Towards Understanding the Different Influences of Grain Boundaries on Ion Transport in Sulfide and Oxide Solid Electrolytes

Solid electrolytes provide a route to the development of all-solid-state batteries that can potentially surpass the safety and performance of conventional liquid electrolyte-based devices. Sulfide solid electrolytes have received particular attention as a result of their high ionic conductivities. One of the main reasons for such high ionic conductivity is the apparently reduced grain boundary resistance of sulfide solid electrolytes compared to their oxide counterparts, but this is not fully established. Using two model electrolyte systems, Na3PS4 and Na3PO4, we apply a novel microscale simulation approach to analyze ionic transport in polycrystalline materials with various grain volumes. For Na3PO4, high grain boundary resistance is found, with the Na-ion conductivity decreasing with decreasing grain volume. For Na3PS4, the overall influence of grain boundaries is significantly reduced compared to the oxide. Detailed analysis reveals a minimal change in the local structures and Na-ion conduction mechanism between bulk and polycrystalline Na3PS4, whereas the change is far more substantial for Na3PO4, with evidence of over-coordination of Na ions at the grain boundaries. Our microscale approach helps to explain the fundamentally different influences of grain boundaries on ion transport in phosphate and thiophosphate solid electrolytes.

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Elucidating the nature of grain boundary resistance in lithium lanthanum titanate

Journal of Materials Chemistry A ◽

10.1039/d0ta11539h ◽

2021 ◽

Author(s):

Adam R. Symington ◽

Marco Molinari ◽

James A. Dawson ◽

Joel M. Statham ◽

John Purton ◽

...

Keyword(s):

Solid State ◽

Grain Boundary ◽

Solid Electrolytes ◽

Rechargeable Batteries ◽

Boundary Resistance ◽

Lithium Lanthanum Titanate ◽

Lanthanum Titanate ◽

Solid State Batteries ◽

All Solid State Batteries ◽

And Performance

Solid electrolytes for all-solid-state batteries are generating remarkable research interest as a means to improve the safety, stability and performance of rechargeable batteries.

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Quantifying the impact of disorder on Li-ion and Na-ion transport in perovskite titanate solid electrolytes for solid-state batteries

Journal of Materials Chemistry A ◽

10.1039/d0ta05343k ◽

2020 ◽

Vol 8 (37) ◽

pp. 19603-19611

Author(s):

Adam R. Symington ◽

John Purton ◽

Joel Statham ◽

Marco Molinari ◽

M. Saiful Islam ◽

...

Keyword(s):

Solid State ◽

Ion Transport ◽

Solid Electrolytes ◽

Research Interest ◽

Considerable Research ◽

Solid State Batteries ◽

Li Ion ◽

All Solid State Batteries ◽

And Performance ◽

The Impact

Solid electrolytes for all-solid-state batteries are generating considerable research interest as a means to improving their safety, stability and performance.

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Ionic Conductivities and Microstructures of CeO2:Y203 Solid Electrolytes

MRS Proceedings ◽

10.1557/proc-548-623 ◽

1998 ◽

Vol 548 ◽

Cited By ~ 4

Author(s):

Chunyan Tian ◽

Siu-Wai Chan

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Solid Electrolytes ◽

Dopant Concentration ◽

Ionic Conductivities ◽

Oxygen Depletion ◽

Boundary Conductivity ◽

Size Dependent ◽

Impurity Segregation ◽

Microanalytical Technique

ABSTRACTIonic conductivities of solid CeO2:Y203 electrolytes were systematically investigated as a function of dopant concentration and sintering temperatures. The highest lattice conductivity occurred at 6–8% dopant concentration, and maximum grain boundary conductivity was observed at 10% dopant concentration. The sintering temperature was found to have a significant effect on the conductivities of the pellets. The samples sintered at lower temperatures (T≤140°C) showed higher grain boundary conductivity than those sintered at 150°C; this was found to be related to size-dependent-impurity segregation and precipitation at grain boundaries. The grain boundary conductivities as related to the microstructure are discussed by adopting different grain boundary models. Solute segregation and oxygen depletion at grain boundaries, which have been suggested to be responsible for the grain boundary resistivities in these samples, were examined by a microanalytical technique for small-grain-size samples.

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Theoretical and Experimental Studies of ion Transport in Mixed Polyanion Solid Electrolytes

10.21203/rs.3.rs-1102507/v1 ◽

2021 ◽

Author(s):

Zeyu Deng ◽

Tara Mishra ◽

Eunike Mahayoni ◽

Qianli Ma ◽

Olivier Guillon ◽

...

Keyword(s):

Ion Transport ◽

Transport Properties ◽

Solid Electrolytes ◽

Kinetic Monte Carlo ◽

Large Body ◽

Experimental Studies ◽

Ionic Conductivities ◽

Time Range ◽

Solid State Batteries ◽

Kinetic Monte Carlo Simulations

Abstract Lithium and sodium (Na) mixed polyanion solid electrolytes for all-solid-state batteries display some of the highest ionic conductivities reported to date. However, the effect of polyanion mixing on ion transport properties is still debated. Here, we focus on Na1+xZr2SixP3-xO12 (0 ≤ x ≤ 3) NASICON electrolyte to elucidate the role of polyanion mixing on Na-transport properties. Although there is a large body of data available on this NASICON system, transport properties extracted from experiments or theory vary by orders of magnitude, signifying the need to bridge the gap between different studies. Here, more than 2,000 distinct ab initio-based kinetic Monte Carlo simulations have been used to map the statistically vast compositional space of NASICON over an unprecedented time range and spatial resolution and across a range of temperatures. We performed impedance spectroscopy of samples with varying Na compositions revealing that the highest ionic conductivity (~ 0.1 S cm–1) is achieved in Na3.4Zr2Si2.4P0.6O12, in line with our predictions (~0.2 S cm–1). Our predictions indicate that suitably doped NASICON compositions, especially with high silicon content, can achieve high Na+ mobilities. Our findings are relevant for the optimization of mixed polyanion solid electrolytes and electrodes, including sulfide-based polyanion frameworks, which are known for their superior ionic conductivities.

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Morphology and atomic structure of segregated grain boundaries in Cu-Sb

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121673 ◽

1992 ◽

Vol 50 (1) ◽

pp. 254-255

Author(s):

R. W. Fonda ◽

D. E. Luzzi

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Intergranular Fracture ◽

Atomic Structure ◽

Copper Alloys ◽

Polycrystalline Materials ◽

Grain Boundary Embrittlement ◽

Boundary Embrittlement

The properties of polycrystalline materials are strongly dependant upon the strength of internal boundaries. Segregation of solute to the grain boundaries can adversely affect this strength. In copper alloys, segregation of either bismuth or antimony to the grain boundary will embrittle the alloy by facilitating intergranular fracture. Very small quantities of bismuth in copper have long been known to cause severe grain boundary embrittlement of the alloy. The effect of antimony is much less pronounced and is observed primarily at lower temperatures. Even though moderate amounts of antimony are fully soluble in copper, concentrations down to 0.14% can cause grain boundary embrittlement.

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Grain-boundary-resistance-less Na3SbS4-Se solid electrolytes for all-solid-state sodium batteries

Nano Energy ◽

10.1016/j.nanoen.2019.104109 ◽

2019 ◽

Vol 66 ◽

pp. 104109 ◽

Cited By ~ 9

Author(s):

Hongli Wan ◽

Jean Pierre Mwizerwa ◽

Fudong Han ◽

Wei Weng ◽

Jing Yang ◽

...

Keyword(s):

Solid State ◽

Grain Boundary ◽

Solid Electrolytes ◽

Boundary Resistance ◽

Sodium Batteries

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On determining the height of the potential barrier at grain boundaries in ion-conducting oxides

Physical Chemistry Chemical Physics ◽

10.1039/c5cp06387f ◽

2016 ◽

Vol 18 (4) ◽

pp. 3023-3031 ◽

Cited By ~ 18

Author(s):

Sangtae Kim ◽

Seong K. Kim ◽

Sergey Khodorov ◽

Joachim Maier ◽

Igor Lubomirsky

Keyword(s):

Grain Boundary ◽

Space Charge ◽

Grain Boundaries ◽

Potential Barrier ◽

Boundary Resistance ◽

Resistivity Ratio ◽

Linear Diffusion ◽

Conducting Oxides ◽

Ion Conducting

Combining the linear diffusion and resistivity ratio models, one can distinguish the grain boundary resistance related to space charge from the resistance from other sources.

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Degradation of the Strength of a Grain and a Grain Boundary due to the Accumulation of the Structural Defects of Crystal

Volume 12: Materials: Genetics to Structures ◽

10.1115/imece2018-87264 ◽

2018 ◽

Author(s):

Guoxiong Zheng ◽

Yifan Luo ◽

Hideo Miura

Keyword(s):

Thin Film ◽

Grain Boundary ◽

Tensile Test ◽

Grain Boundaries ◽

Intergranular Fracture ◽

Semiconductor Devices ◽

Ebsd Analysis ◽

Structural Defects ◽

Polycrystalline Materials ◽

Transgranular Fracture

Various brittle fractures have been found to occur at grain boundaries in polycrystalline materials. In thin film interconnections used for semiconductor devices, open failures caused by electro- and strain-induced migrations have been found to be dominated by porous random grain boundaries that consist of a lot of defects. Therefore, it is very important to explicate the dominant factors of the strength of a grain boundary in polycrystalline materials for assuring the safe and reliable operation of various products. In this study, both electron back-scatter diffraction (EBSD) analysis and a micro tensile test in a scanning electron microscope was applied to copper thin film which is used for interconnection of semiconductor devices in order to clarify the relationship between the strength and the crystallinity of a grain and a grain boundary quantitatively. Image quality (IQ) value obtained from the EBSD analysis, which indicates the average sharpness of the diffraction pattern (Kikuchi pattern) was applied to the crystallinity analysis. This IQ value indicates the total density of defects such as vacancies, dislocations, impurities, and local strain, in other words, the order of atom arrangement in the observed area in nano-scale. In the micro tensile test system, stress-strain curves of a single crystal specimen and a bicrystal specimen was measured quantitatively. Both transgranular and intergranular fracture modes were observed in the tested specimens with different IQ values. Based to the results of these experiments, it was found that there is the critical IQ value at which the fracture mode of the bicrystal specimen changes from brittle intergranular fracture at a grain boundary to ductile transgranular fracture in a grain. The strength of a grain boundary increases monotonically with IQ value because of the increase in the total number of rigid atomic bonding. On the other hand, the strength of a grain decreases monotonically with the increase of IQ value because the increase in the order of atom arrangement accelerates the movement of dislocations. Finally, it was clarified that the strength of a grain boundary and a grain changes drastically as a strong function of their crystallinity.

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