Overcoming the probing-depth dilemma in spectroscopic analyses of batteries with muon-induced X-ray emission (MIXE).

Battery research often encounters the challenge of determining chemical information, such as composition and elemental oxidation states, of a layer buried within a cell stack in a non-destructive manner. Spectroscopic techniques based on X-ray emission or absorption are well-suited and commonly employed to reveal this information. However, the attenuation of X-rays as they travel through matter creates a challenge when trying to analyze layers buried at depths exceeding hundred micrometers from the sample's surface.

Elucidating the pressure-induced enhancement of ionic conductivity in sodium -hydroborate electrolytes for all-solid-state batteries.

Unlabelled: Hydroborates are an emerging class of solid electrolytes for all-solid-state batteries. Here, we investigate the impact of pressure on the crystal structure and ionic conductivity of a close-hydroborate salt consisting of NaBH and NaBH. Two NaBH:NaBH ratios were studied, 1:1 and 1:3.

Transient Elastomers with High Dielectric Permittivity for Actuators, Sensors, and Beyond.

Dielectric elastomers (DEs) are key materials in actuators, sensors, energy harvesters, and stretchable electronics. These devices find applications in important emerging fields such as personalized medicine, renewable energy, and soft robotics. However, even after years of research, it is still a great challenge to achieve DEs with increased dielectric permittivity and fast recovery of initial shape when subjected to mechanical and electrical stress.

Correction: Experimental investigation of Mg(BH) dimensionality, materials for energy storage applications.

Correction for 'Experimental investigation of Mg(BH) dimensionality, materials for energy storage applications' by Romain Moury , , 2020, , 12168-12173, https://doi.org/10.1039/D0DT02170A.

Study of the Temperature- and Pressure-Dependent Structural Properties of Alkali Hydrido--borate Compounds.

In this work, we report on the structural properties of alkali hydrido--(car)borates, a promising class of solid-state electrolyte materials, using high-pressure and temperature-dependent X-ray diffraction experiments combined with density functional theory (DFT) calculations. The mechanical properties are determined via pressure-dependent diffraction studies and DFT calculations; the shear moduli appear to be very low for all studied compounds, revealing their high malleability (that can be beneficial for the manufacturing and stable cycling of all-solid-state batteries). The thermodiffraction experiments also reveal a high coefficient of thermal expansion for these materials.

Thermal and Electrochemical Interface Compatibility of a Hydroborate Solid Electrolyte with 3 V-Class Cathodes for All-Solid-State Sodium Batteries.

Thermal stability of solid electrolytes and their compatibility with battery electrodes are key factors to ensure stable cycling and high operational safety of all-solid-state batteries. Here, we study the compatibility of a hydroborate solid electrolyte Na(BH)(BH) with 3 V-class cathode active materials: NaCrO, NaMnO, and NaFeO. Among these layered sodium transition metal oxide cathodes, NaCrO shows the highest thermal compatibility in contact with the hydroborate solid electrolyte up to 525 °C in the discharged state.

Experimental investigation of Mg(BH) dimensionality, materials for energy storage applications.

Mg(B3H8)2 is a crucial reaction intermediate in the thermal decomposition of the hydrogen storage material Mg(BH4)2 and is discussed as a potential solid-state Mg-ion conductor. We successfully synthesized unsolvated Mg(B3H8)2 and highlight that Mg(B3H8)2 exists mainly as a low-dimensional solid. In addition, the Mg2+ conductivity was evaluated to be 1.

Direct Solution-Based Synthesis of Na (B H )(B H ) Solid Electrolyte.

All-solid-state batteries (ASSBs) promise higher power and energy density than batteries based on liquid electrolytes. Recently, a stable 3 V ASSB based on the super ionic conductor (1 mS cm near room temperature) Na (B H )(B H ) has demonstrated excellent cycling stability. This study concerns the development of a five-step, scalable, and solution-based synthesis of Na (B H )(B H ).

Pressure-induced phase transitions in NaBH, structural investigation on a candidate for solid-state electrolyte.

closo-Borates, such as NaBH, are an emerging class of ionic conductors that show promising chemical, electrochemical and mechanical properties as electrolytes in all-solid-state batteries. Motivated by theoretical predictions, high-pressure in situ powder X-ray diffraction on NaBH was performed and two high-pressure phases are discovered. The first phase transition occurs at 0.

Epitaxial Thin Films as a Model System for Li-Ion Conductivity in LiTiO.

Using an epitaxial thin-film model system deposited by pulsed laser deposition (PLD), we study the Li-ion conductivity in LiTiO, a common anode material for Li-ion batteries. Epitaxy, phase purity, and film composition across the film thickness are verified employing out-of-plane and in-plane X-ray diffraction, transmission electron microscopy, time-of-flight mass spectrometry, and elastic recoil detection analysis. We find that epitaxial LiTiO behaves like an ideal ionic conductor that is well described by a parallel RC equivalent circuit, with an ionic conductivity of 2.

Dynamics of the Coordination Complexes in a Solid-State Mg Electrolyte.

Coordination complexes of magnesium borohydride show promising properties as solid electrolytes for magnesium ion batteries and warrant a thorough microscopic description of factors governing their mobility properties. Here, the dynamics of Mg(BH)-diglyme on the atomic level are investigated by means of quasielastic neutron scattering supported by density functional theory calculations and IR and NMR spectroscopy. Employing deuterium labeling, we can unambiguously separate all the hydrogen-containing electrolyte components, which facilitate Mg transport, and provide a detailed analytical description of their motions on the picosecond time scale.

Effect of Gallium Substitution on Lithium-Ion Conductivity and Phase Evolution in Sputtered LiGa LaZrO Thin Films.

Replacing the liquid electrolyte in conventional lithium-ion batteries with thin-film solid-state lithium-ion conductors is a promising approach for increasing energy density, lifetime, and safety. In particular, LiLaZrO is appealing due to its high lithium-ion conductivity and wide electrochemical stability window. Further insights into thin-film processing of this material are required for its successful integration into solid-state batteries.

Synthesis, stability and Li-ion mobility of nanoconfined LiBH.

This communication presents the first synthesis of nanoconfined Lithium closo-borate, LiBH, using nanoporous SiO as scaffold. The yield of LiBH is up to 94 mol%. The as-synthesized nanoconfined LiBH exhibits a structural transition around 380 °C and conversion to H-deficiency LiBH at 580 °C.

Post-Synthesis Amine Borane Functionalization of a Metal-Organic Framework and Its Unusual Chemical Hydrogen Release Phenomenon.

A novel strategy for post-synthesis amine borane functionalization of MOFs under gas-solid phase transformation, utilizing gaseous diborane, is reported. The covalently confined amine borane derivative decorated on the framework backbone is stable when preserved at low temperature, but spontaneously liberates soft chemical hydrogen at room temperature, leading to the development of an unusual borenium type species (-NH=BH ) ion-paired with a hydroborate anion. Furthermore, the unsaturated amino borane (-NH=BH ) and the μ-iminodiborane (-μ-NHB H ) were detected as final products.

Magnesium Ethylenediamine Borohydride as Solid-State Electrolyte for Magnesium Batteries.

Solid-state magnesium ion conductors with exceptionally high ionic conductivity at low temperatures, 5 × 10 Scm at 30 °C and 6 × 10 Scm at 70 °C, are prepared by mechanochemical reaction of magnesium borohydride and ethylenediamine. The coordination complexes are crystalline, support cycling in a potential window of 1.2 V, and allow magnesium plating/stripping.

A highly stable sodium solid-state electrolyte based on a dodeca/deca-borate equimolar mixture.

Na(BH)(BH), a new solid-state sodium electrolyte is shown to offer high Na conductivity of 0.9 mS cm at 20 °C, excellent thermal stability up to 300 °C, and a large electrochemical stability window of 3 V including stability towards sodium metal anodes, all essential prerequisites for a stable room-temperature 3 V all-solid-state sodium-ion battery.

Confinement Effects for Lithium Borohydride: Comparing Silica and Carbon Scaffolds.

LiBH is a promising material for hydrogen storage and as a solid-state electrolyte for Li ion batteries. Confining LiBH in porous scaffolds improves its hydrogen desorption kinetics, reversibility, and Li conductivity, but little is known about the influence of the chemical nature of the scaffold. Here, quasielastic neutron scattering and calorimetric measurements were used to study support effects for LiBH confined in nanoporous silica and carbon scaffolds.

Controllable decomposition of Ca(BH) for reversible hydrogen storage.

Ca(BH) could reversibly store 9.6 wt% hydrogen based on the overall reaction of Ca(BH) → 1/3CaB + 2/3CaH + 10/3H. Formation of CaB instead of elemental boron and/or high boranes (e.

"Water-in-salt" electrolytes enable the use of cost-effective aluminum current collectors for aqueous high-voltage batteries.

The extended electrochemical stability window offered by highly concentrated electrolytes allows the operation of aqueous batteries at voltages significantly above the thermodynamic stability limit of water, at which the stability of the current collector potentially limits the cell voltage. Here we report the observation of suppressed anodic dissolution of aluminum in "water-in-salt" electrolytes enabling roll-to-roll electrode fabrication for high-voltage aqueous lithium-ion batteries on cost-effective light-weight aluminum current collectors using established lithium-ion battery technology.

Formation of CaB6 in the thermal decomposition of the hydrogen storage material Ca(BH4)2.

Using a combination of high resolution X-ray powder diffraction and X-ray Raman scattering spectroscopy at the B K- and Ca L2,3-edges, we analyzed the reaction products of Ca(BH4)2 after annealing at 350 °C and 400 °C under vacuum conditions. We observed the formation of nanocrystalline/amorphous CaB6 mainly and found only small contributions from amorphous B for annealing times larger than 2 h. For short annealing times of 0.

Complex metal borohydrides: multifunctional materials for energy storage and conversion.

With the limited supply of fossil fuels and their adverse effect on the climate and the environment, it has become a global priority to seek alternate sources of energy that are clean, abundant, and sustainable. While sources such as solar, wind, and hydrogen can meet the world's energy demand, considerable challenges remain to find materials that can store and/or convert energy efficiently. This topical review focuses on one such class of materials, namely, multi-functional complex metal borohydrides that not only have the ability to store sufficient amount of hydrogen to meet the needs of the transportation industry, but also can be used for a new generation of metal ion batteries and solar cells.

In situ characterization of the decomposition behavior of Mg(BH4)2 by X-ray Raman scattering spectroscopy.

We present an in situ study of the thermal decomposition of Mg(BH4)2 in a hydrogen atmosphere of up to 4 bar and up to 500 °C using X-ray Raman scattering spectroscopy at the boron K-edge and the magnesium L2,3-edges. The combination of the fingerprinting analysis of both edges yields detailed quantitative information on the reaction products during decomposition, an issue of crucial importance in determining whether Mg(BH4)2 can be used as a next-generation hydrogen storage material. This work reveals the formation of reaction intermediate(s) at 300 °C, accompanied by a significant hydrogen release without the occurrence of stable boron compounds such as amorphous boron or MgB12H12.

A novel method for the synthesis of solvent-free Mg(B3H8)2.

This communication presents a novel and solvent-free method to synthesise Mg(B3H8)2 via the gas-solid reaction between B2H6 and Mg2NiH4, which overcomes the limitations of wet chemical methods requiring solvent removal.