintls have attracted considerable interest in the thermoelectric(TE)field due to their environmental friendliness and low cost.However,compared to their n-type counterparts,they show relatively low TE performance,limiting their application in TE devices.In this work,we simultaneously introduce Bi alloying at Sb sites and Ag doping at Mg sites into the Mg_(3)Sb_(2)to coopera-tively optimize the electrical and thermal properties for the first time,acquiring the highest ZT value of∼0.85 at 723 K and a high average ZT of 0.39 in the temperature range of 323-723 K in sample Mg_(2.94)Ag_(0.06)Sb_(1.9)Bi_(0.1).The first-principle calculations show that the codoping of Ag and Bi can shift the Fermi level into the valence band and narrow the band gap,resulting in the increased carrier concentration from 3.50×10^(17)cm^(-3)in the reference Mg 3 Sb 0.9 Bi 0.1 to∼7.88×10^(19)cm^(-3)in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi 0.1.As a result,a remarkable power factor of∼778.9μW m^(-1)K^(-2)at 723 K is achieved in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi 0.1.Meanwhile,a low lattice thermal conductivity of∼0.48 W m^(-1)K^(-1)at 723 K is also obtained with the help of phonon scattering at the distorted lattice,point defects,and nano-precipitates in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi 0.1.The synergistic effect of using the multi-element co-doping/-alloying to optimize electrical properties in Mg_(3)Sb_(2)holds promise for further improving the TE performance of Zintl phase materials or even others. 展开更多
关键词 Thermoelectric materials Band engineering nanostructuring P-type Mg_(3)Sb_(2) Ag and Bi Co-doping
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Innovative Solutions for High-Performance Silicon Anodes in Lithium-Ion Batteries:Overcoming Challenges and Real-World Applications 被引量:1
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作者 Mustafa Khan Suxia Yan +6 位作者 Mujahid Ali Faisal Mahmood Yang Zheng Guochun Li Junfeng Liu Xiaohui Song Yong Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期341-384,共44页
Silicon(Si)has emerged as a potent anode material for lithium-ion batteries(LIBs),but faces challenges like low electrical conductivity and significant volume changes during lithiation/delithiation,leading to material... Silicon(Si)has emerged as a potent anode material for lithium-ion batteries(LIBs),but faces challenges like low electrical conductivity and significant volume changes during lithiation/delithiation,leading to material pulverization and capacity degradation.Recent research on nanostructured Si aims to mitigate volume expansion and enhance electrochemical performance,yet still grapples with issues like pulverization,unstable solid electrolyte interface(SEI)growth,and interparticle resistance.This review delves into innovative strategies for optimizing Si anodes’electrochemical performance via structural engineering,focusing on the synthesis of Si/C composites,engineering multidimensional nanostructures,and applying non-carbonaceous coatings.Forming a stable SEI is vital to prevent electrolyte decomposition and enhance Li^(+)transport,thereby stabilizing the Si anode interface and boosting cycling Coulombic efficiency.We also examine groundbreaking advancements such as self-healing polymers and advanced prelithiation methods to improve initial Coulombic efficiency and combat capacity loss.Our review uniquely provides a detailed examination of these strategies in real-world applications,moving beyond theoretical discussions.It offers a critical analysis of these approaches in terms of performance enhancement,scalability,and commercial feasibility.In conclusion,this review presents a comprehensive view and a forward-looking perspective on designing robust,high-performance Si-based anodes the next generation of LIBs. 展开更多
关键词 Silicon anode Energy storage NANOSTRUCTURE Prelithiation BINDER
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A mini review: Functional nanostructuring with perfectly-ordered anodic aluminum oxide template for energy conversion and storage 被引量:7
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作者 Huaping Zhao Long Liu Yong Lei 《Frontiers of Chemical Science and Engineering》 SCIE EI CAS CSCD 2018年第3期481-493,共13页
Nanostructures have drawn great attentions for functional device applications. Among the various techniques developed for fabricating arrayed nanostructures of functional materials, nanostructuring technique with poro... Nanostructures have drawn great attentions for functional device applications. Among the various techniques developed for fabricating arrayed nanostructures of functional materials, nanostructuring technique with porous anodic aluminum oxide (AAO) membrane as templates becomes more attractive owing to the superior geometrical characteristics and low-cost preparation process. In this mini review, progress about functional we summarize our recent nanostructuring based on perfectly-ordered AAO membrane to prepare perfectly- ordered nanostructure arrays of functional materials toward constructing high-performance energy conversion and storage devices. By employing the perfectly-ordered AAO membrane as templates, arrayed nanostructures in the form ofnanodot, nanorod, nanotube and nanopore have been synthesized over a large area. These as-obtained nanostructure arrays have large specific surface area, high regularity, large-scale implementation, and tunable nanos- cale features. All these advanced features enable them to be of great advantage for the performance improvement of energy conversion and storage devices, including photo- electrochemical water splitting cells, supercapacitors, and batteries, etc. 展开更多
关键词 nanostructuring perfectly-ordered AAO template photoelectrochemical water splitting sodium-ion batteries SUPERCAPACITORS
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Crystallization Behaviour and Nanostructuring in Alkali Niobiosilicate Glasses 被引量:1
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作者 E.Fanelli P.Pernice +2 位作者 M.Xiao A.Aronne V.N.Sigaev 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第2期189-192,共4页
23K2O·27Nb2O5·50SiO 2(KNS),13K2O·10Na2O·27Nb2O5·50SiO 2(KNaNS) and 15K2O·12Li2O·27Nb2O5·46SiO2(KLiNS) transparent glasses were synthesized by melt-quenching technique,and ... 23K2O·27Nb2O5·50SiO 2(KNS),13K2O·10Na2O·27Nb2O5·50SiO 2(KNaNS) and 15K2O·12Li2O·27Nb2O5·46SiO2(KLiNS) transparent glasses were synthesized by melt-quenching technique,and studied by differential thermal analysis(DTA),X-ray diffraction(XRD) and high-resolution transmission electron microscopy(HRTEM) to reveal the effect of the devitrification behaviour on transparent nanostructure.Just above the glass transition temperature T g in the KNS glass,an unidentified phase was formed,while in KNaNS and KLiNS,mixed-alkali niobate phases with tungsten bronze structure were obtained by bulk crystallization.Heat treatments at T g performed on the KNS glass resulted in the transparent nanostructure with second order harmonic generation(SHG) activity.Heat treatment for 10 h on KNaNS and KLiNS decreased the first DTA exothermic peaks(at least 24C),indicating the bulk nucleation,which was confirmed by the DTA in comparison with the powdered as-quenched samples.KNaNS and KLiNS showed similar XRD profiles as the K3Li2Nb5O15 crystal with the five most intense peaks at 22.7,29.4,32.3,46.3 and 52.0 deg.HRTEM micrograph showed clear-cut nano-sized circular domains and spherical nanocrystals dispersed into the amorphous matrix. 展开更多
关键词 Niobiosilicate glasses CRYSTALLIZATION nanostructuring
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Recent progress on nanomaterial-based electrochemical dissolved oxygen sensors
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作者 Shaoqi Zhang Tao Liu +1 位作者 Zhenyu Chu Wanqin Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期103-119,共17页
Dissolved oxygen(DO)usually refers to the amount of oxygen dissolved in water.In the environment,medicine,and fermentation industries,the DO level needs to be accurate and capable of online monitoring to guide the pre... Dissolved oxygen(DO)usually refers to the amount of oxygen dissolved in water.In the environment,medicine,and fermentation industries,the DO level needs to be accurate and capable of online monitoring to guide the precise control of water quality,clinical treatment,and microbial metabolism.Compared with other analytical methods,the electrochemical strategy is superior in its fast response,low cost,high sensitivity,and portable device.However,an electrochemical DO sensor faces a trade-off between sensitivity and long-term stability,which strongly limits its practical applications.To solve this problem,various advanced nanomaterials have been proposed to promote detection performance owing to their excellent electrocatalysis,conductivity,and chemical stability.Therefore,in this review,we focus on the recent progress of advanced nanomaterial-based electrochemical DO sensors.Through the comparison of the working principles on the main analysis techniques toward DO,the advantages of the electrochemical method are discussed.Emphasis is placed on recently developed nanomaterials that exhibit special characteristics,including nanostructures and preparation routes,to benefit DO determination.Specifically,we also introduce some interesting research on the configuration design of the electrode and device,which is rarely introduced.Then,the different requirements of the electrochemical DO sensors in different application fields are included to provide brief guidance on the selection of appropriate nanomaterials.Finally,the main challenges are evaluated to propose future development prospects and detection strategies for nanomaterial-based electrochemical sensors. 展开更多
关键词 NANOMATERIAL Dissolved oxygen Electrochemical sensor NANOSTRUCTURES Detection principles
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Modeling the performance of perovskite solar cells with inserting porous insulating alumina nanoplates
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作者 潘赵耀 杨金彭 沈小双 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期668-671,共4页
Peng et al.[Science 379683(2023)]reported an effective method to improve the performance of perovskite solar cells by using thicker porous insulator contact(PIC)-alumina nanoplates.This method overcomes the trade-off ... Peng et al.[Science 379683(2023)]reported an effective method to improve the performance of perovskite solar cells by using thicker porous insulator contact(PIC)-alumina nanoplates.This method overcomes the trade-off between the open-circuit voltage and the fill factor through two mechanisms:reduced surface recombination velocity and increased bulk recombination lifetime due to better perovskite crystallinity.From arguments of drift-diffusion simulations,we find that an increase in mobility and carrier recombination lifetime in bulk are the key factors for minimizing the resistance-effect from thicker PICs and achieving a maximum power conversion efficiency(PCE)at approximately 25%reduced contact area.Furthermore,the partially replacement of perovskite films with thicker PICs would result in a reduction in short-current density,but the relative low refractive index of the PICs imbedded into the high refractive index perovskite creates light trapping structures that compensate for this loss. 展开更多
关键词 perovskite solar cells NANOSTRUCTURE CRYSTALLINE mobility
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Effect of trace oxygen on plasma nitriding of titanium foil
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作者 周海涛 熊希雅 +3 位作者 马可欣 罗炳威 罗飞 申承民 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期548-551,共4页
Titanium nitride films are prepared by plasma enhanced chemical vapor deposition method on titanium foil using N_(2) as precursor. In order to evaluate the effect of oxygen on the growth of titanium nitride films, a s... Titanium nitride films are prepared by plasma enhanced chemical vapor deposition method on titanium foil using N_(2) as precursor. In order to evaluate the effect of oxygen on the growth of titanium nitride films, a small amount of O_(2) is introduced into the preparation process. The study indicates that trace O_(2) addition into the reaction chamber gives rise to significant changes on the color and micro-morphology of the foil, featuring dense and long nano-wires. The as-synthesized nanostructures are characterized by various methods and identified as TiN, Ti_(2) N, and TiO_(2) respectively. Moreover, the experiment results show that oxide nanowire has a high degree of crystallinity and the nitrides present specific orientation relationships with the titanium matrix. 展开更多
关键词 NITRIDE OXIDE NANOSTRUCTURE CRYSTALLINE plasma-enhanced chemical vapor deposition system(PECVD)
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Synthesis of boron nitride nanorod and its performance as a metalfree catalyst for oxidative desulfurization of diesel fuel
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作者 Tanaz Ghanadi Gholamreza Moradi Alimorad Rashidi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期120-132,共13页
In order to reduce the sulfur compounds in diesel fuel,boron nitride(BN)has been used as a novel metal-free catalyst in the present research.This nanocatalyst was synthesized via template-free approach followed by hea... In order to reduce the sulfur compounds in diesel fuel,boron nitride(BN)has been used as a novel metal-free catalyst in the present research.This nanocatalyst was synthesized via template-free approach followed by heating treatment at 900℃ in nitrogen atmosphere that the characteristics of the sample were identified by the X-ray diffraction,Fourier-transform infrared spectroscopy,Raman spectroscopy,field emission scanning electron microscopy,transmission electron microscopy,atomic force microscopy,and N2 adsorption-desorption isotherms.The results of structural and morphological analysis represented that BN has been successfully synthesized.The efficacy of the main operating parameters on the process was studied by using response surface methodology based on the Box-Behnken design method.The prepared catalyst showed high efficiency in oxidative desulfurization of diesel fuel with initial sulfur content of 8040 mg·kg^(-1)S.From statistical analysis,a significant quadratic model was obtained to predict the sulfur removal as a function of efficient parameters.The maximum efficiency of 72.4%was achieved under optimized conditions at oxidant/sulfur molar ratio of 10.2,temperature of 71℃,reaction time of 113 min,and catalyst dosage of 0.36 g.Also,the reusability of the BN was studied,and the result showed little reduction in activity of the catalyst after 10 times regeneration.Moreover,a plausible mechanism was proposed for oxidation of sulfur compounds on the surface of the catalyst.The present study shows that BN materials can be selected as promising metal-free catalysts for desulfurization process. 展开更多
关键词 DESULFURIZATION Boron nitride(BN)nanostructure Experimental design BoxeBehnken
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Formation of Natural Melanin/TiO_(2) Nanostructure Hybrids with Enhanced Optical,Thermal and Magnetic Properties as a Soft Material
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作者 Saja Algessair Nawal Madkhali 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期613-620,共8页
The natural Melanin/TiO_(2) was synthesized by the use of ultrasonication under UV radiation.The influence of natural melanin on the structural,optical and thermal properties of TiO_(2) nanoparticles was investigated ... The natural Melanin/TiO_(2) was synthesized by the use of ultrasonication under UV radiation.The influence of natural melanin on the structural,optical and thermal properties of TiO_(2) nanoparticles was investigated by using Fourier transform infrared spectroscopy,thermogravimetric analysis and UV-Vis spectroscopy.It was observed that incorporating natural melanin on TiO_(2) nanoparticles(TiO_(2)-Mel)occurred at 2.01 eV with a low value of Urbach energy around 100 meV indicating improvement in the crystalline structure.Magnetic measurement at room temperature showed diamagnetic behavior.Furthermore,thermal results showed that TiO_(2)-Mel is stable even at temperatures up to 400℃.According to the results obtained by the thermal stability of melanin with titanium dioxide,it can be a good candidate in many applications such as solar cells and optoelectronics. 展开更多
关键词 natural melanin/TiO_(2) thermal stability OPTOELECTRONIC NANOSTRUCTURE UV radiation
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First-principles study of electronic and magnetic properties of Fe atoms on Cu_(2)N/Cu(100)
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作者 陈佳乐 胡军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期498-503,共6页
First-principles calculations were conducted to investigate the structural,electronic,and magnetic properties of single Fe atoms and Fe dimers on Cu_(2)N/Cu(100).Upon adsorption of an Fe atom onto Cu_(2)N/Cu(100),robu... First-principles calculations were conducted to investigate the structural,electronic,and magnetic properties of single Fe atoms and Fe dimers on Cu_(2)N/Cu(100).Upon adsorption of an Fe atom onto Cu_(2)N/Cu(100),robust Fe-N bonds form,resulting in the incorporation of both single Fe atoms and Fe dimers within the surface Cu_(2)N layer.The partial occupancy of Fe-3d orbitals lead to large spin moments on the Fe atoms.Interestingly,both single Fe atoms and Fe dimers exhibit in-plane magnetic anisotropy,with the magnetic anisotropy energy(MAE)of an Fe dimer exceeding twice that of a single Fe atom.This magnetic anisotropy can be attributed to the predominant contribution of the component along the x direction of the spin-orbital coupling Hamiltonian.Additionally,the formation of Fe-Cu dimers may further boost the magnetic anisotropy,as the energy levels of the Fe-3d orbitals are remarkably influenced by the presence of Cu atoms.Our study manifests the significance of uncovering the origin of magnetic anisotropy in engineering the magnetic properties of magnetic nanostructures. 展开更多
关键词 magnetic nanostructures magnetic anisotropy spin–orbital coupling ultrathin substrate
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Integrated adsorption and photocatalytic removal of methylene blue dye from aqueous solution by hierarchical Nb_(2)O_(5)@PAN/PVDF/ANO composite nanofibers
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作者 Aditya Rianjanu Kurniawan Deny Pratama Marpaung +8 位作者 Elisabeth Kartini Arum Melati Rizky Aflaha Yudha Gusti Wibowo I Putu Mahendra Nursidik Yulianto Januar Widakdo Kuwat Triyana Hutomo Suryo Wasisto Tarmizi Taher 《Nano Materials Science》 EI CAS CSCD 2024年第1期96-105,共10页
This work presents the development of hierarchical niobium pentoxide(Nb_(2)O_(5))-based composite nanofiber membranes for integrated adsorption and photocatalytic degradation of methylene blue(MB)pollutants from aqueo... This work presents the development of hierarchical niobium pentoxide(Nb_(2)O_(5))-based composite nanofiber membranes for integrated adsorption and photocatalytic degradation of methylene blue(MB)pollutants from aqueous solutions.The Nb_(2)O_(5) nanorods were vertically grown using a hydrothermal process on a base electrospun nanofibrous membrane made of polyacrylonitrile/polyvinylidene fluoride/ammonium niobate(V)oxalate hydrate(Nb_(2)O_(5)@PAN/PVDF/ANO).They were characterized using field-emission scanning electron microscopy(FE-SEM),X-ray diffraction(XRD)analysis,and Fourier transform infrared(FTIR)spectroscopy.These composite nanofibers possessed a narrow optical bandgap energy of 3.31 eV and demonstrated an MB degradation efficiency of 96%after 480 min contact time.The pseudo-first-order kinetic study was also conducted,in which Nb_(2)O_(5)@PAN/PVDF/ANO nanofibers have kinetic constant values of 1.29×10^(-2) min^(-1) and 0.30×10^(-2) min^(-1) for adsorption and photocatalytic degradation of MB aqueous solutions,respectively.These values are 17.7 and 7.8 times greater than those of PAN/PVDF/ANO nanofibers without Nb_(2)O_(5) nanostructures.Besides their outstanding photocatalytic performance,the developed membrane materials exhibit advantageous characteristics in recycling,which subsequently widen their practical use in environmental remediation applications. 展开更多
关键词 Hierarchical nanostructure Composite nanofiber Niobium pentoxide Dye degradation Synergetic adsorption and photocatalysis
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Universal architecture and defect engineering dual strategy for hierarchical antimony phosphate composite toward fast and durable sodium storage
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作者 Jiawei Wu Gaoyu Wang +7 位作者 Wei Zhang Lixiang Wang Jian Peng Qinghua Li Zhixin Liang Wenbo Fan Jiazhao Wang Shaoming Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期110-119,I0004,共11页
Antimony(Sb)-ba sed anode materials are feasible candidates for sodium-ion batteries(SIBs) due to their high theoretical specific capacity and excellent electrical conductivity.However,they still suffer from volume di... Antimony(Sb)-ba sed anode materials are feasible candidates for sodium-ion batteries(SIBs) due to their high theoretical specific capacity and excellent electrical conductivity.However,they still suffer from volume distortion,structural collapse,and ionic conduction interruption upon cycling.Herein,a hierarchical array-like nanofiber structure was designed to address these limitations by combining architecture engineering and anion tuning strategy,in which SbPO_(4-x) with oxygen vacancy nanosheet arrays are anchored on the surface of interwoven carbon nanofibers(SbPO_(4-x)@CNFs).In particular,bulky PO_(4)^(3-) anions mitigate the large volume distortion and generate Na_(3)PO_(4) with high ionic conductivity,collectively improving cyclic stability and ionic transport efficiency.The abundant oxygen vacancies substantially boost the intrinsic electronic conductivity of SbPO_4,further accelerating the reaction dynamics.In addition,hierarchical fibrous structures provide abundant active sites,construct efficient conducting networks,and enhance the electron/ion transport capacity.Benefiting from the advanced structural design,the SbPO_(4-x)@CNFs electrodes exhibit outstanding cycling stability(1000 cycles at 1.0 A g^(-1) with capacity decay of 0.05% per cycle) and rapid sodium storage performance(293.8 mA h g^(-1) at 5.0 A g^(-1)).Importantly,systematic in-/ex-situ techniques have revealed the "multi-step conversion-alloying" reaction process and the "battery-capacitor dual-mode" sodium-storage mechanism.This work provides valuable insights into the design of anode materials for advanced SIBs with elevated stability and superior rate performance. 展开更多
关键词 SbPO_(4) anodes Hierarchical nanostructures Oxygen vacancy Stress dispersion Sodium-ion batteries
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Ambient-Condition Strategy for Production of Hollow Ga_(2)O_(3)@rGO Crystalline Nanostructures Toward Efficient Lithium Storage
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作者 Dongdong Zhang Qiliang Wei +7 位作者 Haili Huang Lan Jiang Jie Teng Ruizhi Yu Qing Zhang Shengxing Liu Lin Wang Weiyou Yang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期75-82,共8页
Crystallineγ-Ga_(2)O_(3)@rGO core-shell nanostructures are synthesized in gram scale,which are accomplished by a facile sonochemical strategy under ambient condition.They are composed of uniformγ-Ga_(2)O_(3)nanosphe... Crystallineγ-Ga_(2)O_(3)@rGO core-shell nanostructures are synthesized in gram scale,which are accomplished by a facile sonochemical strategy under ambient condition.They are composed of uniformγ-Ga_(2)O_(3)nanospheres encapsulated by reduced graphene oxide(rGO)nanolayers,and their formation is mainly attributed to the existed opposite zeta potential between the Ga_(2)O_(3)and rGO.The as-constructed lithium-ion batteries(LIBs)based on as-fabricatedγ-Ga_(2)O_(3)@rGO nanostructures deliver an initial discharge capacity of 1000 mAh g^(-1)at 100 mA g^(-1)and reversible capacity of 600 mAh g^(-1)under 500 mA g^(-1)after 1000 cycles,respectively,which are remarkably higher than those of pristineγ-Ga_(2)O_(3)with a much reduced lifetime of 100 cycles and much lower capacity.Ex situ XRD and XPS analyses demonstrate that the reversible LIBs storage is dominant by a conversion reaction and alloying mechanism,where the discharged product of liquid metal Ga exhibits self-healing ability,thus preventing the destroy of electrodes.Additionally,the rGO shell could act robustly as conductive network of the electrode for significantly improved conductivity,endowing the efficient Li storage behaviors.This work might provide some insight on mass production of advanced electrode materials under mild condition for energy storage and conversion applications. 展开更多
关键词 ambient condition core-shell nanostructures Ga_(2)O_(3) Li-ion batteries rGO
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