Hydrogenated V₂O₅ Nanosheets for Superior Lithium Storage Properties

Abstract

V2O5 is a promising cathode material for lithium ion batteries boasting a large energy density due to its high capacity as well as abundant source and low cost. However, the poor chemical diffusion of Li+, low conductivity, and poor cycling stability limit its practical application. Herein, oxygen‐deficient V2O5 nanosheets prepared by hydrogenation at 200 °C with superior lithium storage properties are described. The hydrogenated V2O5 (H‐V2O5) nanosheets deliver an initial discharge capacity as high as 259 mAh g−1 and it remains 55% when the current density is increased 20 times from 0.1 to 2 A g−1. The H‐V2O5 electrode has excellent cycling stability with only 0.05% capacity decay per cycle after stabilization. The effects of oxygen defects mainly at bridging O(II) sites on Li+ diffusion and overall electrochemical lithium storage performance are revealed. The results reveal here a simple and effective strategy to improve the capacity, rate capability, and cycling stability of V2O5 materials which have large potential in energy storage and conversion applications.

Vanadium carbide nanoparticles encapsulated in graphitic carbon network nanosheets: A high-efficiency electrocatalyst for hydrogen evolution reaction

“…The V 2 O 5 nanosheets were synthesized by the procedures described in our previous paper [30]. In brief, 2 mmol of NH 4 VO 3 powders (Sigma-Aldrich) were mixed with 39 mL of deionized water (DW) under stirring and 1 mL of concentrated HCl (SigmaAldrich, Z37%) was added to the mixture dropwise and stirred for 30 min before transferring to 50 mL Teflon-line autoclave.…”

“…Low-temperature MTR is frequently utilized to synthesize carbides (especially SiC) without involving high temperature and costly carbonaceous gases [27,28]. Moreover, in MTR, carbides converted from the corresponding oxides retain the structural regularity [29] and V 2 O 5 nanosheets have been prepared by the traditional hydrothermal reaction [30]. During the MTR process, Mg is incorporated into V 2 O 5 which is reduced to highly active metallic vanadium while CO 2 , the thermic decomposed product of NaHCO 3 , is converted to carbon.…”

Enhancement of Electrochemical Performance by the Oxygen Vacancies in Hematite as Anode Material for Lithium-Ion Batteries

“…The half cells cycled at 30 C can still deliver a capacity of more than 40 mAh g −1 [21]. V 2 O 5 nanosheets with oxygen vacancies were also prepared by a hydrothermal reaction [22]. The as-prepared H-V 2 O 5 electrode exhibits excellent cycling stability and improved rate capability, which could be mainly attributed to the introduction of oxygen vacancies.…”

Vanadium-oxide-based electrode materials for Li-ion batteries

“…[109,121,132,133] Inspired by the exfoliation of layered graphite into graphene, the nanosheets of metal oxides might also be obtained from the peeling-off of a bulk crystal with a layered structure. Wang et al successfully synthesized V2O5 nanosheets from the exfoliation of layered V2O5 bulk crystals by a dissolution-splitting method.…”

“…[109,132,139,141,224] As a typical intercalation compound, V2O5 can exhibit a theoretical specific capacity of 440 mA h g −1…”