Micro‐supercapacitors are notorious for their low energy densities compared to micro‐batteries. While MXenes have been identified as promising capacitor‐type electrode materials for alternative zinc‐ion hybrid micro‐supercapacitors (ZHMSCs) with higher energy density, their tightly spaced layered structure renders multivalent zinc‐ions with large radii intercalation inefficient. Herein, through insertion of 1D core‐shell conductive BC@PPy nanofibers between MXene nanosheets, an interlayer structure engineering technique for MXene/BC@PPy capacitor‐type electrodes towards ZHMSCs is presented. Owing to simultaneously achieving two objectives: (i) widening the interlayer space and (ii) providing conductive connections between the loose MXene layers, enabled by the conductive BC@PPy nanospacer, the approach effectively enhances both ion and electron transport within the layered MXene structure, significantly increasing the areal capacitance of the MXene/BC@PPy film electrode to 388 mF cm−2, which is a 10‐fold improvement from the pure MXene film electrode. Pairing with CNTs/MnO2 battery‐type electrodes, the obtained ZHMSCs exhibit an areal energy density up to 145.4 μWh cm−2 with an outstanding 95.8% capacity retention after 25000 cycles, which is the highest among recently reported MXene‐based MSCs and approaches the level of micro‐batteries. The interlayer structure engineering demonstrated in the MXene‐based capacitor‐type electrode provides a rational means to achieve battery‐levelenergy density in the ZHMSCs.

Tip-induced dendrites on metallic zinc anodes (MZAs) fundamentally deteriorate the rechargeability of aqueous Zn metal batteries (ZMBs). Herein, an intriguing ion sieve (IS) consisting of 3D intertwined bacterial cellulose, deposited on the surface of MZAs (Zn@IS) through an in situ self-assembly route, is first presented to be effective in inhibiting dendrite-growth on MZAs. Experimental analyses together with theoretical calculations suggested that the IS coating can facilitate the desolvation of [Zn­(H2O)6]2+ clusters via a strong interplay with Zn ions, weaken hydrogen evolution reaction of MZAs, and homogenize the ion flux with the abundant nanopores serving as ion tunnels, synergistically enabling dendrite-free Zn deposition on the Zn@IS anodes. Consequently, a lifespan up to 3000 h at a cutoff capacity of 0.25 mA h cm–2 was observed in a Zn@IS∥Zn@IS symmetric cell. In terms of application, pairing with a carbon-nanotube@MnO2 cathode as an example, the full ZMBs acquired enhanced rechargeability with much higher capacity retention over 73.3% after 3000 cycles compared to the counterpart with pristine MZA (21%).

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Biofouling refers to the unfavourable attachment and accumulation of marine sessile organisms (e.g. barnacles, mussels and tubeworms) on the solid surfaces immerged in ocean. The enormous economic loss caused by biofouling in combination with the severe environmental impacts induced by the current antifouling approaches entails the development of novel antifouling strategies with least environmental impact. Inspired by the superior antifouling performance of the leaves of mangrove tree , here we propose to combat biofouling by using a surface with microscopic ridge-like morphology. Settlement tests with tubeworm larvae on polymeric replicas of leaves confirm that the microscopic ridge-like surface morphology can effectively prevent biofouling. A contact mechanics-based model is then established to quantify the dependence of tubeworm settlement on the structural features of the microscopic ridge-like morphology, giving rise to theoretical guidelines to optimize the morphology for better antifouling performance. Under the direction of the obtained guidelines, a synthetic surface with microscopic ridge-like morphology is developed, exhibiting antifouling performance comparable to that of the replica. Our results not only reveal the underlying mechanism accounting for the superior antifouling property of the leaves, but also provide applicable guidance for the development of synthetic antifouling surfaces.

In recent years, the textile industry has been seeking to develop innovative products. It is a good choice to organically combine materials with superior functional characteristics and commercial textiles to form products with excellent performance. In particular, textiles made of biological functional materials are often beneficial to human health, which is an interesting research direction. As a biopolymer material, chitosan has the advantages of strong availability, low cost, excellent safety, outstanding performance, etc., particularly the antibacterial property, and has broad application prospects in the textile field. This review provides an overview of the latest literature and summarizes recent innovations and state-of-the-art technologies that can add value to textiles. To this end, preparation of chitosan fiber, synthesis of chitosan nanofiber, antibacterial activity of chitosan fiber, antibacterial activity of chitosan nanofiber, etc., will be discussed. Furthermore, the challenges and prospects of chitosan-based materials used in textiles are evaluated. Importantly, this review can not only help researchers understand the development status of antibacterial textiles, but also help researchers discover and solve problems in this field through comparative reading.

Famous for high theoretical energy density (≈1086 Wh kg −1 ), five time that of dominant lithium ion batteries (LIBs), the recently developed flexible solid-state Zn-air batteries (FSZABs)

Developing conductive underwater glue for fast sealing and in situ monitoring is critical for ocean exploration yet remains a challenge. The fluidity of glue is a double‐edged sword that is favorable for molecule spreading and formation of interlocking bonding network yet also leads to leakage of conductive ions. Herein, a polymeric glue possessing good conductivity and exhibiting rapid, strong, and long‐lasting underwater adhesion on diverse substrates at various harsh environments and extreme temperatures is developed. For molecular design, the nitrogen heterocyclic motif that prevails in biomolecular recognition is encoded with water‐resistant benzene block in one pendant group to serve as underwater binding sites; ionic liquids (ILs) of [EMIM][BF4] is employed as the solvent for fast water exchange that triggers rapid adhesion. Simultaneously, the polymer‐IL interaction is regulated, with the assistance of the theoretical calculations, to retain sufficient ILs within the adhesive for sensing. Finally, the glue is applied for underwater sealing and in situ monitoring various physical signals, while the fluorescent property is utilized for underwater labeling. This study should provide a new design strategy for the next‐generation of multifunctional underwater adhesives and promote their applications.

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