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Lithium–sulfur batteries (LSBs) are regarded as promising next‐generation energy storage systems owing to their remarkable theoretical energy density (2600 Wh kg‐1) and low cost. However, sluggish electrochemical kinetics, lithium polysulfides (LiPS) shuttling, and uncontrollable Li dendrite growth seriously hamper the commercial application of LSBs. Herein, dual‐functional 3D interconnected free‐standing fibers embedded with TiO2‐TiN heterostructures as an advanced skeleton are designed for concurrently regulating both the sulfur cathode (S/hollow TiO2‐TiN) and Li anode (Li/solid TiO2‐TiN). As a cathode skeleton, the hollow TiO2‐TiN fibers afford synergistic functions of chemical anchoring, physical confinement, and excellent electrocatalysis for LiPS. Meanwhile, the multifunctional skeleton with remarkable lithiophilicity and high conductivity can accomplish uniform Li deposition and homogeneous Li ion flux for inhibiting the growth of dendrites. Benefiting from these advantages, the full battery (S/hollow TiO2‐TiN || Li/solid TiO2‐TiN) exhibits excellent electrochemical performance, including high cycling stability (988.8 mAh g−1 after 200 cycles at 0.5 C) and impressive rate properties (639.3 mAh g−1 at 2 C). This work inaugurates a novel strategy from experimental and theoretical aspects for fabricating LSBs with robust electrochemical performance. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable zinc–metal batteries are a promising candidate for next‐generation energy storage devices due to their intrinsic high capacity, low cost, and high safety. However, uncontrollable dendrite formation is a serious problem, resulting in limited lifespan and poor coulombic efficiency of zinc–metal anodes. To address these issues, a 3D porous hollow fiber scaffold with well‐dispersed TiO2, SiO2, and carbon is used as superzincophilic host materials for zinc anodes. The amorphous TiO2 and SiO2 allow for controllable nucleation and deposition of metal Zn inside the porous hollow fiber even at ultrahigh current densities. Furthermore, the as‐fabricated interconnected conductive hollow SiO2 and TiO2 fiber (HSTF) possess high porosity, high conductivity, and fast ion transport. Meanwhile, the HSTF exhibits remarkable mechanical strength to sustain massive Zn loading during repeated cycles of plating/stripping. The HSTF with interconnected conductive network can build a uniform electric field, redistributing the Zn2+ ion flux and resulting in smooth and stable Zn deposition. As a result, in symmetrical cells, the Zn@HSTF electrode delivers a long cycle life of over 2000 cycles at 20 mA cm−2 with low overpotential (≈160 mV). The excellent cycling lifespan and low polarization are also realized in Zn@HSTF//MnO2 full cells. [ABSTRACT FROM AUTHOR]

As a conventional insulating material, boron nitride (BN) has been mainly investigated in the electronics field. Very recently, with the development of preparation/modification technology and deeper understanding of the electrochemical mechanisms, BN‐based nanomaterials have made significant progress in the field of electrochemistry. Exploiting the characteristics of BN for advanced electrochemical devices is expected to be a breakthrough that will stimulate a new energy revolution. Owing to its chemical and thermal stability, as well as its high mechanical strength, BN can alleviate various inherent problems in electrochemical systems, such as thermal deformation of conventional organic separators, weak solid electrolyte interface layers of metal anodes, and electrocatalyst poisoning. The integration of BN with various electrochemical energy technologies is systematically summarized from the perspectives of material preparation, theoretical calculations, and practical applications. Moreover, the challenges and prospects for the future development of BN‐based electrochemistry are highlighted. [ABSTRACT FROM AUTHOR]

Aqueous zinc–iodine batteries show immense potential in the electrochemical energy storage field due to their intrinsic safety and cost‐effectiveness. However, the rampant dendritic growth and continuous side reactions on the zinc anode, coupled with the shuttling phenomenon of polyiodides, severely affect their cyclic life. In response, this study utilizes a carboxyl‐functionalized metal‐organic framework UiO‐66‐(COOH)2 (UC) to modify commercial glass fiber (GF) to develop a novel ionic selective separator (UC/GF). This separator exhibits cation exchange ability for Zn2+ and polyiodides, thereby simultaneously stabilizing the zinc anode and inhibiting the shuttle effect of polyiodides. Enhanced by the abundant polar carboxyl groups, the UC/GF separator can effectively facilitate Zn2+ ion transport and accelerate the desolvation of hydrated zinc ions by its zincophilicity and hydrophilicity, while significantly hindering the transfer of polyiodides via electrostatic repulsion. Consequently, the Zn|UC/GF|Zn symmetric battery enables a long lifespan of over 3400 h at a current density of 5.0 mA cm−2, while the Zn|UC/GF|I2 exhibits an exceptional discharge capacity of 103.8 mAh g−1 after 35 000 cycles at 10 C with a capacity decay rate of only 0.0013% per cycle. This separator modification strategy that synergistically optimizes anode and cathode performance provides unique insights into the commercialization of zinc–iodine batteries. [ABSTRACT FROM AUTHOR]