Sodium superionic conductors are keys to develop high safety and low cost all-solid-state sodium batteries. Among developed sodium ionic conductors, antiperovskite-type ionic conductors have attracted vast interest due to their high structural tolerance and good formability. Herein, we successfully synthesize Na3OBH4 with cubic antiperovskite structure by solid-state reaction from Na2O and NaBH4. Na3OBH4 exhibits ionic conductivity of 4.4 × 10–3 S cm–1 at room temperature (1.1 × 10–2 S cm–1 at 328 K) and activation energy of 0.25 eV. The ionic conductivity is 4 orders of magnitude higher than the existing antiperovskite Na3OX (X = Cl, Br, I). It is shown that such enhancement is not only due to the specific cubic antiperovskite structure of Na3OBH4 but also because of the rotation of BH4 cluster anion. This work deepens the understanding of the antiperovskite structure and the role of cluster anions for superionic conduction.

Although comprehensive progress has been made in the area of coordination polymer (CP)/metal-organic framework (MOF)-based proton-conducting materials over the past decade, searching for a CP/MOF with stable, intrinsic, high anhydrous proton conductivity that can be directly used as a practical electrolyte in an intermediate-temperature proton-exchange membrane fuel cell assembly for durable power generation remains a substantial challenge. Here, we introduce a new proton-conducting CP, (NH)[Zr(HPO)] (ZrP), which consists of one-dimensional zirconium phosphate anionic chains and fully ordered charge-balancing NH cations. X-ray crystallography, neutron powder diffraction, and variable-temperature solid-state NMR spectroscopy suggest that protons are disordered within an inherent hydrogen-bonded infinite chain of acid-base pairs (N-H···O-P), leading to a stable anhydrous proton conductivity of 1.45 × 10 S·cm at 180 °C, one of the highest values among reported intermediate-temperature proton-conducting materials. First-principles and quantum molecular dynamics simulations were used to directly visualize the unique proton transport pathway involving very efficient proton exchange between NH and phosphate pairs, which is distinct from the common guest encapsulation/dehydration/superprotonic transition mechanisms. ZrP as the electrolyte was further assembled into a H/O fuel cell, which showed a record-high electrical power density of 12 mW·cm at 180 °C among reported cells assembled from crystalline solid electrolytes, as well as a direct methanol fuel cell for the first time to demonstrate real applications. These cells were tested for over 15 h without notable power loss.

The introduction of Prussian blue (PB), an inexpensive pigment material, elegantly breaks the solubility limit of the [Fe(CN) 6 ] 4À/3À electrolyte, and substantially boosts the capacity via an off-electrode chemical reaction. In the reversible redoxtargeting reaction cycles, PB acts as the energy reservoir, while [Fe(CN) 6 ] 4À/3À plays a role in mediating the reactions between the electrode and storage tank. The volumetric capacity surpasses other reported [Fe(CN) 6 ] 4À/3À -based and most other organic aqueous redox flow batteries.

The cation antisite is the most recognizable intrinsic defect type in nickel‐rich layered and olivine‐type cathode materials for lithium‐ion batteries, and important for electrochemical/thermal performance. While how to generate the favorable antisite has not been put forward, herein, by combining first‐principles calculation with neutron powder diffraction (NPD) study, a defect inducing the favorable antisite mechanism is proposed to improve cathode stability, that is, halogen substitution facilitates the neighboring Li and Ni atoms to exchange their sites, forming a more stable local octahedron of halide (LOSH). According to the mechanism, it is demonstrated by NPD that F‐doping not only induces the antisite formation in layered LiNi 0.85 Co 0.075 Mn 0.075 O 2 (LNCM), but also increases the antisite concentration linearly. F substitution (1%) induces 5.7% antisite, and it displays an excellent capacity retention of 94% at 1 C for 200 cycles under 25 °C, outstanding high temperature cyclability (153.4 mAh·g –1 at 1 C for 120 cycles under 55 °C). The onset decomposition temperature increases by 48 °C. The ultrahigh cycling/thermal stability is attributed to the stronger LOSH, and it keeps the structural integrity after long cycling and develops an electrostatic repulsion force between oxygen layers to increase the lattice parameter c , which benefits Li‐ion migration.

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Finding optimal adsorbents to achieve an efficient capture and recovery of sulfur hexafluoride (SF 6 ) from SF 6 /N 2 mixture is of great industrial importance. To address this key challenge, here we present a materials-genomics-accelerated strategy by integrating high-throughput computational screening with subsequent synthesis and adsorption/separation testing of the identified promising material. From over 10140 metal−organic frameworks (MOFs), those with calixarene-analogous pore feature were computationally identified as optimal adsorbents with exceptional SF 6 /N 2 selectivity and SF 6 uptake. The separation mechanism was revealed to be thermodynamically driven owing to the synergistic contribution of multiple hydrogen-bond and van der Waals-type SF 6 /MOF pore wall interactions. As a proof-ofconcept, one of the discovered MOFs was further synthesized, and equilibrium adsorption measurements demonstrated both record SF 6 adsorption capacity as a single component at 0.1 bar (3.39 mmol g −1 ) and SF 6 /N 2 IAST-predicted selectivity (∼266) under ambient conditions. Besides its excellent regeneration and cycling performance, dynamic breakthrough experiments further confirmed the attractiveness of this MOF for SF 6 capture under working conditions.

Pressure-induced switching of magnetism from FM to AFM phase has been observed in layered CrCl3. Concurrently, pressure-induced isostructural transition accompanied with an unusual semiconductor-to-semiconductor transition has been reported.

Solid electrolytes are highly important materials for improving safety, energy density, and reversibility of electrochemical energy storage batteries. However, it is a challenge to modulate the coordination structure of conducting ions, which limits the improvement of ionic conductivity and hampers further development of practical solid electrolytes. Here, we present a skeleton-retained cationic exchange approach to produce a high-performance solid electrolyte of Li 3 Zr 2 Si 2 PO 12 stemming from the NASICON-type superionic conductor of Na 3 Zr 2 Si 2 PO 12 . The introduced lithium ions stabilized in under-coordination structures are facilitated to pass through relatively large conduction bottlenecks inherited from the Na 3 Zr 2 Si 2 PO 12 precursor. The synthesized Li 3 Zr 2 Si 2 PO 12 achieves a low activation energy of 0.21 eV and a high ionic conductivity of 3.59 mS cm −1 at room temperature. Li 3 Zr 2 Si 2 PO 12 not only inherits the satisfactory air survivability from Na 3 Zr 2 Si 2 PO 12 but also exhibits excellent cyclic stability and rate capability when applied to solid-state batteries. The present study opens an innovative avenue to regulate cationic occupancy and make new materials.