Micro-nano structured VNb9O25 anode with superior electronic conductivity for high-rate and long-lif

来源 :材料科学技术(英文版) | 被引量 : 0次 | 上传用户:ssfdlah
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
The oxygen vacancies and micro-nano structure can optimize the electron/Li+migration kinetics in anode materials for lithium batteries(LIBs).Here,porous micro-nano structured VNb9O25 composites with rich oxygen vacancies were reasonably prepared via a facile solvothermal method combined with annealing treatment at 800℃for 30 h(VNb9 O25-30 h).This micro-nano structure can enhance the contact of active material/electrolyte,and shorten the Li+diffusion distance.The introduction of oxygen vacancies can further boosts the intrinsic conductivity of VNb9O25-30 h for achieving excellent LIB performance.The as-prepared VNb9O25-30 h anode showed advanced rate capability with reversible capacity of 122.2 mA h g-1 at 4 A g-1,and delivered excellent capacity retention of~100%after 2000 cycles.Meanwhile,VNb9O25-30 h provides unexpected long-cycle life(i.e.,reversible capacity of 165.7 mA h g-1 at 1 A g-1 with a high capacity retention of 85.6%even after 8000 cycles).Additionally,coupled with the LiFePO4 cathode,the LiFePO4//VNb9O25-30 h full cell delivers superior LIB properties with high reversible capacities of 91.6 mA h g-1 at 5C for 1000 cycles.Thus,such reasonable construction method can assist in other high-performance niobium-based oxides in LIBs.
其他文献
Herein,we rationally constructed a hybrid heterostructure comprising porous g-C3N4(CN)-encapsulated anatase TiO2 hollow spheres(TOHS)via a synthesis method that involves hydrothermal and calcination treatments.The fabricated hybrid,termed CN/TOHS,demonstr
Nanocrystalline metals with high Gibbs free energy have a strong tendency towards thermally driven grain growth,thus understanding the critical size or temperature of grain growth is vital for their applications.The investigations of thermal stability wer
CeO2/g-C3N4 heterojunction photocatalyst had been successfully fabricated through a one-step in-situ pyrolysis formation of 3D hollow CeO2 mesoporous nanospheres and 2D g-C3N4 nanosheets together with simultaneous removal of carbon sphere templates after
Low ductility and strength are major bottlenecks against Mg alloys\'wide applications.In this work,we systematically design the composition and fabrication process for a low-alloyed Mg-Zn-Ca alloy,showing that it can be extruded at low temperatures(~250
Cold spraying(CS),or cold gas dynamic spray(CGDS),is an emerging solid-state powder deposition process,allowing fast and mass production and restoration of metallic components.CS of metal matrix composites(MMCs)has attracted increasing attention from acad
In this study,the carbon quantum dots,which can emit sharp red light(R-CQDs)under optical excitation,were synthesized via simple heat treatment of wine lees.The features of the photoluminescence(PL)emission from R-CQDs in solutions with different pH value
Fatigue crack growth(FCG)tests were conducted on a medium-Mn steel annealed at two intercritical annealing temperatures,resulting in different austenite(γ)to ferrite(α)phase fractions and different γ(meta-)stabilities.Novel in-situ hydrogen plasma chargin
All-inorganic halide perovskite solar cells(PSCs)have acquired great progress,especially CsPbI2Br.However,their photoelectric conversion efficiency(PCE)remains far below the theoretical predictions.Non-radiative recombination is one of the important issue
The magnetic properties,magnetocaloric effect and magnetoresistance in ErNi single crystal have been investigated in detail.With decreasing temperature,ErNi single crystal undergoes two successive mag-netic transitions:a paramagnetic to ferromagnetic tran
Taking advantage of the magnetic field inside transmission electron microscope(TEM),a unique Lorentz-force-actuated method for quantitative friction tests was developed via a commercial electromechanical holder.With this approach,a submicron-sized silver