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[Display omitted] • A 3D soft-rigid PVDF@SnO 2 nanofiber layer is electrospun on copper current collector. • The soft nanofiber layers realize uniform Li+ flux and dendrite-free Li deposition. • Rigid SnO 2 offers abundant Li+ nucleation sites and promotes highly stable SEI layer. • Nanofiber flexible skeleton can accommodate and mitigate electrode volume expansion. • Such soft-rigid nanofiber layers account for prolonged cycle life of Li metal cells. Lithium (Li) metal is regarded as the most desirable anode candidates for high-energy–density batteries by virtue of its lowest redox potential and ultrahigh theoretical specific capacity. However, uncontrollable Li dendritic growth, infinite volume variation and unstable solid electrolyte interface (SEI) ineluctably plague its commercialization process. Herein, the three-dimensional (3D) nanofiber functional layers with synergistic soft-rigid feature, consisting of tin oxide (SnO 2)-anchored polyvinylidene fluoride (PVDF) nanofibers, are directly electrospun on copper current collector. This strategy can effectively regulate uniform Li deposition and strengthen SEI stability through the dual effect of physical accommodation and chemical ionic intervention. On the one hand, the nanofiber interlayers with excellent electrolyte affinity and well-distributed Li+ transport pathways can promote uniform Li+ flux distribution and large-size Li deposition. On the other hand, the rigid SnO 2 contributes to reducing Li nucleation overpotential and stabilizing SEI layer assisted by its spontaneous reaction with Li. As a result, the smooth and dense Li deposition is achieved by such soft-rigid nanofiber interlayers, thereby extending the cycling life and improving the safety application of Li metal batteries. This work offers a new route for efficient protection of Li metal anodes and brings a new inspiration for developing high-energy–density Li metal batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Fabricating a high-performance adsorbent as a desirable candidate for removing Pb2+ from aqueous water remains a challenge. Aramid nanofibers (ANFs) are promising building blocks that have realized multifunctional applications due to their intrinsic mechanical and chemical stability. Herein, an in situ loading strategy for preparing nanofiber composite aerogel was proposed by assembling ANFs into a 3D aerogel and applying it as host media for the in situ polymerization of pyrrole followed by facile redox reaction between the polypyrrole (PPy) and MnO 4 –1 to load manganese dioxide (MnO 2). The idea was to fully exploit the structural advantages of ultra-low bulk density, large specific surface area, and high porosity of ANFs, and the possible chemical adsorption characteristics of MnO 2 on the basis of ion exchange reaction. The adsorption capacity of 3D ANF/MnO 2 composite aerogel was as large as 554.36 mg/g for Pb2+. The adsorption mechanism based on an exchange reaction between Pb2+ and protons on the surface of MnO 2 was also investigated. The desorption results showed that the adsorption performance could remain up to 90% after five times of usage. In conclusion, this research provides promising insights into the preparation of high-performance lead adsorbent for water treatment. [ABSTRACT FROM AUTHOR]