查看更多>>摘要：The LiNi0.83Co0.12Mn0.05O2(Ni-rich NCM)cathode materials have been widely studied owing to their high energy density and excellent rate capability.However,Ni-rich NCM is prone to form large amounts of lithium impurities and causes structural decline,resulting in inconvenient material storage.To this end,Li4SiO4/SiO2 was used as a structural regulator to eliminate the residual lithium and convert the irreversible phase.The Li4SiO4/SiO2 pro-tective coating effectively suppresses the corrosion of the electrolyte by blocking the direct contact between the electrode and the electrolyte,while having a high air stability under the hydrophobic action.In addition,SiO2 has excellent corrosion resistance,which further enhances the cyclic stability of the material.The obtained regen-erated NCM material displayed a great capacity of 198.6 mAh g-1 at 0.3 C and long cycling stability(capacity retention of 82.2％after 250 cycles).This simple repair strategy significantly reduces the loss rate in industrial production and enhances the electrochemical performance while achieving material reuse.
查看更多>>摘要：This study focused on the microscopic strengthening and failure mechanisms of the Al matrix reinforced by graphene(Gr),and the effects of number of layers,chirality,and arrangement of Gr were calculated based on the molecular dynamics simulation.The results revealed that the Young's modulus and yield strength were signifi-cantly enhanced by the addition of Gr.In Gr/Al composites with monolayer Gr,the zigzag Gr exhibited a better ultimate strain than the armchair Gr,indicating that the plastic deformation was affected by the chirality,and the dislocation hindrance and load transfer were the dominated strengthening mechanisms.The crack in the armchair Gr was limited to follow straight paths,while that in zigzag Gr extended in a petal-like manner across multiple directions.In Gr/Al composite with multilayer Gr,the dispersing Gr showed a stronger strengthening effect than the stacking Gr,and the strengthening effect increased with increasing the volume fraction of Gr.The dispersing Gr strongly hindered the movement of dislocations,while the Al matrix in the composite with stacking Gr could retard the folding of Gr.Moreover,Gr nanosheets fractured layer by layer rather than simultaneously fractured in the Gr/Al composites with multilayer Gr.
Lu ZhangHarry Lye Hin ChongDan LuoSalah M.El-Bahy...
731-738页
查看更多>>摘要：Faradic-based capacitive deionization(FDI)has been widely acknowledged as one of the most promising desa-lination techniques to solve the freshwater crisis,yet was largely limited by heavily trailed development of its anode materials,which subsequently hindered its desalination performance in terms of both desalination capacity and stability.Herein,we developed a new type of anode material for FDI by coupling chloride-insertion FeOOH with carbon nanotubes(CNTs@FeOOH).The essence of this study lay in the composition of FeOOH with CNTs that could not only facilitate charge/electron transfer but also prevent structural aggregation.Consequently,the CNTs@FeOOH-based FDI system displays excellent desalination performance(desalination capacity:50.36 mg g-1;desalination rate:0.41 mg g-1 s-1)with robust long-term stability(13.86％reduction over 80 cycles),which could motivate the future development of other highly-efficient desalination systems.
查看更多>>摘要：Silicon monoxide(SiOx)has garnered considerable attention as an anode material owing to its high capacity.Nevertheless,its commercial viability is hampered by the low conductivity and inadequate cycling stability.In this study,a micrometer-scale silicon oxide/carbon composite(1000-SiOx/NC)was developed based on the porous and high electrical conductivity of pyrolyzed polydopamine(PDA)and the high-temperature dispropor-tionation of SiOx.Electrochemical impedance spectroscopy(EIS)and X-ray photoelectron spectroscopy(XPS)analyses confirmed that the pyrolysis of polydopamine(PDA)not only improves electrode conductivity but also contributes to the formation of a stable solid electrolyte interface(SEI).Additionally,SiOx undergoes dispro-portionation reactions during the pyrolysis of PDA,further the improves the cyclic stability of the composites.Consequently,the 1000-SiOx/NC composite electrode exhibited an impressive specific capacity of 783.4 mAh·g-1 after 500 cycles at 1 A g-1,maintaining 80.1％of its initial capacity.Additionally,at a high rate of 3 C,its capacity reached 607.3 mAh·g-1 The synthesis approach is both straightforward and economical,offering a fresh avenue for the widespread commercial deployment of SiOx.
查看更多>>摘要：CuO coating layers have attracted numerous attention due to its wide application in catalysis,batteries and other areas.However,the uncontrollable precipitation process of Cu2+has made it challenging to form uniform CuO nanoshells.In this study,uniform CuO nanoshells were prepared through a delicate design.Namely,the uniform Cu2+-poly(m-phenylenediamine)(Cu-PmPD)nanoshells were constructed firstly,and then the organic parts in the Cu-PmPD were removed while uniform CuO nanoshells formed in the controllable calcination process.Applying this method to high-voltage cathode materials,the CuO was successfully coated on the LiNi0.5Mn1.5O4,which greatly reduced the transition metal dissolution and improved the electrochemical performance in lithium-ion batteries.
查看更多>>摘要：The impact of different Ta contents on the mechanical properties and thermoplastic forming ability of in-situ Ta-particle reinforced Zr-Cu-Al-Ni bulk metallic glass composites was studied.The composition(Zr55Cu30Ali0-Ni5)94Ta6 with the best comprehensive performance was chose for a systematic investigation into its thermo-plastic behavior in the supercooled liquid region(SLR),with quantitative analysis conducted by the strain rate sensitivity index and activation volume.The steady-state flow stress and the stress overshoot intensity were augmented with deformation temperature decreasing,strain rate increasing,and the addition of the secondary phase,leading to a transition from Newtonian to non-Newtonian flow regime.The addition of the secondary phase deteriorated the theological properties of the material.To solve the problem that the Maxwell-Pulse constitutive model showed an inability to accurately describe the steady-state flow process.A modified consti-tutive relationship,introducing the effect of the volume fraction of Ta particles on viscosity and elastic modulus in the steady-state flow process which was ignored in Maxwell-pulse model,was established.The fitting results of the true stress-strain curves of the modified Maxwell-pulse constitutive model were in better agreement with the experimental date than those of the Maxwell-pulse constitutive model,with higher prediction accuracy.The modified constitutive model well predicted the thermoplastic deformation behavior of(Zr55Cu30Al10Ni5)94Ta6.The influence mechanism of Ta particles on the flow behavior was explained that Ta particles increased the viscosity of amorphous matrix,thereby hindering its flow and ultimately leading to an increase in flow stress.
查看更多>>摘要：Utilizing solar energy to decompose tetracycline(TC)is a green strategy to treat wastewater.Herein,a hetero-geneous hollow structured TiO2 decorated Pt nanoparticles were successfully designed and synthesized via hard-template approach and photo-deposition process toward TC photodegradation.The Pt nanoparticles loaded on the surface of hollow structured TiO2 can increase the visible light absorption due to the local surface plasmon resonance(LSPR)effect.Furthermore,owing to the tough electron oscillation of the LSPR excitation,the plas-monic hot holes on the surface of Pt nanoparticles can capture the electrons of TiO2,effectively facilitating the separation of photo-excited charge carriers because of the formation of Schottky junction constructed between Pt and TiO2.Combined the natural merits of shorten conveying path of charge carriers and physical structural stability for hollow structure,the optimal Pt/TiO2 hetero-junction hybrid showed superior photocatalytic activity and durability for TC photodegradation with the degradation efficiency of 93.8％after 30 min and the rate constant of 0.09196 min-1 under 300 W Xe lamp irradiation.This work displays a heterogeneous hybrids catalyst based on eco-friendly metal and semiconductor materials which can be used in the fields including without limitation TC photodegradation.
查看更多>>摘要：Transitional metal oxides are excellent candidates as heterogeneous catalysts for activating persulfate towards organics degradation.In this study,MnCo2O4 spinel was successfully prepared using a solvent-free molten method.The catalytic performance was systematically investigated and MnCo2O4 powder catalyst was success-fully immobilized on polyurethane(PU)membrane through electrospinning to assess its application potential.The results showed that peroxymonosulfate(0.1 g L-1)activated by MnC02O4(0.1 g L-1)reached 99.92％degradation in 10 min when treating 0.04 g L-1 rhodamine B as target pollutant.The abundant oxygen vacancies formation,synergistic effect of Co and Mn ions and high electron transfer mobility are contributing to production of reactive oxygen species.Combining with quenching experiment and time-resolved EPR,the contribution of various active species was proposed,of which 1O2 exhibited the dominant role.The flowing reaction run by the MnCo2O4-PU membrane activating PMS exhibited universal degradation on different target pollutants.
查看更多>>摘要：Using melt spinning technology,we successfully synthesized a series of Fe-rich Fe-P-C amorphous alloys exhibiting high saturation magnetization(Bs),low coercivity(Hc),and excellent bending ductility.These alloys exhibit low Hc values ranging from 4.1 to 7.2 A/m,and high Bs values ranging from 1.58 to 1.68 T.Particularly,after annealing at 588 K for 900 s,the Fe83P11C6 amorphous alloy showed extraordinary soft magnetic properties:Bs up to 1.68 T,Hc only 4.7 A/m,and the core loss at approximately 1.5 W/kg under the condition of 0.5 T and 50 Hz,all of which surpass the reported Fe-P-C ternary amorphous and nanocrystalline alloys.These Fe-rich Fe-P-C alloy ribbon samples exhibit favorable bending ductility in both the as-spun and annealed states.Their simple alloy composition,outstanding soft magnetic properties,and excellent flexibility collectively make these soft magnetic alloys highly promising candidate materials for industrial applications.
查看更多>>摘要：The dual-phase competitive behavior is introduced as an effective strategy to optimize the physical and chemical properties of N-type Bi2Te3 thermoelectric(TE)materials.Controllable SnTe-embedded Bi2Te3 nanocomposites can be synthesized with the addition of excessive Sn into Bi2Te3 by tuning the crystallization behavior under proper thermal heating temperature.Notably,the precipitation temperature of Bi2Te3 increases from 473 K for Sn20.9(Bi2Te3)79.1 to 573 K for Sn34.4(Bi2Te3)65.6,expanding the controllable temperature span for the presence of SnTe phase.The second-phase nanoprecipitate SnTe can improve electrical conductivity by competing with the Bi2Te3 phase,achieving an increase of four orders of magnitude at the critical temperature of～500 K.Simul-taneously,it increases the interfacial energy filtration effect between nanocrystalline grains,decoupling electrical parameters between conductivity and Seebeck coefficient.Consequently,the high power factor of～147 μW/mK2 at 650 K for optimized Sn26.6(Bi2Te3)73.4 films can be obtained,which is more than twice that of the pure Bi2Te3 material.Our work demonstrates a new physical mechanism to unravel the complicated structure-property relationship by dual-phase competitive behavior during phase transition.This study fills the gap in knowledge on the effects of the SnTe phase regarding the Bi2Te3 system and provides guidance for the innovative design of high-performing inorganic thermoelectrics.
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