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Ambient-temperature sodium-sulfur (Na-S) batteries are considered a promising energy storage system due to their high theoretical energy density and low costs. However, great challenges remain in achieving a high rechargeable capacity and long cycle life. Herein we report a stable quasi-solid-state Na-S battery enabled by a poly(S-pentaerythritol tetraacrylate (PETEA))-based cathode and a (PETEA-tris[2-(acryloyloxy)ethyl] isocyanurate (THEICTA))-based gel polymer electrolyte. The polymeric sulfur electrode strongly anchors sulfur through chemical binding and inhibits the shuttle effect. Meanwhile, the in situ formed polymer electrolyte with high ionic conductivity and enhanced safety successfully stabilizes the Na anode/electrolyte interface, and simultaneously immobilizes soluble Na polysulfides. The as-developed quasi-solid-state Na-S cells exhibit a high reversible capacity of 877 mA h g at 0.1 C and an extended cycling stability.

Holey tungsten oxynitride nanowires with superior conductivity, good biocompatibility, and good stability achieve excellent performance as anodes for both asymmetric supercapacitors and microbial fuel cells. Moreover, an innovative system is devised based on these as-prepared tungsten oxynitride anodes, which can simultaneously realize both energy conversion from chemical to electric energy and its storage.

With the development of portable electronic equipment, electric vehicle, space technology, and power‐grid and energy‐storage technology, new efficient energy‐storage devices need to be developed urgently. Recently, asymmetric supercapacitors (ASCs) have attracted ever‐increasing interest as one of the most promising energy‐storage devices given their remarkable advantages of wide operation voltage window, high power density, and moderate energy density. However, to meet the needs of the rapid development of electronic equipment, it is necessary to optimize the electrode materials and device design to further boost the energy density of ASCs. In recent years, numerous attempts have been made to improve the energy density of ASC devices by increasing the capacitance and/or enlarging the voltage window. Here, recent smart strategies are highlighted, including the introduction of intrinsic defects, element doping, and surface functionalization to increase the capacitance of the electrode materials, and optimizing the electrolyte and electrode materials, as well as their surface charge, to broaden the voltage of cells. Moreover, the current challenges and future opportunities for the development of high‐performance ASCs are also discussed.

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Two-dimensional (2D) hexagonal boron nitride (h-BN) is one of the most promising materials for many technological applications ranging from optics to electronics. In past years, a property-tunable strategy that involves the construction of electronic structures of h-BN through an atomic-level design of point defects has been in vogue. The point defects imported during material synthesis or functionalization by defect engineering can endow h-BN with new physical characteristics and applications. In this Perspective, we survey the current state of the art in multifunction variations induced by point defects for 2D h-BN. We begin with an introduction of the band structure and electronic property of the pristine h-BN. Subsequently, the formation and characterization of the most obvious point defects and their modulation in electronic structures of h-BN nanomaterials are envisaged in theory. The experimental results obtained by atom-resolved transmission electron microscopy, magnetic measurement, and optical measurements have provided insights into the point defect engineered structures and their corresponding emerging properties. Finally, we highlight the perspectives of h-BN nanomaterials for heterostructures and devices. This Perspective provides a landscape of the point defect physics involved to demonstrate the modulation of the structure and functionalities in h-BN and identify the roadmap for heterostructure and device applications, which will make advances in electronics, spintronics, and nanophotonics.