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Sodium metal batteries have emerged as potential rivals to lithium‐ion batteries. Nevertheless, maintaining a stable sodium metal anode under harsh conditions (current density >10 mA cm−2) is extremely challenging. The primary issue is the highly reactive sodium metal continuously reacts with the electrolyte to form a thick and loose solid electrolyte film. The tip effect causes sodium ions (Na+) accumulated in the bulge resulting in uneven deposition. In this paper, a unique artificial interfacial layer (Ag nanoparticles distributed in NaClO4‐based matrix) is prepared on the surface of a metallic sodium anode using in situ displacement reaction. Ag particles arranged at the bottom of the artificial layer act as effective nucleation sites helping Na+ deposit uniformly, while the built‐in electric field formed between Ag in the middle/top of the artificial layer and the sodium accelerates the migration of Na+ in the interfacial layer during the deposition and reduce the polarization. Such important properties further allow the steady operation of modified sodium metal batteries in very harsh conditions. The symmetric battery achieves reversible stripping/plating for over 1000 h under high current density (10 mA cm−2). Moreover, the full cell coupled with a high‐loading Na3V2(PO4)3 cathode (20 mg cm−2) presents a stable cycle performance. [ABSTRACT FROM AUTHOR]

Following logic in the silicon semiconductor industry, the existence of native oxide and suitable fabrication technology is essential for 2D semiconductors in planar integronics, which are surface‐sensitive to typical coating technologies. To date, very few types of integronics are found to possess this feature. Herein, the 2D Bi2O2Te developed recently is reported to possess large‐area synthesis and controllable thermal oxidation behavior toward single‐crystal native oxides. This shows that surface‐adsorbed oxygen atoms are inclined to penetrate across [Bi2O2]n2n+ layers and bond with the underlying [Te]n2n− at elevated temperatures, transforming directly into [TeO4]n2n− with the basic architecture remaining stable. The oxide can be adjusted to form in an accurate layer‐by‐layer manner with a low‐stress sharp interface. The native oxide Bi2TeO6 layer (bandgap of ≈2.9 eV) exhibits visible‐light transparency and is compatible with wet‐chemical selective etching technology. These advances demonstrate the potential of Bi2O2Te in planar‐integrated functional nanoelectronics such as tunnel junction devices, field‐effect transistors, and memristors. [ABSTRACT FROM AUTHOR]

Electrolyte solvent, salt, and additive directly determine many battery indicators such as voltage limit, safe reliability, and temperature limit. In Ca‐metal batteries, suitable electrolyte and interphase are necessary to achieve reversible calcium plating/stripping, which is challenging for F‐based salts at room temperature. Ion transport and charge transfer in calcium batteries with Ca(BF4)2‐NaPF6 electrolyte are regulated for the first time by altering solvent and salt categories and ratios, achieving adjustable interphase species and microstructure, calcium deposition/dissolution overpotentials, and cycling stability. The optimized electrolyte of 0.1 m Ca(BF4)2‐0.9 m NaPF6 in ethylene carbonate/diethyl carbonate/dimethyl carbonate/ethyl methyl carbonate (7:1:6:6, v/v) contributes to the most stable Ca plating/stripping cycling and the weakest overpotential, as well as Na/Ca‐based hybrid solid electrolyte interphases including proper amount of organic matter. Ca‐metal batteries with the optimized electrolyte achieve an ultrahigh reversible capacity of ≈290 mAh g−1 (at 200 mA g−1 and 1.2–4.5 V), almost four times more than that of counterpart ones (≈65 mAh g−1), equivalent to energy/power performance of ≈616 Wh kg−1 at 429 W kg−1 among the best ones for multivalent ion rechargeable metal batteries. [ABSTRACT FROM AUTHOR]

Reported herein is an active and durable CoN‐containing oxygen evolution reaction (OER) electrocatalyst which efficiently functions in a neutral medium (pH ≈7). The composite material (N, S)‐RGO@CoN is synthesized by delicate atomic layer deposition (ALD) of CoN on a nitrogen and sulfur (N, S) co‐doped reduced graphene oxide (RGO) substrate. Representative results of the comprehensive study are: 1) The flower‐like sphere RGO substrate prepared by spray drying method features rich physical and chemical properties, which are beneficial for rapid mass/charge transfer to improve the intrinsic OER process; 2) the optimal ALD material for OER tests is afforded by tuning spray conditions and ALD parameters. Versatile structural and compositional characterizations confirm uniform growth and strong chemical coupling of nanostructured CoN on (N, S)‐RGO matrix; 3) the material is electrocatalytically active and durable in a neutral electrolyte, recording an OER overpotential of 220 mV at a current density of 10 mA cm−2 and stability of 20 h continuous catalysis at 20 mA cm−2 with nearly 100% Faradic efficiency; 4) Upon the experimental studies and density functional theory calculations, the eventual mechanism of remarkable OER activity conforms to the structural fate of ALD CoN electronic coupling to the carbon substrate. [ABSTRACT FROM AUTHOR]

An efficient and durable oxygen evolution reaction (OER) electrocatalyst consisting of TiN @ Co5.47N is constructed by the integration of plasma nitriding and a delicate atomic layer deposition (ALD) CoxN process. Representative results of comprehensive study are: 1) the material is electrocatalytically active in universal medium. The OER overpotentials are 398, 248, and 411 mV in acidic, basic, and neutral electrolyte, respectively, at a current density of 50 mA cm−2; 2) the material records an impressive long‐term stability of continuous catalysis for 1500 h, during which the overpotential increases by only 1.3%. The synergistically electronic interaction between TiN and ALD Co5.47N, as well as a protective yet active CoTi layered double hydroxides (CoTi LDH) layer formed simultaneously at the interface/surface of TiN @ Co5.47N during the electrocatalytic process, is speculated to be responsible for the superior OER performance; 3) the surface Co atoms other than Ti of CoTi LDH, exhibit electrocatalytic activity with dramatically low overpotential based on density functional theory calculations. [ABSTRACT FROM AUTHOR]

Morphology reshaping or reconfiguration, a concept widely used in plastic surgery, energy harvesting, and reconfigurable robots, is introduced for the first time to construct densified electrodes and realize compact Li‐ion storage desirable for high specific energy storage field. Hausmannite‐based hybrid materials, as a proof‐of‐concept prototype, engineered by 1‐methyl‐2‐pyrrolidinone‐soluble surface/interface organic encapsulation, which is crucial in reshaping, exhibit a remarkable increase in the volumetric capacity of more than five times after this process (≈1889 Ah L−1 vs ≈322 Ah L−1). With the simultaneous maintenance of the intrinsic nature, good contact, and no collapsed/agglomerated unit structures of the materials in electrodes, the design affords a maximal increase in the packing compactness and manifests no sacrifice of the reversible ion storage capability (1150 mAh g−1 at 40 mA g−1), stable cycling (≈100% capacity retention), high rate performance (185 mAh g−1 at 10 A g−1), and long lifespan (1000 cycles with 108% capacity retention, ≈455 mAh g−1 at 3 A g−1) for relatively highly loaded electrodes (active materials: 1.20–5.34 mg cm−2). The concept may not only shed new light on fabricating advanced Si‐based and other high capacity–related densified Li storage electrodes but also inject fresh vitality into the field of high‐density power sources. [ABSTRACT FROM AUTHOR]