Single crystal H-Nb₂O₅ growing along the [001] crystal direction for ultrafast lithium storage

Abstract

Single crystal H-Nb2O5 grown along the [001] crystal direction was synthesized by a simple and effective one-pot annealing process. This structure can more effectively maintain structural integrity and significantly improve Li+ diffusion kinetics.

In-Depth Investigation of the Mechanism of Dehydration-Induced Phase Transformation from Nb3O7(OH) to H-Nb2O5: A Theoretical and Experimental Approach

“…It is well-known that the monoclinic H-Nb 2 O 5 is the thermodynamically stable high temperature phase and possesses special inherent properties compared with other niobium oxide. For instance, the monoclinic H-Nb 2 O 5 has received considerable attention in lithium-ion batteries, due to its continuous and fast Li + diffusion channels parallel to b axis. − In our previous study, H-Nb 2 O 5 exhibited a higher exciton binding energy compared to T-Nb 2 O 5 and TT-Nb 2 O 5 . The H-Nb 2 O 5 with the remarkable intrinsic excitonic property will be a potentially promising optoelectronic semiconductor .…”

“…5 primitive cell, while also considering the reasonable CPU time costs. The crystalline supercell was relaxed until the total energy and force converged to within 10 −5 eV and 0.02 eV/Å, respectively.…”

“Fast-Charging” Anode Materials for Lithium-Ion Batteries from Perspective of Ion Diffusion in Crystal Structure

“…Moreover, the multielectron redox reaction causes it to express high-theoretical specific capacity, providing the opportunity for the development of high energy density and high-power density batteries. Niobium-based materials mainly include Nb 2 O 5 , Ti–Nb oxides, and Nb–W oxides . It has appeared as an attractive candidate for “fast-charging” anode materials.…”

“…For example, the synthesis of H-Nb 2 O 5 single crystals growing in the direction [001] by direct and efficient one-pot annealing in the air could not only more effectively cope with volume fluctuations and reduce side reactions with the electrolyte, but also exhibit a more efficient Li + diffusion path. Single-crystal H-Nb 2 O 5 displays ultrahigh-rate performance and long life, with a capacity of 115.6 mAh g –1 at 25 C after 3000 cycles (Figure c) . Besides, Nb 2 O 5 -δ/graphite composites are prepared through the ball milling method, and the presence of graphite in the mixture facilitates the formation of Nb 12 O 29 during the ball milling process, which restricts the particle size of the active material and ameliorates the total conductivity of the composite electrode.…”

“…(c) Schematic illustration of the synthesis process, SEM images, and cycling performance of single-crystalline H-Nb 2 O 5 . Reprinted with permission from ref . Copyright 2022 Royal Society of Chemistry.…”