Pseudohexagonal Nb₂O₅ Anodes for Fast-Charging Potassium-Ion Batteries

Abstract

High-rate batteries will play a vital role in future energy storage systems, yet while good progress is being made in the development of high-rate lithium-ion batteries, there is less progress with post-lithium-ion chemistry. In this study, we demonstrate that pseudohexagonal Nb 2 O 5 (TT-Nb 2 O 5 ) can offer a high specific capacity (179 mAh g −1 ∼ 0.3C), good lifetime, and an excellent rate performance (72 mAh g −1 at ∼15C) in potassium-ion batteries (KIBs), when it is composited with a highly conductive carbon framework; this is the first reported investigation of TT-Nb 2 O 5 for KIBs. Specifically, multiwalled carbon nanotubes are strongly tethered to Nb 2 O 5 via glucose-derived carbon (Nb 2 O 5 @CNT) by a one-step hydrothermal method, which results in highly conductive and porous needle-like structures. This work therefore offers a route for the scalable production of a viable KIB anode material and hence improves the feasibility of fast-charging KIBs for future applications.

Diverse Morphologies of Nb2O5 Nanomaterials: A Comparative Study for the Growth Optimization of Elongated Spiky Nb2O5 and Carbon Nanosphere Composite

“…[40,48] The O-1s spectra are deconvoluted into four peaks, at ≈530.1, ≈531.4, ≈532.5, and ≈533.9 eV, corresponding to the Nb 2 O 5 , C─O, ─OH, and surface adsorbed water molecules, respectively (Figure S18b, Supporting Information). [17,18,23,45] These results demonstrate that the synthesized suNb 2 O 5 -CNS is well-prepared as a composite nanomaterial without its morphology and integrity demise.…”

“…00-028-0317) and are concurrent with the earlier reports. [12,23,27] Mainly, in the case of the elongated spiky sea-urchin morphologies, a highintensity and sharp peak was observed at ≈22.8°, corresponding to the (001) plane along with the broad low-intensity peak at ≈28°, relating to the (100) planes. [12,23,27] The relative intensities of the diffraction peaks observed for the small spike and elongated spiky morphologies are different and might be attributed to the preferred growth of the spikes along specific directions.…”

“…[12,23,27] Mainly, in the case of the elongated spiky sea-urchin morphologies, a highintensity and sharp peak was observed at ≈22.8°, corresponding to the (001) plane along with the broad low-intensity peak at ≈28°, relating to the (100) planes. [12,23,27] The relative intensities of the diffraction peaks observed for the small spike and elongated spiky morphologies are different and might be attributed to the preferred growth of the spikes along specific directions. The more intense diffraction peaks, i.e., [001] planes noticed in contrast to those from the [100] planes, support that the spikes tended to grow along the [001] direction.…”

“…Only a few reports on synthesizing a pseudohexagonal phase of Nb 2 O 5 are available, and it can easily be prepared at lower temperatures. [12,23] The controlled growth with desired morphologies and composites is quite a challenge, and efforts to formulate a simple and efficient approach for producing Nb 2 O 5 nanostructures with defined morphologies are significant.…”

Antimony Sulfide-Based Materials for Electrochemical Energy Conversion and Storage: Advances, Challenges, and Prospects

“…Properties containing large lattice spacing (3.93 Å), affluent redox chemistry, and low volume expansion (less than 5%) rendered Nb 2 O 5 an attractive anode material for energy-storage systems. − Based on these aforementioned advantages, the constructions of Nb 2 O 5 /Sb 2 S 3 composites would be feasible strategies to obtain novel high-performance electrodes, accompanied by high-efficiency K + /electron diffusion, enhanced electrochemical reversibility, and compact SEI films. − For Sb 2 S 3 -C@Nb 2 O 5 -C nanofibers, outstanding rate properties (148.2 mAh g –1 at 2 A g –1 ) and sustainable capacity (capacity degradation rate of 0.03% per cycle for 2200 cycles) could be found as shown in Figure d–f . In addition, as displayed in Figure g and h, Sb 2 S 3 nanoflowers were tightly anchored on 2D Ti 3 C 2 sheets, while showing strong covalent coupling, leading to remarkable cycling stability (286 mAh g –1 at 0.1 A g –1 after 500 cycles) .…”