Mg<sup>2+</sup>storage and mobility in anatase TiO<sub>2</sub>: the role of frustrated coordination

McColl, Kit; Corà, Furio

doi:10.1039/c8ta09939a

Cited by 11 publications

(6 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such frustration raises the energy of the Zn ions and lowers the activation barriers for migration compared to the most stable intercalation sites. [ 79 ] It is possible that the “split interstitial” Zn 2+ ions are mobile in the structure and can be removed upon charge via a correlated interstitialcy mechanism.…”

Section: Resultsmentioning

confidence: 99%

Multi‐Scale Investigations of δ‐Ni_0.25V₂O₅·nH₂O Cathode Materials in Aqueous Zinc‐Ion Batteries

McColl

et al. 2020

Advanced Energy Materials

Self Cite

214

142

View full text Add to dashboard Cite

devices to allow energy release at night and for continuous supply under low wind conditions. The most prevalent type of secondary energy storage uses lithiumion batteries (LIBs), that possess high energy density and long cycle life and have brought about a remarkable technical revolution for portable electronics, vehicles, and many other aspects in daily life. [1] However, considering the growing cost of the limited lithium resources and safety concerns derived from intrinsic chemical activity of metallic lithium and its combustible ester electrolytes, aqueous rechargeable batteries have been recently spotlighted as promising alternatives especially for utilization of large-scale energy storage stations. [2] Among them, aqueous zinc-ion batteries (AZIBs) have gained exceptional interest in aqueous systems due to the beneficial physicochemical properties of zinc, that is, i) a high theoretical volumetric capacity around 5585 mAh cm −3 of a metallic zinc anode compared with 2061 mAh cm −3 and 1129 mAh cm −3 for lithium and sodium anodes, respectively; ii) low redox potential of −0.762 V versus standard hydrogen electrode, and iii) electrochemical stability of metallic zinc in its sulfate solutions at near neutral or slightly acidic aqueous electrolyte providing the batteries with safe, costeffective, and environment-friendly characteristics. [3][4][5][6] Cost-effective and environmentally-friendly aqueous zinc-ion batteries (AZIBs) exhibit tremendous potential for application in grid-scale energy storage systems but are limited by suitable cathode materials. Hydrated vanadium bronzes have gained significant attention for AZIBs and can be produced with a range of different pre-intercalated ions, allowing their properties to be optimized. However, gaining a detailed understanding of the energy storage mechanisms within these cathode materials remains a great challenge due to their complex crystallographic frameworks, limiting rational design from the perspective of enhanced Zn 2+ diffusion over multiple length scales. Herein, a new class of hydrated porous δ-Ni 0.25 V 2 O 5 .nH 2 O nanoribbons for use as an AZIB cathode is reported. The cathode delivers reversibility showing 402 mAh g −1 at 0.2 A g −1 and a capacity retention of 98% over 1200 cycles at 5 A g −1 . A detailed investigation using experimental and computational approaches reveal that the host "δ" vanadate lattice has favorable Zn 2+ diffusion properties, arising from the atomic-level structure of the well-defined lattice channels. Furthermore, the microstructure of the as-prepared cathodes is examined using multi-length scale X-ray computed tomography for the first time in AZIBs and the effective diffusion coefficient is obtained by imagebased modeling, illustrating favorable porosity and satisfactory tortuosity.

show abstract

Section: Resultsmentioning

confidence: 99%

Multi‐Scale Investigations of δ‐Ni_0.25V₂O₅·nH₂O Cathode Materials in Aqueous Zinc‐Ion Batteries

McColl

et al. 2020

Advanced Energy Materials

Self Cite

214

142

View full text Add to dashboard Cite

show abstract

“…Activation barriers for ionic migration were determined using constrained geometry optimisations, with full details of the procedure described in the ESI. † 46,47 Li-orderings during intercalation were examined by considering all symmetry-inequivalent congura-…”

Section: Methodsmentioning

confidence: 99%

Fast lithium-ion conductivity in the ‘empty-perovskite’ n = 2 Ruddlesden–Popper-type oxysulphide Y₂Ti₂S₂O₅

McColl

Corà

2021

J. Mater. Chem. A

Self Cite

View full text Add to dashboard Cite

show abstract

“…Therefore, the inserted ions remain in a "frustrated" coordination and can diffuse through the structure with low energy barriers. 39,40 Bronze frameworks are therefore candidate materials for high Mg 2+ mobility electrodes. Herein, we report the electrochemical characterization of V 4 Nb 18 O 55 (which possesses a distorted T-Nb 2 O 5 structure) in Mg 2+ electrolytes.…”

Section: ■ Introductionmentioning

confidence: 99%

“…Upon Li + or Mg 2+ incorporation, the polyhedra are effectively locked in place by shared edges and cannot tilt. Therefore, the inserted ions remain in a “frustrated” coordination and can diffuse through the structure with low energy barriers. , Bronze frameworks are therefore candidate materials for high Mg 2+ mobility electrodes.…”

Section: Introductionmentioning

confidence: 99%

Probing Mg Intercalation in the Tetragonal Tungsten Bronze Framework V₄Nb₁₈O₅₅

et al. 2020

Self Cite

View full text Add to dashboard Cite

While commercial Li-ion batteries offer the highest energy densities of current rechargeable battery technologies, their energy storage limit has almost been achieved. Therefore, there is considerable interest in Mg batteries, which could offer increased energy densities compared to Li-ion batteries if a high-voltage electrode material, such as a transition metal oxide, can be developed. However, there are currently very few oxide materials which have demonstrated reversible and efficient Mg 2+ insertion and extraction at high voltages; this is thought to be due to poor Mg-ion diffusion kinetics within the oxide structural framework. Herein, the authors provide conclusive evidence of electrochemical insertion of Mg 2+ into the tetragonal tungsten bronze V4Nb18O55, with a maximum reversible electrochemical capacity of 75 mA h g −1 , which corresponds to a magnesiated composition of Mg4V4Nb18O55. Experimental electrochemical magnesiation/de-magnesiation revealed a large voltage hysteresis with charge/discharge (1.12 V vs Mg/Mg 2+ ); by limiting magnesiation to a composition of Mg2V4Nb18O55, this hysteresis can be reduced down to only 0.5 V. Hybrid-exchange Density Functional Theory (DFT) calculations suggest that a limited number of Mg sites are accessible via low-energy diffusion pathways, but that larger kinetic barriers need to be overcome to access the entire structure. The reversible Mg-ion intercalation involved concurrent V and Nb redox activity and changes in crystal structure, confirmed by an array of complimentary methods including powder X-ray diffraction, X-ray absorption spectroscopy, and energy-dispersive X-ray spectroscopy. Consequently, It can be concluded that the tetragonal tungsten bronzes show promise as intercalation electrode materials for Mg batteries. 30 the development of new energy storage technologies is par-31 amount. While Li-ion batteries have achieved great com-32 mercial success, 1 and are the most energy-dense recharge-33 able storage technology for portable applications, the tech-34 nology already heavily optimized, and future increases in35 energy density are predicted to be incremental. 2 Therefore,36 there is a need to develop new, low cost, and sustainable 37 battery chemistries for applications such as future electric 38 vehicle and grid storage. Mg metal anodes have a lower pro-39 pensity to form dendrites (that can cause cell failure) from 40 stripping and plating, which means that it could be used di-41 rectly as a metallic anode, 3-5 which would offer up to a five-42 fold increase in anodic volumetric energy density (Mg metal 43 = 3833 mA h cm −3 ) compared to Li-ion graphite anodes 44 (∼800 mA h cm −3 ), leading to an overall doubling in energy 45 density if a suitably high-energy density electrode material 46 can be found. 6 In comparison to Li + , the divalent ion Mg 2+ 47 transfers twice the charge (2 e − per Mg 2+ ion) when moving 48 between anode and cathode. This phenomenon decouples 49 the effect of electronic changes from the availability of va-50 cant sites in th...

show abstract

Mg²⁺storage and mobility in anatase TiO₂: the role of frustrated coordination

Abstract: Low migration barriers of ∼540 meV allow good Mg mobility under dilute conditions, but cooperative lattice distortions limit mobility at high Mg concentrations.

Cited by 11 publications

References 65 publications

Multi‐Scale Investigations of δ‐Ni_0.25V₂O₅·nH₂O Cathode Materials in Aqueous Zinc‐Ion Batteries

Multi‐Scale Investigations of δ‐Ni_0.25V₂O₅·nH₂O Cathode Materials in Aqueous Zinc‐Ion Batteries

Fast lithium-ion conductivity in the ‘empty-perovskite’ n = 2 Ruddlesden–Popper-type oxysulphide Y₂Ti₂S₂O₅

Probing Mg Intercalation in the Tetragonal Tungsten Bronze Framework V₄Nb₁₈O₅₅

Contact Info

Product

Resources

About

Mg2+storage and mobility in anatase TiO2: the role of frustrated coordination

Abstract: Low migration barriers of ∼540 meV allow good Mg mobility under dilute conditions, but cooperative lattice distortions limit mobility at high Mg concentrations.

Cited by 11 publications

References 65 publications

Multi‐Scale Investigations of δ‐Ni0.25V2O5·nH2O Cathode Materials in Aqueous Zinc‐Ion Batteries

Multi‐Scale Investigations of δ‐Ni0.25V2O5·nH2O Cathode Materials in Aqueous Zinc‐Ion Batteries

Fast lithium-ion conductivity in the ‘empty-perovskite’ n = 2 Ruddlesden–Popper-type oxysulphide Y2Ti2S2O5

Probing Mg Intercalation in the Tetragonal Tungsten Bronze Framework V4Nb18O55

Contact Info

Product

Resources

About

Mg²⁺storage and mobility in anatase TiO₂: the role of frustrated coordination

Multi‐Scale Investigations of δ‐Ni_0.25V₂O₅·nH₂O Cathode Materials in Aqueous Zinc‐Ion Batteries

Multi‐Scale Investigations of δ‐Ni_0.25V₂O₅·nH₂O Cathode Materials in Aqueous Zinc‐Ion Batteries

Fast lithium-ion conductivity in the ‘empty-perovskite’ n = 2 Ruddlesden–Popper-type oxysulphide Y₂Ti₂S₂O₅

Probing Mg Intercalation in the Tetragonal Tungsten Bronze Framework V₄Nb₁₈O₅₅