Developing a feasible and efficient separation membrane for the purification of highly emulsified oily wastewater is of significance but challenging due to the critical limitations of low flux and serious membrane fouling. Herein, a biomimetic and superwettable nanofibrous skin on an electrospun fibrous membrane via a facile strategy of synchronous electrospraying and electrospinning is created. The obtained nanofibrous skin possesses a lotus‐leaf‐like micro/nanostructured surface with intriguing superhydrophilicity and underwater superoleophobicity, which are due to the synergistic effect of the hierarchical roughness and hydrophilic polymeric matrix. The ultrathin, high porosity, sub‐micrometer porous skin layer results in the composite nanofibrous membranes exhibiting superior performances for separating both highly emulsified surfactant‐free and surfactant‐stabilized oil‐in‐water emulsions. An ultrahigh permeation flux of up to 5152 L m−2 h−1 with a separation efficiency of >99.93% is obtained solely under the driving of gravity (≈1 kPa), which was one order of magnitude higher than that of conventional filtration membranes with similar separation properties, showing significant applicability for energy‐saving filtration. Moreover, with the advantage of an excellent antioil fouling property, the membrane exhibits robust reusability for long‐term separation, which is promising for large‐scale oily wastewater remediation.

Traffic noise pollution has posed a huge burden to the global economy, ecological environment and human health. However, most present traffic noise reduction materials suffer from a narrow absorbing band, large weight and poor temperature resistance. Here, we demonstrate a facile strategy to create flexible ceramic nanofibrous sponges (FCNSs) with hierarchically entangled graphene networks, which integrate unique hierarchical structures of opened cells, closed-cell walls and entangled networks. Under the precondition of independent of chemical crosslinking, high enhancement in buckling and compression performances of FCNSs is achieved by forming hierarchically entangled structures in all three-dimensional space. Moreover, the FCNSs show enhanced broadband noise absorption performance (noise reduction coefficient of 0.56 in 63–6300 Hz) and lightweight feature (9.3 mg cm–3), together with robust temperature-invariant stability from –100 to 500 °C. This strategy paves the way for the design of advanced fibrous materials for highly efficient noise absorption.

Creating a porous membrane to effectively separate the emulsified oil-in-water emulsions with energy-saving property is highly desired but remains a challenge. Herein, a multilayer nanofibrous membrane was developed with the inspiration of the natural architectures of earth for gravity-driven water purification. As a result, the obtained biomimetic multilayer nanofibrous membranes exhibited three individual layers with designed functions; they were the inorganic nanofibrous layer to block the serious intrusion of oil to prevent the destructive fouling of the polymeric matrix; the submicron porous layer with designed honeycomb-like cavities to catch the smaller oil droplets and ensures a satisfactory water permeability; and the high porous fibrous substrate with larger pore size provided a template support and allows water to pass through quickly. Consequently, with the cooperation of these three functional layers, the resultant composite membrane possessed superior anti-oil-fouling property and robust oil-in-water emulsion separation performance with good separation efficiency and competitive permeation flux solely under the drive of gravity. The permeation flux of the membrane for the emulsion was up to 5163 L m h with a separation efficiency of 99.5%. We anticipate that our strategy could provide a facile route for developing a new generation of specific membranes for oily wastewater remediation.

Traffic noise is a major source of urban noise pollution, with severe threats to the physiological and psychological health of humans. Fibrous sound absorption materials are extensively applied in the control of traffic noise pollution; however, the larger fiber diameters and monotonous internal structure of such materials result in poor low‐frequency sound‐absorbing properties or unsatisfied mechanical properties. Herein, a biomimetic and robust strategy to design ultrastrong and superelastic fibrous sound absorption sponges is reported, which is achieved by integrating a one‐step forming technique of interlocked micro/nano dual fiber networks and an in situ crosslinking approach. The obtained vine‐like interlocked structured fibrous sponges can withstand a tensile force 10 000 times their weight without deformation. Furthermore, the materials also show outstanding compression fatigue resistance and a lightweight feature (8.70 mg cm−3). Most importantly, the interlocked dual‐network‐induced stable fluffy‐stacked structure endows the fibrous sponges with an enhanced low‐frequency sound‐absorbing property (absorption coefficient of 0.93 at 1000 Hz), which is superior to those of commercial and reported sound absorption materials. In addition, the materials also possess good hydrophobicity and temperature resistance. This work opens new pathways for the further development of highly efficient sound‐absorbing materials.

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