Nickel selenides have been studied as potential anode materials for sodium-ion batteries due to their high theoretical ***,the low electrical conductivity and the large volumetric variation during the charging/dischar...
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Nickel selenides have been studied as potential anode materials for sodium-ion batteries due to their high theoretical ***,the low electrical conductivity and the large volumetric variation during the charging/discharging process greatly reduce the specific capacity and cycling lifespan of the *** this paper,a simple strategy to fabricate NiSe nanoparticles enclosed in carbon hollow nanofibers(NiSe/C@CNF)is proposed,involving the preparation of Ni-precursor nanofibers by electrospinning,the coating of polydopamine and the formation of NiSe/C@CNF by calcination and *** combination of NiSe nanoparticles and porous carbon hollow nanofibers creates a strong conductive environment,which enhances the dynamic ability of sodium-ion transport and improves charge storage *** fabricated NiSe/C@CNF material exhibits excellent *** demonstrates a high rate capability,with specific capacities of 406.8 and 300.1 mAh·g^(-1)at 0.1 and 5.0 A·g^(-1),*** results highlight the potential of NiSe/C@CNF as an anode material for sodium-ion batteries,offering a large capacity and long life.
In the process of spraying coating perovskite films,the"coffee ring"effect(CRE)leads to the problem of excessive organic ammonium salt accumulation in local areas that cannot be completely *** introduce an i...
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In the process of spraying coating perovskite films,the"coffee ring"effect(CRE)leads to the problem of excessive organic ammonium salt accumulation in local areas that cannot be completely *** introduce an in-situ targeted defect-healing strategy by incorporating butylamine formate(BAFa)ionic liquid into the spray *** liquids,due to their long carbon chain structure,tend to target flow towards the CRE region during the droplet evaporation *** coordination between the lone pair electrons in the C=O group of BAFa and Pb^(2+)effectively reduces defects in perovskite and suppresses non-radiative recombination ***,amine ligands,which are repelled to the film surface and grain boundaries,form a thin insulating monolayer in the CRE areas,forcing charge carriers to transport through areas of the perovskite with fewer *** approach enables the crystallization control and defect-heal over the Cs_(0.19)FA_(0.81)PbI_(3-x-y)Br_(x)Cl_(y)perovskite ***,the champion perovskite solar cell achieved a power conversion efficiency of 22.04%,while mini-modules with an effective area of 64.8 cm^(2)reached a peak power conversion efficiency of 18.35%,demonstrating the significant potential for commercializing large-area perovskite solar cells.
Most oxygen evolution reaction(OER)electrocatalysts show poor stability under industrial alkaline conditions(20–30 wt.%KOH).Therefore,it is essential to develop stable,efficient,and low-cost OER catalysts for industr...
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Most oxygen evolution reaction(OER)electrocatalysts show poor stability under industrial alkaline conditions(20–30 wt.%KOH).Therefore,it is essential to develop stable,efficient,and low-cost OER catalysts for industrial water ***,we present a straightforward approach for the complete electrochemical reconstruction of Ni-BDC,a Ni-based metal-organic framework,for *** method involves the continuous release of Fe^(3+)from Fe foam counter electrode in a high-concentration(6.0 M,25 wt.%)KOH *** continuously Fe^(3+)releasing not only realizes in situ Fe^(3+)doping,but also introduces abundant defects in the obtained catalyst during cyclic voltammetry activation,thereby accelerating the electrochemical *** reconstructed OER catalyst(Fe-doped nickel hydroxide/oxyhydroxide nanosheets supported on Ni foam,Fe-NiO_(x)(OH)y/NF)manifests a low overpotential of 217 mV at 10 mA cm^(-2)and 263 m V at 100 m A cm^(-2)in 1.0 M ***,the Fe-NiO_(x)(OH)_(y)/NF also demonstrates high stability in 30 wt.%*** strategy of regulating the electrochemical reconstruction process sheds light on the construction of stable and efficient OER catalysts for industrial water electrolysis.
Vanadium pentoxide(V_(2)O_(5))with a layered structure is of great interest in the field of electrochromic(EC)due to its abundance of color ***,there are still a series of problems such as slow ion diffusion,poor elec...
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Vanadium pentoxide(V_(2)O_(5))with a layered structure is of great interest in the field of electrochromic(EC)due to its abundance of color ***,there are still a series of problems such as slow ion diffusion,poor electronic conductivity and cyclic stability in the reaction ***,we successfully prepared a stable and fast multi-color electrochromic material V_(2)O_(5)-PEDOT by a simple“one-pot”*** layer space of V_(2)O_(5)could be tuned by 3,4-ethylenedioxythiophene(named V_(2)O_(5)-PEDOT)during the dissolution and recrystallization of vanadium *** expanded layer spacing facilitates rapid ion insertion and *** serves as an internal conductive pillar to improve the overall conductivity of the *** obtained intercrossing structure of the nanobelts shortens the ion diffusion distance and ensures electrolyte *** V_(2)O_(5)-PEDOT exhibits the fast response time(1.1 s for coloration and 3.5 s for bleaching at 422 nm),high optical contrast(ΔT=45%at 422 nm andΔT=35.2%at 1000 nm),great coloration efficiency(CE=97.1 cm2/C),and high cyclic stability(86%preserved after 3000 cycles).The electrochromic devices(ECD)were successfully assembled by using V_(2)O_(5)-PEDOT films as ion storage layers and electrochromic layers,demonstrating remarkable performance.
Manganese-based cathode materials are considered as a promising candidate for rechargeable aqueous zinc-ion batteries(ZIBs).Suffering from poor conductive and limited structure tolerance,various carbon matrix,especial...
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Manganese-based cathode materials are considered as a promising candidate for rechargeable aqueous zinc-ion batteries(ZIBs).Suffering from poor conductive and limited structure tolerance,various carbon matrix,especially N-doped carbon,were employed to incorporate with MnO_(2)for greatly promoted electrochemical ***,the related underlying mechanism is still unknown,which is unfavorable to guide the design of high performance ***,by incorporating layered MnO_(2)with N-doped carbon nanowires,a free-standing cathode with hierarchical core-shell structure(denoted as MnO_(2)@NC)is *** from the N-doped carbon and rational architecture,the MnO_(2)@NC electrode shows an enhanced specific capacity(325 mAh g^(−1)at 0.1 A g^(−1))and rate performance(90 mAh g^(−1)at 2 A g^(−1)),as well as improved cycling ***,the performance improvement mechanism of MnO_(2)incorporated by N-doped carbon is investigated by X-ray photoelectron spectroscopy(XPS),Raman spectrums and density functional theory(DFT)*** N atom elongates the Mn-O bond and reduces the valence of Mn^(4+)ion in MnO_(2)crystal by delocalizing its electron ***,the electrostatic repulsion will be weakened when Zn^(2+)/H^(+)insert into the host MnO_(2)lattices,which is profitable to more cation insertion and faster ion transfer kinetics for higher capacity and rate *** work elucidates a fundamental understanding of the functions of N-doped carbon in composite materials and shed light on a practical pathway to optimize other electrode materials.
A novel in-situ reactive approach based on the reactions among TiN,aluminum and boron has been developed to synthesize TiB_(2)-based composites including TiB_(2)-h BN(TB)and TiB_(2)-h BN-AlN(TBA).Fully dense ceramics ...
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A novel in-situ reactive approach based on the reactions among TiN,aluminum and boron has been developed to synthesize TiB_(2)-based composites including TiB_(2)-h BN(TB)and TiB_(2)-h BN-AlN(TBA).Fully dense ceramics with fine-grained microstructure were successfully obtained via spark plasma sintering at 1850℃/60 MPa/5 *** analysis suggests h BN flakes were homogenously distributed in the TiB_(2)*** AlN,however,they were elongated into plate-like grains during sintering,in which lots of defects in terms of stacking faults and twinning structures were *** mechanical and thermophysical properties of as-sintered ceramics were comprehensively investigated and ***-corporating AlN significantly improved the flexure strength,hardness,fracture toughness and thermal conductivity of TiB_(2)-h BN *** electrical conductivity of TB(3.06×10^(6)S/m)is larger than that of TBA(2.35×10^(6)S/m)at room temperature,but the value(6×10^(5)S/m)was lower than that of TBA(6.9×10^(5)S/m)at 1173 *** on the measurement of electrical and thermal conductivity,electron and phonon contributions to thermal conductivities of TB and TBA were calculated and their temperature dependences were illustrated.
The polymer-based solid-state electrolytes (PSEs) are promising for solid-state batteries but they have deficiencies such as low ionic conductivity, low lithium-ion transference number, and unstable electrode/electrol...
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The polymer-based solid-state electrolytes (PSEs) are promising for solid-state batteries but they have deficiencies such as low ionic conductivity, low lithium-ion transference number, and unstable electrode/electrolyte interface. Herein, we designed a hydroxyapatite nanowire doped with high-valence cations in anticipation of the formation of positively charged active sites on the nanowire surface. The higher surface activity can reduce the reaction activation energy on the nanowire surface and adsorb the anions in the PSEs as a way to improve the ionic conductivity and Li+ transference number of the PSEs. The active sites on the surface of the nanowires anchor the anions, thus increasing the Li+ transference number to 0.38, which effectively improves the ionic conductivity of the PSE to 1.58 × 10-4 S cm-1 at room temperature. At the same time, the composite polymer electrolyte has a wide electrochemical window. The lithium symmetric cell stably cycles for 800 h at a current density of 0.1 mA cm-2, and the LiFePO4||Li full cell steadily cycles for 180 cycles at a rate of 0.5 C with a capacity retention of 94.2 %. The ion doping strategy to change the surface electrical behavior of nanowires provides an idea to improve the ionic conductivity of solid-state electrolytes.
Additive manufacturing(AM),also called three-dimensional(3D)printing,offers disruptive design freedom and manufacturing flexibility due to the layer-wise incremental formation manner of *** in AM techniques provide un...
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Additive manufacturing(AM),also called three-dimensional(3D)printing,offers disruptive design freedom and manufacturing flexibility due to the layer-wise incremental formation manner of *** in AM techniques provide unique advantages and feasibilities for overcoming challenges arising from fabricating parts with complexities in geometry,materials,and properties.
Constructing a functional hybrid coating appears to be a promising strategy for addressing the poor corrosion resistance and insufficient endothelialization of Mg-based ***,the steps for preparing composite coatings a...
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Constructing a functional hybrid coating appears to be a promising strategy for addressing the poor corrosion resistance and insufficient endothelialization of Mg-based ***,the steps for preparing composite coatings are usually complicated and ***,a novel composite coating,composed of bioactive magnesium thioctic acid(MTA)layer formed by deposition and corrosion-resistant magnesium hydroxide(Mg(OH)_(2))layer grown in situ,is simply fabricated on ZE21B alloys via one-step *** electron microscopy(SEM)shows that the electrodeposited coating has a compact and uniform *** the high adhesion of the MTA/Mg(OH)_(2)hybrid coating is also confirmed by the micro-scratch *** test,scanning kelvin probe(SKP),and hydrogen evolution measurement indicate that the hybrid coating effectively reduces the degradation rate of Mg *** experiment and cell culture trial detect that the composite coating is of fine ***,the preparation mechanism of MTA/Mg(OH)_(2)hybrid coatings is discussed and *** coating shows a great potential application for cardiovascular stents.
Attributing to the high specific capacity and low electrochemical reduction potential,lithium(Li)metal is regarded as the most promising anode for high-energy Li ***,the growth of lithium dendrites and huge volume cha...
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Attributing to the high specific capacity and low electrochemical reduction potential,lithium(Li)metal is regarded as the most promising anode for high-energy Li ***,the growth of lithium dendrites and huge volume change seriously limit the development of lithium metal *** overcome these challenges,an ordered mesoporous N-doped carbon with lithiophilic single atoms is proposed to induce uniform nucleation and deposition of Li *** from the synergistic effects of interconnected three-dimensional ordered mesoporous structures and abundant lithiophilic single-atom sites,regulated local current density and rapid mass transfer can be achieved,leading to the uniform Li deposition with inhibition of dendrites and buffered volume *** a result,the as-fabricated anode exhibits a high CE of 99.8%for 200 cycles.A stable voltage hysteresis of 14 mV at 5 mA cm^(−2)could be maintained for more than 1330 h in the symmetric ***,the full cell coupled with commercial LiFePO_(4)exhibits high reversible capacity of 108 mAh g^(−1)and average Coulombic efficiency of 99.8%from 5th to 350th cycles at 1 *** ordered mesoporous carbon host with abundant lithiophilic single-atom sites delivers new inspirations into rational design of high-performance Li metal anodes.
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