Towards the Digitalisation of Porous Energy Materials: Evolution of Digital Approaches for Microstructural Design

Abstract In the quest for developing novel and efficient batteries, a great interest has been raised for sustainable K-based honeycomb layer oxide materials, both for their application in energy devices as well as for their fundamental material properties. A key issue in the realization of efficient batteries based on such compounds, is to understand the K-ion diffusion mechanism. However, investigation of potassium-ion (K$$^+$$ + ) dynamics in materials using e.g. NMR and related techniques has so far been very challenging, due to its inherently weak nuclear magnetic moment, in contrast to other alkali ions such as lithium and sodium. Spin-polarised muons, having a high gyromagnetic ratio, make the muon spin rotation and relaxation ($$\mu ^+$$ μ + SR) technique ideal for probing ions dynamics in these types of energy materials. Here we present a study of the low-temperature magnetic properties as well as K$$^+$$ + dynamics in honeycomb layered oxide material $${\hbox {K}_2\hbox {Ni}_2\hbox {TeO}_6}$$ K 2 Ni 2 TeO 6 using mainly the $$\mu ^+$$ μ + SR technique. Our low-temperature $$\mu ^+$$ μ + SR results together with complementary magnetic susceptibility measurements find an antiferromagnetic transition at $$T_{\mathrm{N}}\approx 27$$ T N ≈ 27 K. Further $${\mu}^{+}$$ μ + SR studies performed at higher temperatures reveal that potassium ions (K$$^+$$ + ) become mobile above 200 K and the activation energy for the diffusion process is obtained as $$E_{\mathrm{a}}=121 (13)$$ E a = 121 ( 13 ) meV. This is the first time that K$$^+$$ + dynamics in potassium-based battery materials has been measured using $$\mu ^+$$ μ + SR. Assisted by high-resolution neutron diffraction, the temperature dependence of the K-ion self diffusion constant is also extracted. Finally our results also reveal that K-ion diffusion occurs predominantly at the surface of the powder particles. This opens future possibilities for potentially improving ion diffusion as well as K-ion battery device performance using nano-structuring and surface coatings of the particles.

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1D to 2D Na-Ion Diffusion Linked to Structural Transitions in Na0.7CoO2

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314096363 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C363-C363

Author(s):

Marisa Medarde ◽

Mattia Mena ◽

Jorge Gavilano ◽

Ekaterina Pomjakushina ◽

Jun Sugiyama ◽

...

Keyword(s):

Solid State ◽

Structural Similarity ◽

Clean Energy ◽

Rechargeable Batteries ◽

Atomic Scale ◽

Structural Transitions ◽

Ion Diffusion ◽

Energy Materials ◽

Energy Devices ◽

Neutron Powder Diffraction Data

One of the most important scientific problems faced by our society is how to convert and store clean energy. In order to achieve a significant progress in this field we need to understand the fundamental dynamical processes that govern the transfer of energy on an atomic scale. For many energy devices such as solid-state batteries and solid-oxide fuel cells, this means understanding and controlling the complex mechanisms of ion diffusion in solid matter. Because of the unusual evolution of correlated electronic properties (frustrated magnetism and superconductivity), the layered Co-oxide family NaxCoO2 (0<x<1), object of this work, has been extensively studied during the last decade. More recently it has also attracted the attention of applied sciences, mainly because of its structural similarity with LixCoO2, one of the most common Li-ion battery electrodes. In view of the larger abundance of Na in the earth crust with respect to Li, Na-ion batteries enjoy an increased attention. Hence we decided to investigate the Na-ion diffusion in this material, whose possible use as cathode for solid-state rechargeable batteries has recently been proposed [1]. The present study reports the observation of a crossover from quasi-1D to 2D Na-ion diffusion in Na0.7CoO2. High resolution neutron powder diffraction data indicate the existence of two structural transitions at T1=290K and T2=400K [2]. We present here evidence indicating that both transitions are closely related to changes in the Na-ion mobility. Analysis of the anomalies in the Na-Na distances, the Debye-Waller factors and the scattering density in the paths connecting neighbouring Na sites strongly suggest that Na-ion diffusion starts at T1, although for T1<T<T2 it occurs preferentially along quasi-1D paths. A fully isotropic diffusion is only observed for T>T2, coinciding with the equalization of all first-neighbor Na-Na distances in the structure [2]. These findings provide new insight on the subtle mechanisms controlling the Na-ion diffusion in the NaxCoO2 family and could be used for the design of related energy materials with improved functional properties. Fig. 1. Fourier difference maps of the z = 0.25 Na planes at T = 50, 320 and 450 K showing the evolution of the residual scattering density in the paths connecting the Na1 and Na2 sites (from ref.[2]).

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Real-time powder diffraction studies of energy materials under non-equilibrium conditions

IUCrJ ◽

10.1107/s2052252517010363 ◽

2017 ◽

Vol 4 (5) ◽

pp. 540-554 ◽

Cited By ~ 15

Author(s):

Vanessa K. Peterson ◽

Josie E. Auckett ◽

Wei-Kong Pang

Keyword(s):

Real Time ◽

Powder Diffraction ◽

Chemical Engineering ◽

Atomic Scale ◽

Energy Materials ◽

Equilibrium Conditions ◽

Energy Devices ◽

Real Time Analysis ◽

Sorbent Materials ◽

Non Equilibrium

Energy materials form the central part of energy devices. An essential part of their function is the ability to reversibly host charge or energy carriers, and analysis of their phase composition and structure in real time under non-equilibrium conditions is mandatory for a full understanding of their atomic-scale functional mechanism. Real-time powder diffraction is increasingly being applied for this purpose, forming a critical step in the strategic chemical engineering of materials with improved behaviour. This topical review gives examples of real-time analysis using powder diffraction of rechargeable battery electrodes and porous sorbent materials used for the separation and storage of energy-relevant gases to demonstrate advances in the insights which can be gained into their atomic-scale function.

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A Heavily Substituted Manganite in an Ordered Nanocomposite for Long-Term Energy Applications

10.26434/chemrxiv.13603268.v1 ◽

2021 ◽

Author(s):

Federico Baiutti ◽

Francesco Maria Chiabrera ◽

Matias Acosta ◽

David R. Diercks ◽

David Parfitt ◽

...

Keyword(s):

Atom Probe ◽

Lanthanum Strontium Manganite ◽

Energy Materials ◽

Local Effects ◽

Energy Devices ◽

Energy Applications ◽

Composite Oxides ◽

Term Energy ◽

Oxygen Isotopic

<div>The implementation of nano-engineered composite oxides opens up the way towards the development of</div><div>a novel class of superior energy materials. Vertically aligned nanocomposites are characterized by a</div><div>coherent, dense array of vertical interfaces, which allows for the extension of local effects to the whole</div><div>volume of the material. Here, we use such a unique architecture to fabricate highly electrochemically</div><div>active nanocomposites of lanthanum strontium manganite and doped ceria with unprecedented stability</div><div>and straight applicability as functional layers in solid state energy devices. Direct evidence of synergistic</div><div>local effects for enhancing the electrochemical performance, stemming from the highly ordered phase</div><div>alternation, is given here for the first time using atom-probe tomography combined with oxygen isotopic</div><div>exchange. Interface-induced cationic substitution, enabling lattice stabilization, is presented as the origin</div><div>of the observed long-term stability. These findings reveal a novel route for materials nano-engineering</div><div>based on the coexistence between local disorder and long-range arrangement.</div>

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A Heavily Substituted Manganite in an Ordered Nanocomposite for Long-Term Energy Applications

10.26434/chemrxiv.13603268 ◽

2021 ◽

Author(s):

Federico Baiutti ◽

Francesco Maria Chiabrera ◽

Matias Acosta ◽

David R. Diercks ◽

David Parfitt ◽

...

Keyword(s):

Atom Probe ◽

Lanthanum Strontium Manganite ◽

Energy Materials ◽

Local Effects ◽

Energy Devices ◽

Energy Applications ◽

Composite Oxides ◽

Term Energy ◽

Oxygen Isotopic

<div>The implementation of nano-engineered composite oxides opens up the way towards the development of</div><div>a novel class of superior energy materials. Vertically aligned nanocomposites are characterized by a</div><div>coherent, dense array of vertical interfaces, which allows for the extension of local effects to the whole</div><div>volume of the material. Here, we use such a unique architecture to fabricate highly electrochemically</div><div>active nanocomposites of lanthanum strontium manganite and doped ceria with unprecedented stability</div><div>and straight applicability as functional layers in solid state energy devices. Direct evidence of synergistic</div><div>local effects for enhancing the electrochemical performance, stemming from the highly ordered phase</div><div>alternation, is given here for the first time using atom-probe tomography combined with oxygen isotopic</div><div>exchange. Interface-induced cationic substitution, enabling lattice stabilization, is presented as the origin</div><div>of the observed long-term stability. These findings reveal a novel route for materials nano-engineering</div><div>based on the coexistence between local disorder and long-range arrangement.</div>

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A heavily subtituted manganite in an ordered nanocomposite for long-term energy applications

10.21203/rs.3.rs-134793/v1 ◽

2021 ◽

Author(s):

Federico Baiutti ◽

Francesco Chiabrera ◽

Matias Acosta ◽

David Diercks ◽

David Parfitt ◽

...

Keyword(s):

Atom Probe ◽

Lanthanum Strontium Manganite ◽

Energy Materials ◽

Local Effects ◽

Energy Devices ◽

Energy Applications ◽

Composite Oxides ◽

Term Energy ◽

Oxygen Isotopic

Abstract The implementation of nano-engineered composite oxides opens up the way towards the development of a novel class of superior energy materials. Vertically aligned nanocomposites are characterized by a coherent, dense array of vertical interfaces, which allows for the extension of local effects to the whole volume of the material. Here, we use such a unique architecture to fabricate highly electrochemically active nanocomposites of lanthanum strontium manganite and doped ceria with unprecedented stability and straight applicability as functional layers in solid state energy devices. Direct evidence of synergistic local effects for enhancing the electrochemical performance, stemming from the highly ordered phase alternation, is given here for the first time using atom-probe tomography combined with oxygen isotopic exchange. Interface-induced cationic substitution, enabling lattice stabilization, is presented as the origin of the observed long-term stability. These findings reveal a novel route for materials nano-engineering based on the coexistence between local disorder and long-range arrangement.

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New Nanocompoite Thermal Interface Materials Based on Graphene Flakes, Mesoscopic Microspheres and Polymers

MATEC Web of Conferences ◽

10.1051/matecconf/201820704002 ◽

2018 ◽

Vol 207 ◽

pp. 04002

Author(s):

Alex A Dmitriev ◽

Alex S Dmitriev ◽

Inna Mikhailova

Keyword(s):

Functional Materials ◽

Thermal Interface Materials ◽

Energy Materials ◽

Volumetric Concentration ◽

Thermal Interface ◽

Energy Devices ◽

Epoxy Polymers ◽

Graphene Flakes ◽

Cooling Devices ◽

Interface Materials

In recent years, there has been a great interest in the development and creation of new functional energy materials, including for improving the energy efficiency of power equipment and for effectively removing heat from energy devices, microelectronics and optoelectronics (power micro electronics, supercapacitors, cooling of processors, servers and data centers). In this paper, the technology of obtaining new nanocomposites based on mesoscopic microspheres, polymers and graphene flakes is considered. The methods of sequential production of functional materials from graphene flakes of different volumetric concentration using epoxy polymers, as well as the addition of monodisperse microspheres are described. Data are given on the measurement of the contact angle and thermal conductivity of these nanocomposites with respect to the creation of thermal interface materials for cooling devices of electronics, optoelectronics and power engineering.

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