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Zn metal batteries have garnered considerable scientific and technological interests. However, the widespread commercial application of these batteries is impeded by the uncontrollable dendrite growth and consequent severe side effects. Herein, a functionalized separator is prepared by spraying polyaniline‐modified graphene oxide (denoted as NPGO)/polyvinylidene difluoride solution directly on one side of a common separator of glass fibers (GFs). The reversible transition between protonated and deprotonated states of quinolone imide on NPGO nanosheets can facilitate the rapid desolvation and transfer of Zn2+. Therefore, the spatial electric field as well as the Zn2+ flux is effectively homogenized due to the ion‐sieving effect of NPGO nanosheets that are oriented toward Zn anode. This engineering design of the NPGO@GFs separator harvests excellent rate and cycling performance (over 3000 cycles at 20 mA cm−2) for Zn metal symmetric batteries. Meanwhile, it provides an impressive commercial prospect (500 cycles with a capacity retention of 91.6% under 2000 mA g−1) for MnO2||Zn full batteries. Such a strategy can be generalized as a common way to protect metal anodes (Na, Zn, and K) in rechargeable batteries, which is highly cost‐effective and scalable. [ABSTRACT FROM AUTHOR]

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]

The construction of a heterointerface by structure-induced partial phase transformation is an effective strategy to synchronously boost conductivity and regulate the ion diffusion kinetics of TiO2 considered as an anode material for sodium ion batteries. However, construction of a highly conductive heterostructure in well-crystallized TiO2 is still a great challenge. Herein, a structure-induced partial phase transformation method is reported to synthesize hierarchical hollow TiO2/TiN heterostructure fibers (HTTFs) with a high specific surface area for use as an anode. The interfacial effect of the heterostructures for the anode materials could improve charge transfer capability. The improvement of the conductivity is due to the electric field generated inside the nanocrystals, which greatly reduces the ion diffusion resistance of nanocrystals and promotes the interfacial electron transport. Density functional theory calculations and experimental results demonstrate that HTTFs greatly facilitated the mobility of holes and ion diffusion, which result in excellent rate capability (270.9 and 113.1 mA h g−1 at 50 and 10 000 mA g−1, respectively) and excellent cycling stability (132.5 mA h g−1 with an average capacity fading of only 0.002% per cycle at 5000 mA g−1 over 10 000 cycles). Such improvements signify that suitable heterogeneous interface design provides an innovative and versatile approach for achieving advanced battery materials. [ABSTRACT FROM AUTHOR]

Multifunctional biocompatible scaffolds with enhanced osteogenic capacity coupled with magnetic and magnetothermal properties are of great interest for the repair of large bone defects resulting from the resection of tumors. In the present study, we created borosilicate bioactive glass (BG) scaffolds loaded with varying amounts (5–15 wt%) of Fe3O4 magnetic nanoparticles (MNPs) and evaluated their performance in vitro and in vivo. The incorporation of MNPs endowed scaffolds with excellent magnetic, controlled magnetothermal properties and higher mechanical capacity. The MNP-loaded scaffolds were not toxic to human bone marrow-derived stem cells (hBMSCs) cultured on the scaffolds in vitro. The alkaline phosphatase activity and the osteogenic gene expression of the hBMSCs increased with increasing amount of MNPs in the scaffolds. When implanted in rat calvarial defects for 8 weeks, the scaffolds loaded with 15 wt% MNPs showed a significantly better capacity to regenerate bone when compared to the scaffolds without the MNPs. These MNP-loaded BG scaffolds are promising implants for regenerating bone in defects resulting from tumor resection. [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]

Multifunctional biocompatible scaffolds with enhanced osteogenic capacity coupled with magnetic and magnetothermal properties are of great interest for the repair of large bone defects resulting from the resection of tumors. In the present study, we created borosilicate bioactive glass (BG) scaffolds loaded with varying amounts (5-15 wt%) of Fe 3 O 4 magnetic nanoparticles (MNPs) and evaluated their performance in vitro and in vivo. The incorporation of MNPs endowed scaffolds with excellent magnetic, controlled magnetothermal properties and higher mechanical capacity. The MNP-loaded scaffolds were not toxic to human bone marrow-derived stem cells (hBMSCs) cultured on the scaffolds in vitro. The alkaline phosphatase activity and the osteogenic gene expression of the hBMSCs increased with increasing amount of MNPs in the scaffolds. When implanted in rat calvarial defects for 8 weeks, the scaffolds loaded with 15 wt% MNPs showed a significantly better capacity to regenerate bone when compared to the scaffolds without the MNPs. These MNP-loaded BG scaffolds are promising implants for regenerating bone in defects resulting from tumor resection.