Growth of V2O5 nanorods from ball-milled powders and their performance in cathodes and anodes of lithium-ion batteries

Thermolysis-Driven Growth of Vanadium Oxide Nanostructures Revealed by In Situ Transmission Electron Microscopy: Implications for Battery Applications

Understanding the growth modes of 2D transition-metal oxides through direct observation is of vital importance to tailor these materials to desired structures. Here, we demonstrate thermolysis-driven growth of 2D V₂O₅ nanostructures via in situ transmission electron microscopy (TEM). Various growth stages in the formation of 2D V₂O₅ nanostructures through thermal decomposition of a single solid-state NH₄VO₃ precursor are unveiled during the in situ TEM heating. Growth of orthorhombic V₂O₅ 2D nanosheets and 1D nanobelts is observed in real time. The associated temperature ranges in thermolysis-driven growth of V₂O₅ nanostructures are optimized through in situ and ex situ heating. Also, the phase transformation of V₂O₅ to VO₂ was revealed in real time by in situ TEM heating. The in situ thermolysis results were reproduced using ex situ heating, which offers opportunities for upscaling the growth of vanadium oxide-based materials. Our findings offer effective, general, and simple pathways to produce versatile 2D V₂O₅ nanostructures for a range of battery applications.

Electrostatic Shielding Guides Lateral Deposition for Stable Interphase toward Reversible Magnesium Metal Anodes

Compared with lithium, magnesium shows a low propensity toward dendritic deposition due to its low surface self-diffusion barriers. However, due to the intrinsic surface roughness of the metal and the nonuniformity of the formed solid-electrolyte interphase, uneven deposition of Mg still happens, which brings about high local current density and continuous proliferation of the interphase, greatly exacerbating the passivation. Unfortunately, little attention has been paid to the deposition uniformity and the interfacial stability of Mg metal anodes, which result in a potential penalty. Herein, we modify the electrolyte with cathodically stable cations to guide smooth deposition via an electrostatic shielding strategy. The cations adsorbed on the initial protuberances effectively homogenize the charge flux by repulsing the incoming Mg²⁺ away from the tips. Importantly, we prove the lateral growth can benefit the interphase stability and electrochemical reversibility.

V2O5-Based nanomaterials: synthesis and their applications

Comprehensive depiction the phase-pure V₂O₅ with unique 1D, 2D, and 3D nanostructures. Illustrate the development of carbonaceous materials into the V₂O₅ electrodes. Introduce the cation doped V₂O₅ samples as the cathode material.

MoV2O8 nanostructures: controlled synthesis and lithium storage mechanism

A facile two-step strategy involving a solvothermal method and a subsequent calcining treatment was successfully developed for the preparation of MoV2O8 nanorods in the absence of any surfactants. Acetic acid was chosen as the solvent to provide an acidic environment. The as-synthesized MoV2O8 nanorods were evaluated as an anode material in lithium ion batteries, which showed excellent lithium storage performance in terms of its specific capacity, rate performance, and cycling stability. It could deliver a specific capacity of over 1325 mA h g(-1) after 50 cycles at 0.2 A g(-1), which is much higher than that of bulk MoV2O8 (617 mA h g(-1)). When the cell was cycled at a current density as high as 10.0 A g(-1), it still maintained a high specific capacity of around 570 mA h g(-1). The phase transformation, intercalation-deintercalation and partial redox processes are responsible for the lithium storage mechanism of MoV2O8 based on ex situ X-ray diffraction, X-ray photo electron spectroscopy and transmission electron microscopy studies, highlighting a new lithium storage mechanism for ternary metal oxides.

Facile synthesis of a nickel vanadate/Ni composite and its electrochemical performance as an anode for lithium ion batteries

Ni₃V₂O₈/Ni composites are synthesized by a simple hydrothermal route, and show high-rate capability and outstanding long-life cycling stability as a new anode material for Li-ion batteries.

Carbon nanotube-penetrated mesoporous V2O5 microspheres as high-performance cathode materials for lithium-ion batteries

A three-dimensional nanoarchitecture consisting of mesoporous V₂O₅ and penetrating CNTs was synthesized for high-performance lithium-ion batteries.

Improved elevated temperature performance of Al-intercalated V(2)O(5) electrospun nanofibers for lithium-ion batteries

Al-inserted vanadium pentoxide (V2O5) nanofibers (Al-VNF) are synthesized by simple electrospinning technique. Powder X-ray diffraction (XRD) patterns confirm the formation of phase-pure structure. Elemental mapping and XPS studies are used to confirm chemical insertion of Al in VNF. Surface morphological features of as-spun and sintered fibers with Al-insertion are investigated by field-emission scanning electron microscopy (FE-SEM). Electrochemical Li-insertion behavior of Al-VNFs are explored as cathode in half-cell configuration (vs. Li) using cyclic voltammetry and galvanostatic charge-discharge studies. Al-VNF (Al0.5V2O5) shows an initial discharge capacity of ∼250 mA h g(-1) and improved capacity retention of >60% after 50 cycles at 0.1 C rate, whereas native VNF showed only ∼40% capacity retention at room temperature. Enhanced high current rate and elevated temperature performance of Al-VNF (Al1.0V2O5) is observed with improved capacity retention (∼70%) characteristics. Improved performance of Al-inserted VNF is mainly attributed to the retention of fibrous morphology, apart from structural stabilization during electrochemical cycling.