Nanoscale Phase Engineering in Two-Dimensional Niobium Pentoxide Anodes toward Excellent Electrochemical Lithium Storage

Abstract

Niobium pentoxide (Nb 2 O 5 ) material is a promising anode for lithium-ion batteries (LIBs) due to the outstanding cycle performance and rate capability. However, the relatively low capacity severely limits the comprehensive performance. Generally, nanoscale engineering of the morphology and chemical composition of Nb 2 O 5 anodes is employed to improve electrochemical lithium storage. In this work, we promote the reservable capacity of a sheetlike Nb 2 O 5 anode by designing nanoscale phase interfaces between the nanodomains of T-Nb 2 O 5 , M-Nb 2 O 5 , and H-Nb 2 O 5 phases, which are generated by good control over the calcination of Nb 3 O 7 F precursor at high temperatures. Microstructural and chemical analyses show that the sample calcined at 750 °C (Nb 2 O 5 -750) has optimized structural advantages to efficiently store lithium ions. When evaluated as anodes for LIBs, the Nb 2 O 5 -750 sample shows excellent lithium storage properties. In specific, the Nb 2 O 5 -750 electrode delivers a reversible capacity of 270.4 mAh g −1 at 1C after 200 cycles. At a high rate of 5C, the Nb 2 O 5 -750 electrode has a reversible capacity of 174 mAh g −1 after 800 cycles. This work provides an alternative way to improve the ion storage in the electrodes with intrinsic polymorphic structures.

A Composite of Nb2O5 and MoO2 as a High‐Capacity High‐Rate Anode Material for Lithium‐Ion Batteries

“…Although there is a loss in capacity between 1 C and 20 C, this is in line with work by Liu et al ., one of the few studies that presented high‐rate results for a pure MoO 2 [53] . The capacities also surpass recent work reported on pure Nb 2 O 5 , [54–56] which is expected due to its lower theoretical capacity. There appears to be some polarisation at this rate, suggesting further work is needed to improve the resistance at high rates via routes such as optimisation of the slurry formulation and the electrode manufacturing route.…”

Niobium‐Based Oxide for Anode Materials for Lithium‐Ion Batteries

“…[37] Nb 2 O 5 nanosheets with thicknesses of 62,68,78 nm was prepared by hydrothermal and annealing methods by Zhang et al. [38] Among them, the capacity of the negative electrode material calcined by 750 °C was maintained at 174 mAh g-1 after 400 cycles at a current density of 5c.…”

Recent advances in in situ and operando characterization techniques for Li7La3Zr2O12-based solid-state lithium batteries

“…100 Near the interface, LLZO was converted from a cubic to tetragonal phase while interlayers such as LBO or lithiated Nb 2 O 5 minimized elemental cross-contamination and stabilized the cubic phase. 229,230 In addition to depth orientation measurement, cross-sectional ToF-SIMS mapping images of CE-based cells before and after cycling indicate that Li + preferentially migrates along the amorphous phase in the polymer matrix. 231 Furthermore, ToF-SIMS mapping images also reveal the presence of Li dendrites in LLZO ceramic pellets after cycling.…”