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Hybrid capacitors exhibit promise to bridge the gap between rechargeable high‐energy density batteries and high‐power density supercapacitors. This separation is due to sluggish ion/electron diffusion and inferior structural stability of battery‐type materials. Here, a topochemistry‐driven method for constructing expanded 2D rhenium selenide intercalated by nitrogen‐doped carbon hybrid (E‐ReSe2@INC) with a strong‐coupled interface and weak van der Waals forces, is proposed. X‐ray absorption spectroscopy analysis dynamically tracks the transformation from ReO into ReC bonds. The bridging bonds act as electron transport channels to enable improved conductivity and accelerated reaction kinetics. The expanded interlayer‐spacing of ReSe2 layer by INC facilitates ion diffusion and ensures structural stability. As expected, the E‐ReSe2@INC achieves an improved rate capability (252.5 mAh g−1 at 20 A g−1) and long‐term cyclability (89.6% over 3500 cycles). Moreover, theoretical simulations reveal the favorable Na+ storage kinetics can be ascribed to its low bonding energy of −0.06 eV and diffusion barrier of 0.08 eV for sodium ions. Additionally, it is demonstrated that 3D printed sodium‐ion hybrid capacitors deliver high energies/power densities of 81.4 Wh kg−1/0.32 mWh cm−2 and 9992.1 W kg−1/38.76 mW cm−2, as well as applicability in a wide temperature range. [ABSTRACT FROM AUTHOR]

Ammonia (NH 3 ) is a versatile and important compound with a wide range of uses, which is currently produced through the demanding Haber-Bosch process. Electrocatalytic nitrate reduction into ammonia (NRA) has recently emerged as a sustainable approach for NH 3 synthesis under ambient conditions. However, the NRA catalysis is a complex multistep electrochemical process with competitive hydrogen evolution reaction that usually results in poor selectivity and low yield rate for NH 3 synthesis. With maximum atom utilization and well-defined catalytic sites, single atom catalysts (SACs) display high activity, selectivity and stability toward various catalytic reactions. Very recently, a number of SACs have been developed as promising NRA electrocatalysts, but systematical discussion about the key factors that affect their NRA performance is not yet to be summarized to date. This review focuses on the latest breakthroughs of SACs toward NRA catalysis, including catalyst preparation, catalyst characterization and theoretical insights. Moreover, the challenges and opportunities for improving the NRA performance of SACs are discussed, with an aim to achieve further advancement in developing high-performance SACs for efficient NH 3 synthesis., (© 2024 IOP Publishing Ltd.)