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Structure-property relations are central to understanding functional materials, and for battery research the use of neutron powder diffraction to reveal the atomistic and molecular-scale origin of battery performance characteristics is often essential. Although operando experiments of this kind are increasingly common as neutron sources and instrumentation advance, these experiments are hindered by the often large barrier presented by the preparation of whole batteries that yield a neutron diffraction signal from the electrode of interest that is sufficient to extract detailed structural information. This article presents a custom battery that is specifically designed for operando neutron powder diffraction. The battery is a pouch type and contains layers of positive and negative electrodes in a parallel-connecting stack. Importantly, the battery can be easily prepared in most laboratories, is configurable, and can be used with both lithium and sodium charge carriers. This paper provides some example operando neutron powder diffraction studies using this battery. [ABSTRACT FROM AUTHOR]

Metal-organic framework materials (MOFs) have recently been shown in some cases to exhibit strong negative thermal expansion (NTE) behavior, while framework interpenetration has been found to reduce NTE in many materials. Using powder and single-crystal diffraction methods we investigate the thermal expansion behavior of interpenetrated Cu3(btb)2 (MOF-14) and find that it exhibits an anomalously large NTE effect. Temperature-dependent structural analysis shows that, contrary to other interpenetrated materials, in MOF-14 the large positive thermal expansion of weak interactions that hold the interpenetrating networks together results in a low-energy contractive distortion of the overall framework structure, demonstrating a new mechanism for NTE. [ABSTRACT FROM AUTHOR]

Metal-organic framework materials (MOFs) have recently been shown in some cases to exhibit strong negative thermal expansion (NTE) behavior, while framework interpenetration has been found to reduce NTE in many materials. Using powder and single-crystal diffraction methods we investigate the thermal expansion behavior of interpenetrated Cu3(btb)2 (MOF-14) and find that it exhibits an anomalously large NTE effect. Temperature-dependent structural analysis shows that, contrary to other interpenetrated materials, in MOF-14 the large positive thermal expansion of weak interactions that hold the interpenetrating networks together results in a low-energy contractive distortion of the overall framework structure, demonstrating a new mechanism for NTE. [ABSTRACT FROM AUTHOR]

The lattice parameters, cell volume, and structure of a sample of phase pure triclinic tricalcium silicate were determined using in situ, high-temperature synchrotron powder diffraction and full-profile Rietveld refinement. The temperature range covered was from ambient to 740 &degC. Evidence of superstructure was found. The T2 type structure with disordered SiO4 tetrahedra was observed, and an average structure for the subcell (P&1macr;, a = 11.7416(2) &Aring, b = 14.2785(2) Å, c = 13.7732(2) Å, α = 105.129(1)°, β = 94.415(1)°, and γ = 89.889(1)°) is presented. Differential thermal analysis and X-ray fluorescence was also performed. [ABSTRACT FROM AUTHOR]

Ion‐exchange materials are commonly composed of polyelectrolyte networks in which crosslinking preserves macroscopic geometry and prevents dissolution in aqueous conditions. However, crosslinking inherently inhibits efficient swelling and mass transfer during ion‐exchange processes. Herein, a one‐step polymerization‐induced microphase separation (PIMS) approach directly using water and linear polystyrene sulfonate macromolecular chain transfer agents (macroCTAs) is developed to engineer bicontinuous nanostructured materials with rapid ion‐exchange capabilities. These materials feature water‐swollen liquid‐like polyelectrolyte domain embedded in a rigid polymer network, where the domain spacing, as determined by small angle X‐ray scattering experiments, is precisely modulated between 15 and 89 nm based on the molecular weight of the macroCTA used. As the bicontinuous nanostructure enables rapid mass transfer throughout the material bulk, the 3D printed PIMS materials are able to rapidly remove model charged dyes from solution, exhibiting a mass transfer coefficient ≈35 times higher than commercially available counterparts. This work is the first example demonstrating direct self‐assembly of water into continuous nanochannels in a well‐controlled manner as supported by time‐resolved small‐angle neutron scattering experiments during polymerization. Moreover, these nanostructured materials are readily produced using commercially available 3D printers, enabling unparalleled high‐resolution fabrication of targeted complex structures, including accurately controllable macroporous geometries and surface areas. [ABSTRACT FROM AUTHOR]

Wadsley‐Roth niobium oxide phases have attracted extensive research interest recently as promising battery anodes. We have synthesized the niobium‐molybdenum oxide shear phase (Nb, Mo)13O33 with superior electrochemical Li‐ion storage performance, including an ultralong cycling lifespan of at least 15000 cycles. During electrochemical cycling, a reversible single‐phase solid‐solution reaction with lithiated intermediate solid solutions is demonstrated using in situ X‐ray diffraction, with the valence and short‐range structural changes of the electrode probed by in situ Nb and Mo K‐edge X‐ray absorption spectroscopy. This work reveals that the superior stability of niobium molybdenum oxides is underpinned by changes in octahedral distortion during electrochemical reactions, and we report an in‐depth understanding of how this stabilizes the oxide structure during cycling with implications for future long‐life battery material design. [ABSTRACT FROM AUTHOR]

Wadsley‐Roth niobium oxide phases have attracted extensive research interest recently as promising battery anodes. We have synthesized the niobium‐molybdenum oxide shear phase (Nb, Mo)13O33 with superior electrochemical Li‐ion storage performance, including an ultralong cycling lifespan of at least 15000 cycles. During electrochemical cycling, a reversible single‐phase solid‐solution reaction with lithiated intermediate solid solutions is demonstrated using in situ X‐ray diffraction, with the valence and short‐range structural changes of the electrode probed by in situ Nb and Mo K‐edge X‐ray absorption spectroscopy. This work reveals that the superior stability of niobium molybdenum oxides is underpinned by changes in octahedral distortion during electrochemical reactions, and we report an in‐depth understanding of how this stabilizes the oxide structure during cycling with implications for future long‐life battery material design. [ABSTRACT FROM AUTHOR]

Despite being the major cause of safety and performance issues in lithium metal batteries, experimental difficulties in quantifying directly the morphology of lithium deposited at electrode surfaces have meant that the mechanism of metallic lithium growth within batteries remains elusive. This study demonstrates that quantitative detail about the morphology of metallic lithium within batteries can be derived non‐destructively and directly using in situ ultra‐small and small‐angle neutron scattering. This information is obtained over a large electrode area in cells where lithium deposition processes are typical of real‐world applications. Complex variations of surface area and interfacial distances 1–10 µm and 100–300 nm are revealed in size that are influenced by current density and cell cycling history, providing valuable insight into the growth of metallic lithium features detrimental to battery performance. Such quantitative insight into the process of lithium growth is required for the development of safer high‐performance lithium metal batteries. [ABSTRACT FROM AUTHOR]

Oxygen‐ion conducting perovskite oxides are important functional materials for solid oxide fuel cells and oxygen‐permeable membranes operating at high temperatures (>500 °C). Co‐doped perovskites have recently shown their potential to boost oxygen‐related kinetics, but challenges remain in understanding the underlying mechanisms. This study unveils the local cation arrangement as a new key factor controlling oxygen kinetics in perovskite oxides. By single‐ and co‐doping Nb5+ and Ta5+ into SrCoO3‐δ, dominant factors affecting oxygen kinetics, such as lattice geometry, cobalt states, and oxygen vacancies, which are confirmed by neutron and synchrotron X‐ray diffraction as well as high‐temperature X‐ray absorption spectroscopy, are controlled. The combined experimental and theoretical study unveils that co‐doping likely leads to higher cation dispersion at the B‐site compared to single‐doping. Consequently, a high‐entropy configuration enhances oxygen ion migration in the lattice, translating to improved oxygen reduction activity. [ABSTRACT FROM AUTHOR]

In operando powder diffraction remains one of the most powerful tools for non‐destructive investigation of battery electrode materials. While in operando X‐ray, especially synchrotron radiation, powder diffraction is by now a routine experimental technique, in operando neutron powder diffraction is still less established. We present a new electrochemical cell for in operando neutron powder diffraction, which is, first and foremost, easy to use, but can also cycle electrode materials under electrochemical conditions close to those achieved using standard laboratory cells. The cell has been designed in multiple sizes, and high‐quality electrochemical and neutron powder diffraction data is presented for sample sizes as low as 48 mg total active material. The cell handles lithium‐ion and sodium‐ion materials equally well, with no difference in how the cell is prepared and assembled. The cell is intended to be used as sample environment at powder diffractometers at the neutron facilities MLZ, ORNL and ACNS. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are promising solid sorbents, showing gas selectivity and uptake capacities relevant to many important applications, notably in the energy sector. To improve and tailor the sorption properties of these materials for such applications, it is necessary to gain an understanding of their working mechanisms at the atomic and molecular scale. Specifically, it is important to understand how features such as framework porosity, topology, chemical functionality and flexibility underpin sorbent behaviour and performance. Such information is obtained through interrogation of structure-function relationships, with neutron powder diffraction (NPD) being a particularly powerful characterization tool. The combination of NPD with first-principles density functional theory (DFT) calculations enables a deep understanding of the sorption mechanisms, and the resulting insights can direct the future development of MOF sorbents. In this paper, experimental approaches and investigations of two example MOFs are summarized, which demonstrate the type of information and the understanding into their functional mechanisms that can be gained. Such information is critical to the strategic design of new materials with targeted gas-sorption properties. [ABSTRACT FROM AUTHOR]

Oxides composed of an oxygen framework and interstitial cations are promising cathode materials for lithium‐ion batteries. However, the instability of the oxygen framework under harsh operating conditions results in fast battery capacity decay, due to the weak orbital interactions between cations and oxygen (mainly 3d–2p interaction). Here, a robust and endurable oxygen framework is created by introducing strong 4s–2p orbital hybridization into the structure using LiNi0.5Mn1.5O4 oxide as an example. The modified oxide delivers extraordinarily stable battery performance, achieving 71.4 % capacity retention after 2000 cycles at 1 C. This work shows that an orbital‐level understanding can be leveraged to engineer high structural stability of the anion oxygen framework of oxides. Moreover, the similarity of the oxygen lattice between oxide electrodes makes this approach extendable to other electrodes, with orbital‐focused engineering a new avenue for the fundamental modification of battery materials. [ABSTRACT FROM AUTHOR]

Oxides composed of an oxygen framework and interstitial cations are promising cathode materials for lithium‐ion batteries. However, the instability of the oxygen framework under harsh operating conditions results in fast battery capacity decay, due to the weak orbital interactions between cations and oxygen (mainly 3d–2p interaction). Here, a robust and endurable oxygen framework is created by introducing strong 4s–2p orbital hybridization into the structure using LiNi0.5Mn1.5O4 oxide as an example. The modified oxide delivers extraordinarily stable battery performance, achieving 71.4 % capacity retention after 2000 cycles at 1 C. This work shows that an orbital‐level understanding can be leveraged to engineer high structural stability of the anion oxygen framework of oxides. Moreover, the similarity of the oxygen lattice between oxide electrodes makes this approach extendable to other electrodes, with orbital‐focused engineering a new avenue for the fundamental modification of battery materials. [ABSTRACT FROM AUTHOR]

Spinel LiNi0.5Mn1.5O4 (LNMO) is a promising cathode candidate for the next‐generation high energy‐density lithium‐ion batteries (LIBs). Unfortunately, the application of LNMO is hindered by its poor cycle stability. Now, site‐selectively doped LNMO electrode is prepared with exceptional durability. In this work, Mg is selectively doped onto both tetrahedral (8a) and octahedral (16c) sites in the Fd3‾ m structure. This site‐selective doping not only suppresses unfavorable two‐phase reactions and stabilizes the LNMO structure against structural deformation, but also mitigates the dissolution of Mn during cycling. Mg‐doped LNMOs exhibit extraordinarily stable electrochemical performance in both half‐cells and prototype full‐batteries with novel TiNb2O7 counter‐electrodes. This work pioneers an atomic‐doping engineering strategy for electrode materials that could be extended to other energy materials to create high‐performance devices. [ABSTRACT FROM AUTHOR]

Spinel LiNi0.5Mn1.5O4 (LNMO) is a promising cathode candidate for the next‐generation high energy‐density lithium‐ion batteries (LIBs). Unfortunately, the application of LNMO is hindered by its poor cycle stability. Now, site‐selectively doped LNMO electrode is prepared with exceptional durability. In this work, Mg is selectively doped onto both tetrahedral (8a) and octahedral (16c) sites in the Fd3‾ m structure. This site‐selective doping not only suppresses unfavorable two‐phase reactions and stabilizes the LNMO structure against structural deformation, but also mitigates the dissolution of Mn during cycling. Mg‐doped LNMOs exhibit extraordinarily stable electrochemical performance in both half‐cells and prototype full‐batteries with novel TiNb2O7 counter‐electrodes. This work pioneers an atomic‐doping engineering strategy for electrode materials that could be extended to other energy materials to create high‐performance devices. [ABSTRACT FROM AUTHOR]

LiCoO2 (LCO) with average particle distribution of 8 μm (LCO‐A) and 11 μm (LCO‐B) exhibit substantial differences in cycle performance. The half‐cells have similar first‐cycle discharge capacities of 173 and 175 mAh/g at 0.25 C, but after 100 cycles, the discharge capacities are substantially different, that is, 114 and 141 mAh/g for LCO‐A and LCO‐B, respectively. Operando neutron powder diffraction of full LCO||Li4Ti5O12 batteries show differences in the LCO reaction mechanism underpinning the electrochemical behavior. LCO‐A follows a purely solid solution reaction during cycling compared to the solid solution and two‐phase reaction mechanism in LCO‐B. The absence of the two‐phase reaction in LCO‐A is consistent with a homogeneous distribution of Li throughout the particle. The two‐phase reaction in LCO‐B reflects two distinguishable distributions of Li within the particles. The faster capacity decay in LCO‐A is correlated to an increase in electrode cracking during battery cycles. [ABSTRACT FROM AUTHOR]

Reaction of the chloranilate dianion with Y(NO3)3 in the presence of Et4N+ in the appropriate proportions results in the formation of (Et4N)[Y(can)2], which consists of anionic square‐grid coordination polymer sheets with interleaved layers of counter‐cations. These counter‐cations, which serve as squat pillars between [Y(can)2] sheets, lead to alignment of the square grid sheets and the subsequent generation of square channels running perpendicular to the sheets. The crystals are found to be porous and retain crystallinity following cycles of adsorption and desorption. This compound exhibits a high affinity for volatile guest molecules, which could be identified within the framework by crystallographic methods. In situ neutron powder diffraction indicates a size‐shape complementarity leading to a strong interaction between host and guest for CO2 and CH4. Single‐crystal X‐ray diffraction experiments indicate significant interactions between the host framework and discrete I2 or Br2 molecules. A series of isostructural compounds (cat)[MIII(X‐an)2] with M=Sc, Gd, Tb, Dy, Ho, Er, Yb, Lu, Bi or In, cat=Et4N, Me4N and X‐an=chloranilate, bromanilate or cyanochloranilate bridging ligands have been generated. The magnetic properties of representative examples (Et4N)[Gd(can)2] and (Et4N)[Dy(can)2] are reported with normal DC susceptibility but unusual AC susceptibility data noted for (Et4N)[Gd(can)2]. An extensive family of square grid anionic coordination polymers is formed by the combination of 8‐coordinate trivalent metal ions with bridging chloranilate ligands. Alignment of the square grid networks produces channels that are able to accommodate a variety species. The location of guest molecules within the channels has been determined using both X‐ray and neutron diffraction. [ABSTRACT FROM AUTHOR]

Invited for this month's cover is the group of Daniel R. Sørensen at the University of Aarhus (Denmark) and at the University of Lund (Sweden). The cover picture shows a battery cell designed for in operando neutron powder diffraction. The picture seeks to illustrate the experiment process where lithium ions are moving into the crystal structure of the battery cathode during discharge. This leads to changes in the crystal structure that are very important to understand for optimizing the battery materials. These structural changes are probed in operando by neutron powder diffraction, and neutrons are especially suited for probing the location of Li‐ion compared with similar techniques such as X‐ray diffraction. The beauty of using neutrons is also that their penetrating power allows for investigating the battery without the need for windows of any kind. Read the full text of their Research Article at 10.1002/cmtd.202200046. [ABSTRACT FROM AUTHOR]

Abstract: The interdependent effects of temperature and guest uptake on the structure of the ultramicroporous metal–organic framework [Cu3(cdm)4] (cdm=C(CN)2(CONH2)−) were explored in detail by using in situ neutron scattering and density functional theory calculations. The tetragonal lattice displays an anisotropic thermal response related to a hinged “lattice‐fence” mechanism, unusual for this topology, which is facilitated by pivoting of the rigid cdm anion about the Cu nodes. Calculated pore‐size metrics clearly illustrate the potential for temperature‐mediated adsorption in ultramicroporous frameworks due to thermal fluctuations of the pore diameter near the value of the target guest kinetic diameter, though in [Cu3(cdm)4] this is counteracted by a competing contraction of the pore with increasing temperature as a result of the anisotropic lattice response. [ABSTRACT FROM AUTHOR]

A system for positioning powder samples in top-loading cryofurnaces during neutron scattering experiments, while facilitating the successive delivery of gas doses at set temperatures to the sample, has been designed and tested. The positioning system is compatible with a Hiden Isochema IMI instrument as a gas-dosing platform, enabling gases to be delivered to the sample through a centrally located and thermally stabilized capillary line and valve. The positioning system separates into an upper and a lower section, with the lower section enabling the sample to be isolated and inserted into a glove box. This work describes the system using example neutron powder diffraction results obtained with this system in closed-cycle cryofurnaces. [ABSTRACT FROM AUTHOR]

Oxides composed of an oxygen framework and interstitial cations are promising cathode materials for lithium‐ion batteries. However, the instability of the oxygen framework under harsh operating conditions results in fast battery capacity decay, due to the weak orbital interactions between cations and oxygen (mainly 3d–2p interaction). Here, a robust and endurable oxygen framework is created by introducing strong 4s–2p orbital hybridization into the structure using LiNi0.5Mn1.5O4 oxide as an example. The modified oxide delivers extraordinarily stable battery performance, achieving 71.4 % capacity retention after 2000 cycles at 1 C. This work shows that an orbital‐level understanding can be leveraged to engineer high structural stability of the anion oxygen framework of oxides. Moreover, the similarity of the oxygen lattice between oxide electrodes makes this approach extendable to other electrodes, with orbital‐focused engineering a new avenue for the fundamental modification of battery materials. [ABSTRACT FROM AUTHOR]

Li‐rich layered oxides (LLOs) can deliver almost double the capacity of conventional electrode materials such as LiCoO2 and LiMn2O4; however, voltage fade and capacity degradation are major obstacles to the practical implementation of LLOs in high‐energy lithium‐ion batteries. Herein, hexagonal La0.8Sr0.2MnO3−y (LSM) is used as a protective and phase‐compatible surface layer to stabilize the Li‐rich layered Li1.2Ni0.13Co0.13Mn0.54O2 (LM) cathode material. The LSM is MnOM bonded at the LSM/LM interface and functions by preventing the migration of metal ions in the LM associated with capacity degradation as well as enhancing the electrical transfer and ionic conductivity at the interface. The LSM‐coated LM delivers an enhanced reversible capacity of 202 mAh g−1 at 1 C (260 mA g−1) with excellent cycling stability and rate capability (94% capacity retention after 200 cycles and 144 mAh g−1 at 5 C). This work demonstrates that interfacial bonding between coating and bulk material is a successful strategy for the modification of LLO electrodes for the next‐generation of high‐energy Li‐ion batteries. [ABSTRACT FROM AUTHOR]

Potassium‐ion batteries (PIBs) are an emerging, affordable, and environmentally friendly alternative to lithium‐ion batteries, with their further development driven by the need for suitably performing electrode materials capable of reversibly accommodating the relatively large K+. Layer‐structured manganese oxides are attractive as electrodes for PIBs, but suffer from structural instability and sluggish kinetics of K+ insertion/extraction, leading to poor rate capability. Herein, cobalt is successfully introduced at the manganese site in the KxMnO2 layered oxide electrode material and it is shown that with only 5% Co, the reversible capacity increases by 30% at 22 mA g‐1 and by 92% at 440 mA g‐1. In operando synchrotron X‐ray diffraction reveals that Co suppresses Jahn–Teller distortion, leading to more isotropic migration pathways for K+ in the interlayer, thus enhancing the ionic diffusion and consequently, rate capability. The detailed analysis reveals that additional phase transitions and larger volume change occur in the Co‐doped material as a result of layer gliding, with these associated with faster capacity decay, despite the overall capacity remaining higher than the pristine material, even after 500 cycles. These results assert the importance of understanding the detailed structural evolution that underpins performance that will inform the strategic design of electrode materials for high‐performance PIBs. [ABSTRACT FROM AUTHOR]

Review: [100 refs. [ABSTRACT FROM AUTHOR]

Ca4[Al6O12]SO4 (yeelimite) is prepared by solid state reaction of CaCO3, Al2O3, and CaSO4 (1300 °C, 4 h, slow cooling). [ABSTRACT FROM AUTHOR]