V₂O₃ Polycrystalline Nanorod Cathode Materials for Li‐Ion Batteries with Long Cycle Life and High Capacity Retention

Abstract

Type of publicationArticle ( Embargo information Access to this article is restricted until 12 months after publication by request of the publisher. Abstract: We report on the electrochemical performance of V2O3 polycrystalline nanorods (poly-NRs) as a cathode material for Li-ion batteries. Poly-NRs are formed via thermal treatment of V2O5 nanotubes in a N2 atmosphere. X-ray and electron diffraction are used to confirm the thermal reduction. Through galvanostatic cycling we demonstrate that poly-NRs offer excellent capacity retention over 750 cycles. The capacity retention from the 50 th to the 750 th cycle was an impressive ~ 94%, retaining a capacity of ~ 120 mAh g -1 after 750 cycles. The outstanding stability of the nanocrystal-containing V2O3 poly-NRs over many cycles demonstrates that vanadium(III) oxide (V2O3) performs very well as a cathode material. Full Li-ion cells with paired V2O3 poly-NR cathode and a pre-charged Co3O4 inverse opal conversion mode anode demonstrated high initial capacities and retained a capacity of 153 mAh g -1 after 50 cycles.The capacities achieved with our V2O3 poly-NRs/ Co3O4 IO full cells are comparable to the capacities obtained from the most commonly used cathode materials when cycled in a half cell arrangement versus pure Li metal.

Superior Sodium Storage of Carbon-Coated NaV6O15 Nanotube Cathode: Pseudocapacitance Versus Intercalation

“…This might be due to the decomposition of the intercalated amine template at high temperature. One can see that the nanoscrolls exhibit some defects compared to VO x nanotubes without calcination. − In addition, Na-VBNT displays a polycrystalline structure, which can be verified by the selected area electron diffraction (SAED) pattern (Figure d). Moreover, Na-VBNT@C morphology appears to consist of adherent clewlike spheres (Figure e), with open-ended nanotubes (Figure e,f marked with yellow arrows).…”

Emerging Layered Metallic Vanadium Disulfide for Rechargeable Metal‐Ion Batteries: Progress and Opportunities

“…According to previous investigations,t he effect of crystal structures on electrochemical performance can primarily be divided into fivea spects:c rystallinity, [162][163][164] orientation, [165] layer structure (number and interlayer spacing), [146,[166][167][168] lattice defects, [169,170] and phase types. [171][172][173] Interestingly,i th as also been reported that ac rystal structure (high crystallinity) with a periodic lattice and ordered arrangement of atoms, [174][175][176][177][178][179][180] and an amorphous (low crystallinity)s tructure with abundant po-tential active sites on the surface/interface ands mall specific mass, [181][182][183][184][185][186][187] can enhancet he electrochemical performance, to ac ertain degree, which causes great confusion to researchers. It is thus highly desirable to summarize and clarify the effect of the crystallinity of the structure on the electrochemical performance of VS 2 .…”

NaV2O5 from Sodium Ion-Exchanged Vanadium Oxide Nanotubes and Its Efficient Reversible Lithiation as a Li-Ion Anode Material

“…11 While as-made VONTs exhibit poor electrochemical performance they are quite useful as a starting structure to provide nanorod or nanowire-type structures with nanoscale features after various post-treatments. [12][13] The motivating reason to utilize this ion-accessible nanotube structure was to create NaV 2 O 5 that is both efficient and stable as a Li-ion battery anode at low voltages, using ion-exchange protocols. Oxides are essentially much denser than graphite, and consequently could increase the volumetric energy density if the stable intercalation processes is efficient and reversible at low…”

“…Vanadium oxide nanotubes (VONTs) were first reported in 1998 by Spahr et al and since then has been a great deal of research into how to fully optimize their electrochemical performance as a cathode material for lithium ion (Li-ion) batteries and as an anode using vanadate bronzes and closely related compounds. − Typically VONTs are prepared by hydrothermal treatment of a vanadium oxide precursor mixed with a primary amine. , The amine molecules are crucial to the formation of the VONTs as they maintain the vanadium oxide layers which scroll to form the nanotube structure. , While the amines are vital in the synthesis of the VONTs, they are unfortunately detrimental to their electrochemical performance. , It has been proposed that the amine molecules occupy the majority of the possible lithium intercalation sites within the VONTs and hence are responsible for the poor cycling performance which has been reported for as-synthesized VONTs . While as-made VONTs exhibit poor electrochemical performance, they are quite useful as a starting structure to provide nanorod or nanowire-type structures with nanoscale features after various post-treatments. , …”