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The emerging solar desalination technology is considered as one of the most promising strategies to ensure water security. However, with the proceeding of solar desalination, salt crystallization on the surface of solar evaporators caused by increasing salinity of seawater will result in a decrease in the evaporation rate. Thus, it is still challenging to fabricate solar evaporators with superior salt resistance. In this work, elastic ceramic‐based nanofibrous aerogels with a cellular architecture are fabricated by the combination of electrospinning and fiber freeze‐shaping technologies, which are composed of vertically aligned vessels and porous vessel walls. Under the action of convection and diffusion promoted by this unique cellular architecture, the aerogels exhibit a superior salt‐resistance without any salt crystals on the surface of aerogels even in 20% brine and under 6‐sun irradiation. Moreover, by virtue of the synergistic effect of the promising structure and light absorbance of carbon nanotubes, aerogels possess a high light absorbance of up to 98% and excellent evaporation performance achieving 1.50 kg m−2 h−1 under 1‐sun irradiation. This work may provide a fascinating avenue for the desalination of seawater in a salt‐resistance and efficient manner.

Rational structural design involving controlled pore size, high porosity, and particle-targeted function is critical to the realization of highly efficient air filters, and the filter with absolute particle-screen ability has significant technological implications for applications including individual protection, industrial security, and environmental governance; however, it remains an ongoing challenge. In this study, we first report a facile and scalable strategy to fabricate the highly integrated polysulfone/polyacrylonitrile/polyamide-6 (PSU/PAN/PA-6) air filter for multilevel physical sieving airborne particles via sequential electrospinning. Our strategy causes the PSU microfiber (diameter of ∼1 μm) layer, PAN nanofiber (diameter of ∼200 nm) layer, and PA-6 nanonets (diameter of ∼20 nm) layer to orderly assemble into the integrated filter with gradually varied pore structures and high porosity and thus enables the filter to work efficiently by employing different layers to cut off penetration of particles with a certain size that exceeds the designed threshold level. By virtue of its elaborate gradient structure, robust hydrophobicity (WCA of ∼130°), and superior mechanical property (5.6 MPa), our PSU/PAN/PA-6 filter even can filtrate the 300 nm particles with a high removal efficiency of 99.992% and a low pressure drop of 118 Pa in the way of physical sieving manner, which completely gets rid of the negative impact from high airflow speed, electret failure, and high humidity. It is expected that our highly integrated filter has wider applications for filtration and separation and design of 3D functional structure in the future.

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.

Robust functional nanofibrous aerogels were designed by inserting lashing-structured scaffolds through a freeze-drying method.

Low-density 3D ultrafine fiber assemblies obtained from direct electrospinning enable promising applications in sound absorption fields but are often hindered by their poor structure stability. Here, we demonstrate an electrospun ultrafine fiber sponge with a microstructure-derived reversible elasticity and high sound absorption property, which is achieved by designing a hierarchical lamellar corrugated architecture that functioned as elastic units. The obtained electrospun fiber sponge can quickly recover to the original height even under the distortion from burdens 8900 times its weight. Particularly, the material can maintain its structural stability after 100 cycles at 60% strain. Moreover, the initial hierarchical structure and hydrophobicity of the prepared materials endow them with an ultralight property (density of 6.63 mg cm–3), superior low-frequency sound absorption, and excellent performance maintenance. The successful synthesis of these fascinating materials may provide new insights into the design of lightweight and efficient sound absorption materials.

Particulate matter (PM) has taken heavy tolls on the global economy and public health, calling for air filters that can remove PM from high‐temperature emission sources. However, creating desirable filter media capable of capturing polydisperse fine particles (PFPs) effectively and enduringly, while also withstanding high speed airstream, is extremely challenging. Here, a biomimetic and bottom‐up strategy to prepare superelastic, strong, and thermostable nanofibrous aerogels (NFAs) as cascade filters by assembling semi‐interpenetrating polymer network (semi‐IPN)‐based nanofibers into a gradient architecture is reported. Inspired by the robust loofah sponges originating from stiff cellulose networks, the mechanical property of NFAs is enhanced via tailoring the chain flexibility of heat‐resistant semi‐IPNs. Further constructing a gradient cellular architecture endows NFAs with a versatile cascade filtration behavior for capturing polydisperse fine particles. The resultant semi‐IPN‐based gradient NFAs exhibit temperature‐invariant superelasticity, a high compressive stress (7.9 kPa) and modulus (12 kPa), high filtration efficiency (>99.97%, PM0.3), low pressure drop (≈50% that of membranes), and ultrahigh dust‐holding capacity (114 g m−2). The fabrication of this attractive material paves the way for designing next‐generation air filters for industrial dust removal.

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