Study on the structural phase transitions in NaSICON-type compounds using Ag3Sc2(PO4)3 as a model system

NaSICON (Na Super-Ionic CONducting) structured materials are among the most promising solid electrolytes for Li-ion batteries and `beyond Li-ion' batteries (e.g. Na and K) due to their superior ionic conductivities. Although this material has been well known for decades, its exact phase behaviour is still poorly understood. Herein, a starting material of Na3Sc2(PO4)3 single crystals is used, grown by flux methodology, where Na is subsequently chemically replaced by Ag, in order to take advantage of the higher scattering contrast of Ag. It is found that the NaSICON-type compound shows two phase transitions from a low-temperature monoclinic α-phase to a monoclinic β-phase at about 180 K and to a rhombohedral γ-phase at about 290 K. The framework of [Sc2(PO4)3]3− is rigid and does not change significantly with temperature and change of symmetry. The main driving force for the phase transitions is related to order–disorder phenomena of the conducting cations. The sensitivity of the phase behaviour on the ordering of these ions suggests that small compositional changes can have a great impact on the phase behaviour and, hence, on the ionic conductivity of NaSICON-structured materials.

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Fe–Si networks and charge/discharge-induced phase transitions in Li2FeSiO4 cathode materials

Physical Chemistry Chemical Physics ◽

10.1039/c8cp01962b ◽

2018 ◽

Vol 20 (21) ◽

pp. 14557-14563 ◽

Cited By ~ 6

Author(s):

Xiaobao Lv ◽

Xin Zhao ◽

Shunqing Wu ◽

Manh Cuong Nguyen ◽

Zizhong Zhu ◽

...

Keyword(s):

Phase Transitions ◽

Cathode Materials ◽

Electrode Materials ◽

Structural Phase ◽

Li Ion Batteries ◽

Structural Phase Transitions ◽

Li Ion ◽

Charge Discharge

Structural phase transitions of electrode materials are responsible for poor reversibility during charge/discharge cycling in Li-ion batteries.

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NASICON LiM2(PO4)3 electrolyte (M = Zr) and electrode (M = Ti) materials for all solid-state Li-ion batteries with high total conductivity and low interfacial resistance

Journal of Materials Chemistry A ◽

10.1039/c7ta08715b ◽

2018 ◽

Vol 6 (13) ◽

pp. 5296-5303 ◽

Cited By ~ 28

Author(s):

Hany El-Shinawi ◽

Anna Regoutz ◽

David J. Payne ◽

Edmund J. Cussen ◽

Serena A. Corr

Keyword(s):

Solid State ◽

Ionic Conductivities ◽

Total Conductivity ◽

Li Ion Batteries ◽

Interfacial Resistance ◽

Nasicon Type ◽

Solid State Batteries ◽

Li Ion ◽

All Solid State Batteries

All solid-state batteries based on NASICON-type LiM2(PO4)3 electrolyte phases are highly promising owing to their high ionic conductivities and chemical stabilities.

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Investigating the Factors Affecting the Ionic Conduction in Nanoconfined NaBH4

Inorganics ◽

10.3390/inorganics9010002 ◽

2021 ◽

Vol 9 (1) ◽

pp. 2

Author(s):

Xiaoxuan Luo ◽

Aditya Rawal ◽

Kondo-Francois Aguey-Zinsou

Keyword(s):

Ionic Conductivity ◽

Ionic Conduction ◽

Metal Hydrides ◽

Ionic Conductivities ◽

Effective Strategy ◽

Li Ion Batteries ◽

Large Cage ◽

Factors Affecting ◽

Li Ion ◽

Mcm 41

Nanoconfinement is an effective strategy to tune the properties of the metal hydrides. It has been extensively employed to modify the ionic conductivity of LiBH4 as an electrolyte for Li-ion batteries. However, the approach does not seem to be applicable to other borohydrides such as NaBH4, which is found to reach a limited improvement in ionic conductivity of 10−7 S cm−1 at 115 °C upon nanoconfinement in Mobil Composition of Matter No. 41 (MCM-41) instead of 10−8 S cm−1. In comparison, introducing large cage anions in the form of Na2B12H12 naturally formed upon the nanoconfinement of NaBH4 was found to be more effective in leading to higher ionic conductivities of 10−4 S cm−1 at 110 °C.

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Influence of thermal treatment of Ti-45Nb alloy in ultrafine-grained states on its structural parameters and heat capacity

Izvestiya vysshikh uchebnykh zavedenii. Fizika ◽

10.17223/00213411/64/9/84 ◽

2021 ◽

pp. 84-91

Author(s):

E.V. Legostaeva ◽

◽

M.A. Khimich ◽

Yu.P. Sharkeev ◽

A.Yu. Eroshenko ◽

...

Keyword(s):

Heat Treatment ◽

Heat Capacity ◽

Phase Transitions ◽

Structural Parameters ◽

Structural Phase ◽

Coherent Scattering ◽

Normal Stresses ◽

Two Phase ◽

Ω Phase ◽

Ultrafine Grained

The effect of heat treatment of the Ti-45Nb alloy in the UFG state on its structural parameters (lattice parameters, volumetric phase ratio, sizes of coherent scattering regions, residual normal stresses) and their relationship with heat capacity have been studied. It has been established that the different character of the temperature dependence of the heat capacity for the Ti-45Nb alloy in the UFG and CC states is associated with the structural-phase features of the alloy in the UFG state: the two-phase structure of a-grains and b-grains, dispersion-hardened by the ω-phase, and phase transitions in the temperature range 400-600 °С.

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Porous Al/Al2O3 two-phase nanonetwork to improve electrochemical properties of porous C/SiO2 as anode for Li-ion batteries

Electrochimica Acta ◽

10.1016/j.electacta.2019.01.121 ◽

2019 ◽

Vol 300 ◽

pp. 470-481 ◽

Cited By ~ 8

Author(s):

Jinlong Cui ◽

Jiachao Yang ◽

Jianzong Man ◽

Shaohui Li ◽

Jinpeng Yin ◽

...

Keyword(s):

Electrochemical Properties ◽

Li Ion Batteries ◽

Two Phase ◽

Li Ion

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Nasicon-Type Surface Functional Modification in Core–Shell LiNi0.5Mn0.3Co0.2O2@NaTi2(PO4)3 Cathode Enhances Its High-Voltage Cycling Stability and Rate Capacity toward Li-Ion Batteries

ACS Applied Materials & Interfaces ◽

10.1021/acsami.7b15808 ◽

2018 ◽

Vol 10 (6) ◽

pp. 5498-5510 ◽

Cited By ~ 74

Author(s):

Longwei Liang ◽

Xuan Sun ◽

Chen Wu ◽

Linrui Hou ◽

Jinfeng Sun ◽

...

Keyword(s):

High Voltage ◽

Cycling Stability ◽

Core Shell ◽

Li Ion Batteries ◽

Functional Modification ◽

Nasicon Type ◽

Rate Capacity ◽

Li Ion

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Structural phase transitions, and Br...N and Br...Br interactions in 1-phenyl-2-methyl-4-nitro-5-bromoimidazole

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768104005853 ◽

2004 ◽

Vol 60 (3) ◽

pp. 333-342 ◽

Cited By ~ 13

Author(s):

Maciej Kubicki

Keyword(s):

Phase Transitions ◽

Crystal Packing ◽

Structural Phase ◽

Molecular Geometry ◽

Second Phase ◽

Triclinic Space Group ◽

Space Group ◽

Β Phase ◽

Α Phase ◽

Second Order Transition

Crystals of C10H8N3O2Br undergo two reversible phase transitions between 295 and 100 K. The first, of an order–disorder nature, is a second-order transition and takes place continuously over a wide temperature range. This transition is connected with the doubling of the length of the c axis of the unit cell and with the change of the space group from P21/m with Z′ = 1/2 (room-temperature α-phase) to P21/c, Z′ = 1 (β-phase, 200–120 K). During this transition the molecule loses the C s symmetry of the α-phase. The second transition takes place between 118 and 115 K, and is accompanied by a change of the crystal symmetry to the triclinic space group P\bar 1 (low-temperature γ-phase). This second phase transition is accompanied by the twinning of the crystal. Neither the molecular geometry nor the crystal packing shows any dramatic changes during these phase transitions. Halogen bonds C—Br...N and dihalogen interactions Br...Br play a crucial role in determining the crystal packing and compete successfully with other kinds of weak intermolecular interactions.

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