A multi-kernel-shell indium selenide@carbon nanosphere enabling high-performance lithium-ion batteries

Indium selenide has garnered significant attention for high volumetric capacities,but is currently plagued by the sluggish charge transfer kinetics,severe volume effect,and rapid capacity degradation that hinder their practical applications.Herein,we design,synthesize,and characterize a multi-kernel-shell structure comprised of indium selenide encapsulated within carbon nanospheres(referred to as m-K-S In_(2)Se_(3)@C)through an integrated approach involving a hydrothermal method followed by a gaseous selenization process.Importantly,experimental measurements and density functional theory calculations confirm that the m-K-S In_(2)Se_(3)@C not only improve the adsorption capability for Li-ions but also lower the energy barrier for Li-ions diffusion.Profiting from numerous contact points,shorter diffusion distances and an improved volume buffering effect,the m-K-S In_(2)Se_(3)@C achieves an 800 mA h g^(−1)capacity over 1000 loops at 1000 mA g^(−1),a 520 mA h g^(−1)capacity at 5000 mA g^(−1)and an energy density of 270 Wh kg^(−1)when coupled with LiFePO4,surpassing most related anodes reported before.Broadly,the m-K-S structure with unique nano-micro structure offers a new approach to the design of advanced anodes for LIBs.

Recent developments in high-strength Mg-RE-based alloys:Focusing on Mg-Gd and Mg-Y systems

Higher strength is always the goal pursued by researchers for the structural materials,especially for the lightweight magnesium(Mg)alloys which generally have relatively low strength at present.From this aspect,the present paper reviews the recent reports of a kind of Mg alloys,i.e.Mg-RE(RE:rare earths,mainly Gd or Y)casting and wrought alloys,which have been able to achieve high strength compared with common or commercial Mg alloys,from the viewpoint and content of the alloy system,alloying constitution,preparation process,tensile strength and each of the main strengthening mechanisms.This review of recent research and developments in high-strength Mg-RE alloys is beneficial for the further design of Mg alloys with higher strength as well as excellent comprehensive performance.

Trending IC design directions in 2022

For the non-stop demands for a better and smarter society, the number of electronic devices keeps increasing exponentially;and the computation power, communication data rate, smart sensing capability and intelligence are always not enough. Hardware supports software, while the integrated circuit(IC) is the core of hardware. In this long review paper, we summarize and discuss recent trending IC design directions and challenges, and try to give the readers big/cool pictures on each selected small/hot topics. We divide the trends into the following six categories, namely, 1) machine learning and artificial intelligence(AI) chips, 2) communication ICs, 3) data converters, 4) power converters, 5) imagers and range sensors, 6) emerging directions. Hope you find this paper useful for your future research and works.

Mathematical analysis and its experimental comparisons for the accumulative roll bonding(ARB)process with different superimposed layers

Based on the traditional two-layer accumulative roll bonding(TARB),the geometrical variations and mathematical relationship during the four-layer accumulative roll bonding(FARB)were derived and summarized.Furthermore,the multi-layer accumulative roll bonding(MARB)technology was proposed and the geometrical variations and mathematical relationship of MARB were simultaneously derived and summarized.Experimentally,Mg-14Li-3Al-2Gd(LAGd1432)sheets were fabricated by TARB and FARB,respectively.Compared with the TARB,the FARB has a higher accumulative efficiency in terms of accumulative layers,total number of interfaces,interface spacing,total deformation and equivalent strain.Therefore,the FARB-processed sheets in lower cycles have the similar microstructure and mechanical properties of the TARB-processed sheets in higher cycles.In addition,FARB process can further break through the deformation limit of TARB process in a single cycle through adopting two-step rolling in one cycle with 50%deformation in one pass and 75%accumulative deformation in one cycle,which can effectively solve the problem of poor interface bonding of the latest interface brought by the last cycle,and thus significantly improve the phenomenon of unstable performance of the ARB-processed sheets.

Fabrication of agarose hydrogel with patterned silver nanowiresfor motion sensor

In this work, a facile strategy is proposed to construct stretchable electronics based on agarose hydrogels. The hot agarose solution is casted onto a template with patterned Ag nanowires, endowing agarose hydrogel with patterned conductive surface. After further heating treatment, Ag nanowires can be embedded into the agarose hydrogel, which improves the stability of Ag pattern and has no obvious e ffect on the conductivity of hydrogels. The agarose hydrogel with patterned Ag nanowires is certi fied to be an e ffective stretchable electrode to record the motion of joints, which has great potential applications in the field of wearable devices.

Influence of rolling directions on microstructure,mechanical properties and anisotropy of Mg-5Li-1Al-0.5Y alloy

Mg-5Li-1Al-0.5Y alloy was rolled with different directions.The microstructure,mechanical properties and texture of the specimens were investigated with optical microscope,tensile tester and X-ray diffraction.The results show that changing rolling directions can refine the grain size of as-rolled alloys.Meanwhile,rolling directions have an obvious influence on the mechanical properties and texture of Mg-5Li-1Al-0.5Y alloy,thus affecting the anisotropy of the alloy.The sheet,of which the RD(rolling direction)and ND(normal direction)are both changed between two passes,possesses the smallest anisotropy.From the texture results,changing rolling directions reduces the maximum pole density,making the highest point distribution region excursion and the highest point distributes more scatteredly.

Relationship between equilibrium potential and radius of lanthanides electrolyzed on the zinc cathode

The electrochemical behavior of lanthanide elements deposited on liquid zinc cathodes was studied using cyclic voltammetry(CV)and open circuit chronopotentiometry(OCP).We observed a"bimodal effect"in the equilibrium deposition potentials of zinc with lanthanides.A mathematic equation is derived to illustrate the relationship between the equilibrium potential of the intermetallic compounds formed by lanthanide elements and zinc and their atomic radius.This equation is not only applicable to lanthanide elements but also hold for other elements such as alkali metal lithium,alkaline earth metal magnesium,calcium and transition metal niobium,which have crucial theoretical significance for the electrolysis of intermetallic compounds,the separation,and extraction of metals.

Effect of Y and Ce on the microstructure, mechanical properties and anisotropy of as-rolled Mg-8Li-1Al alloy

The effects of combined addition of Y and Ce on the microstructure,mechanical properties and anisotropy of as-rolled Mg-8 Li-1 Al(LA81)alloy were studied.The combined addition of Y and Ce improves the mechanical properties with a low plasticity loss by solution strengthening,dispersion strengthening,grain refinement strengthening.Mg-8 Li-1 Al-0.6 Y-0.6 Ce(LA81-0.6 Y-0.6 Ce)has better mechanical properties and shows an almost isotropy.It possesses an ultimate tensile strength of 278.7 MPa and an elongation of 15.0%.Compared to LA81 alloy,the ultimate tensile strength increases by about 17.6%with an elongation reduction of only 3.5%,and a good isotropy of ultimate tensile strength and elongation(the value of ravg is near 1).

Enhanced Electromagnetic Interference Shielding in a Duplex-Phase Mg-9Li-3Al-1Zn Alloy Processed by Accumulative Roll Bonding

High electromagnetic shielding performance was achieved in the Mg-9Li-3Al-1Zn alloy processed by accumulative roll bonding(ARB).The microstructure,electromagnetic interference shielding effectiveness(SE) in the frequency of 30-1500 MHz and mechanical properties of the alloy were investigated.A model based on the shielding of the electromagnetic plane wave was used to theoretically discuss the EMI shielding mechanisms of ARB-processed alloy.Results indicate that the SE of the material increases gradually with the increase in the ARB pass.The enhanced SE can be attributed to the obvious microstructure orientation caused by ARB,and the alternative arrangement of alpha(Mg) phase and beta(Li)phase.In addition,with the increase in ARB pass,the number of interfaces between layers increases and the grain orientation of each layer tends to alignment along c-axis,which is beneficial to the reflection loss and multiple reflection loss of the incident electromagnetic wave.

Electrochemical behavior of Dy(Ⅲ) on bismuth film electrode in eutectic LiCl-KCl melts

An electrochemical study of dysprosium（III） on Bi film electrode was carried out in eutectic LiCl-KCI melts by transient and steady state electrochemical techniques.The results of transient electrochemical techniques showed that the reduction of Dy（III） appears at a more positive value than the one detected on W electrode owing to the formation of Bi-Dy intermetallic compounds through electrochemical deposition of Dy on bismuth film electrode.The thermodynamic properties of the formation for Dy-Bi intermetallics were estimated by a steady state electrochemical method in a temperature range of 713-803 K.Furthermore,the electrochemical preparation of Bi-Dy alloys was conducted by galvanostatic electrolysis at different current intensities.The Bi-Dy alloys,characterized by scanning electron microscopy equipped with energy dispersive spectrometry and X-ray diffraction,are comprised of DyBi3/5 and DyBi phases

Electrochemical Preparation of Mg-Li-Al-Er Alloys by Co-reduction in Molten Chloride

The electrochemical behavior of Mg, Li, AI and Er were investigated by electrochemical techniques in LiCI- KCI-MgCI2-AICI3-ErCI3 melts at 823 K. The cyclic voltammetry and chronopotentiometry indicated that the co-reduction of Mg, Li, AI and Er occurs at current densities more negative than -0.89 A.cm-2. Er（lll） under-potential deposited on pre-reduced AI electrode formed AI-RE alloys. X-ray diffraction （XRD） results indicated that Mg17Al12, Al2Er, Al2Er3 and Al4Li9 phases were prepared by galvanostatic electrolysis. ICP analyses of samples showed that lithium and aluminum contents of Mg-Li-AI-Er alloys could be controlled by concentration of AICI3 and cathodic current density.

Microstructure and mechanical properties of Mg-5Li-1Al sheets prepared by accumulative roll bonding

Ultrafine-grain and high-strength Mg-SLi-1Al sheets were prepared by accumulative roll bonding （ARB） process. Evolution of microstructure and mechanical properties of ARB-processed Mg-5Li-1Al sheets was investigated. Results show that, during ARB process, the evolution of deformation mechanism oft Mg-5Li-1Al alloy is as follows： twinning deformation, shear deformation, forming macro shear zone, and finally dynamic recrystallization （DRX）. The grain refining mechanism changes from twin DRX to rotation DRX. With the increase in ARB cycles, strength of the Mg-5Li-1Al sheets is enhanced, whilst elongation varies slightly. With the increase in rolling cycles, anisotropy of mechanical properties decreases. It is conclusive that strain hardening and grain refinement dominate the strengthening mechanism of Mg-5Li-1Al alloy.

Preparation of ternary Mg-Li-Sn alloys from molten salt by electrolysis

Electrochemical behavior of Mg, Li and Sn on tungsten electrodes in LiC1-KC1-MgCI2- SnC12 melts at 873 K was investigated. Cyclic voltammograms （CVs） showed that the underpotential deposition （UPD） of magnesium on pre-deposited tin leads to the formation of a Mg-Sn alloy, and the succeeding underpotential deposition of lithium on pre-deposited Mg-Sn alloy leads to the formation of a Mg-Li-Sn alloy. Chronopo- tentiometric measurements indicated that the codepositon of Mg, Li and Sn occurs at current densities more negative than -1.16 A.cm-~. X-ray diffraction （XRD） in- dicated that Mg2Sn phase is formed via galvanostatic electrolysis. The element Mg distributes homogeneously and Sn locates mainly on the grain boundaries in the Mg- Li-Sn alloy.