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Aerogels with ultrahigh porosity and large specific surface area have demonstrated great potential for capturing volatile organic compounds (VOCs). Especially, aerogel fiber aggregates with macropores formed by overlapping aerogel fibers and mesopores in the aerogel fibers might realize fast sorption kinetics and high sorption capacity simultaneously. However, how to develop fast fabrication and large‐scale production of aerogel fibers remains a challenge. Herein, a generic sol‐gel centrifugal spinning (SCS) strategy with a spinning rate capable of reaching 700 m min−1 is developed for producing aerogel fibers. The representative SCS aerogel fiber made from aramid nanofiber (ANF) dispersion exhibits a large specific surface area (313 m2 g−1) and high tensile strength (12.48 MPa). The SCS strategy is further applied to fabricate various kinds of aerogel fibers, including sodium alginate, cellulose, and chitosan. The ANF aerogel fiber aggregates exhibit superior VOC adsorption capacity of 438.0 mg g−1 under an ultrafast gas flux of 3.8 × 104 L m−2 h−1, which also has satisfactory cyclic stability. This work not only develops a powerful and generic strategy for fabricating aerogel fibers in large scale, but also provides inspiration for applying these SCS aerogel fibers in dynamic removal of VOCs and other environmental protection fields. [ABSTRACT FROM AUTHOR]

Nanoporous aerogel fibers enjoy the luxury of being one of the most attractive nanomaterials. However, the representative fabrication pathways have faced up with low production rates due to significant speed mismatch between slow sol–gel transition and as fast as possible spinning in the same period. Herein, a novel gas‐blows‐liquid spinning (GS) strategy with a spinning speed of 300–700 m s−1 is developed to get the high‐speed and high‐efficiency production of aerogel fibers/fabrics. The spinning speed of the GS strategy is 900 times higher than various techniques reported for aerogel fibers. The resulting aerogel fibers exhibit a high specific surface area (180 m2 g−1). In comparison, the aerogel fiber possesses the highest tensile strength (58.7±3.9 MPa) among its counterparts and aerogel fabric with surprising water‐absorption and microparticle‐blocking performances exhibits the application prospect for better hemostasis than that of commercial gauze and cotton ball. Besides, the GS aerogel fabrics with hierarchical aligned structures show better thermal insulation (≈0.035 Wm−1K−1) than wet spinning aerogel fabric and commercial insulation felts. This work has provided inspiration for fast fabricating more aerogel fibers/fabrics with this GS strategy, and the resulting aerogel fibers/fabrics may find significant application in the fields of 5G smart phones, wound hemostasis, etc. [ABSTRACT FROM AUTHOR]

Solid–liquid composite materials that confine a functional liquid within a porous solid have appeared in a wealth of emerging applications. However, creating dynamic liquid interfaces for efficient ion capture while stably retaining functional liquid in porous confinements is challenging. Here, an aerogel‐confined liquid‐based composite membrane (ALCM) for dynamic and highly efficient uranium capture is reported. As a proof of concept, Kevlar aerogel membrane is selected as the nanoporous solid, and calix[6]arene/tributyl phosphate (C6/TBP) is used as the guest liquid. The obtained ALCMs possess high stability, optimum adhesion between solid‐liquid interface, and high selectivity for uranyl ions (250–6510 times over other competing ions). Different dynamic interface regulating approaches are explored for ALCMs, and uranium extraction efficiency under alternating pressures can be up to 258.48 mg g−1 h−1, outperforming many reported uranium capture materials. This strategy can be applicable to develop a rich family of solid‐liquid composite materials and may spearhead a new paradigm for uranium capture from sustainable seawater resources. [ABSTRACT FROM AUTHOR]

Transparent silica aerogel, serving as one typical porous and transparent material, possesses various unique features (e. g. large amounts of pores and interfaces, super‐lightweight, super thermal insulation, low refractive index similar to gas), and it has attracted great attention in the fields of science, technology, engineering, art, and others. Transparency is one important evaluation index of transparent silica aerogel, and it was influenced by various factors such as raw materials, sol‐gel reactions, phase separation, and drying methods. The structure design and fabrication of transparent silica aerogel is one huge and fine engineering. In this review, the optical/chemical guidance and design for the preparation of transparent silica aerogels are discussed, and typical applications, such as Cherenkov detectors, solar energy collection, lighting systems, and transparent fabric, were also discussed. Finally, a future outlook on the opportunities and challenges of transparent silica aerogels was proposed. [ABSTRACT FROM AUTHOR]

Wood‐decay macrofungi play a vital role in forest ecosystems by promoting nutrient cycling and soil structure, and their evolution is closely related to their host plants. This study investigates the potential evolutionary adaptation of wood‐decay macrofungi to their host plants, focusing on whether these relationships differ between gymnosperms and angiosperms. While previous research has suggested non‐random associations between specific fungi and plant deadwood, direct evidence of evolutionary adaptation has been lacking. Our study, conducted in a subtropical region, utilized metabarcoding techniques to identify deadwood species and associated fungi. We found significant evidence of evolutionary adaptation when considering all sampled species collectively. However, distinct patterns emerged when comparing angiosperms and gymnosperms: a significant evolutionary adaptation was observed of wood‐decay macrofungi to angiosperms, but not to gymnosperms. This variation may be due to the longer evolutionary history and more stable species interactions of gymnosperms, as indicated by a higher modularity coefficient (r =.452), suggesting greater specialization. In contrast, angiosperms, being evolutionarily younger, displayed less stable and more coevolving interactions with fungi, reflected in a lower modularity coefficient (r =.387). Our findings provide the first direct evidence of differential evolutionary adaptation dynamics of these fungi to angiosperms versus gymnosperms, enhancing our understanding of forest ecosystem carbon cycling and resource management. [ABSTRACT FROM AUTHOR]

Porous liquids (PLs), porous materials with flowable states, show promising applications in some emerging fields. However, creating porous materials with on-demand flowability is still significantly challenging. Herein, aerogel-based stimulus-responsive porous liquids have been proposed and fabricated via dispersing superhydrophobic silica aerogel microparticles in a polymer aqueous solution with either lower or upper critical solution temperature (LCST or UCST), respectively. The resulting aerogel-based intelligent porous liquids possess quite low density (0.56 g cm−3), high porosity (up to 48.57%), low thermal conductivity (0.239 W m−1 K−1) and appropriate viscosity (4.1–220.6 Pa s). Most importantly, the resulting porous liquids show reversible thermal responsiveness. Thus, a new condensed state, i.e., solid–liquid–vapor triple-state gels, might be obtained via on-demand thermal triggering of these aerogel-based porous liquids. Cut triple-state gels show interesting self-healing behaviors via either thermal treatment or replenishment of a small extra amount of porous liquids. To our surprise, the reversible transition between aerogel-based flowable porous liquids and solid–liquid–vapor triple-state non-flowable gels has endowed these materials with plastic-like processing capability upon demand. These porous liquids, together with those triple-state gels, might find broad applications in some emerging fields, and the work reported here might inspire scientists to fabricate more aerogel-based porous liquids and triple-state gels. [ABSTRACT FROM AUTHOR]

Boron nitride (BN) aerogels, dual interconnecting network of BN nanoscale building blocks, and plenty of air within these nanoscale building blocks, have great potential in many emerging fields. However, fast synthesis and emerging applications, e.g., information encryption, are still challenging for advancing BN aerogels. Herein, intrinsic photoluminescent BN aerogels with programmable patterns are developed via laser ablating of melamine diborate (M2B) aerogel. The obtained BN aerogel exhibited typical hollow‐microsphere structures and blue fluorescence phenomenon, which are totally different from BN aerogels reported elsewhere. This BN aerogel exhibited excellent thermal insulation properties (0.027 W mK−1), transient fluorescence feature (3 ns average radiative lifetime), high quantum yield (18.45%), and excellent weather ability (e.g., resistance to high temperature, solar irradiation, and humidness). By programming the laser moving path, different fluorescent patterns (e.g., various security labels, secret matching keys, quick response codes) of BN aerogels can be processed, which promises excellent information encryption in the field of Internet of Things, etc. The results may inspire researchers to fabricate more aerogels with this fast laser‐ablation strategy and the resulting intrinsic fluorescent BN aerogels may find significant applications in some emerging fields. [ABSTRACT FROM AUTHOR]

Gas channeling control is key to improving CO2-flooding efficiency. A traditional plugging system has disadvantages, such as poor adaptability and stability, leading to the poor plugging effect of CO2 channeling in heterogeneous reservoirs and difficulty in controlling the subsequent CO2 injection pressure. To achieve a significant plugging effect and effectively control the subsequent CO2 injection pressure, a heterogeneous physical model of gas channeling in a horizontal well was established, and plugging experiments were conducted using four different combinations of plugging agents during CO2 flooding. Three evaluation parameters were defined, including the temperature field variation coefficient (TFVC), medium-permeability diversion rate (MPDR), and subsequent injection pressure coefficient (SIPC). The plugging effect of different combinations of plugging agents during CO2 flooding in heterogeneous reservoirs was analyzed. The results show that the plugging effect after using a combination of plugging agents was significantly better than after using a single plugging agent, and different plugging agent combinations had distinct characteristics. The strong–medium–weak (S-M-W) combination had the best MPDR for subsequent CO2 flooding, but the SIPC was the highest. The strong–weak–strong–weak (S-W-S-W) and weak–strong–weak–strong (W-S-W-S) combinations could effectively control the SIPC. These results indicate that plugging using the S-W-S-W and W-S-W-S combinations can achieve an effective plugging effect and reasonably control the subsequent CO2 injection pressure. This work provides a personalized design scheme for effective gas channeling control and maintenance of appropriate injection pressure during CO2 flooding in heterogeneous reservoirs. [ABSTRACT FROM AUTHOR]

Graphene aerogel (GA) samples, prepared by the Sol-Gel method, were tested under quasi-static and dynamical compression, and characterized via surface area analyzer and scanning electron microscopy. The results show that the drying method has a significant influence on the sample’s microstructure as well as its mechanical compression properties. The supercritical CO2 dried sample has a notable higher specific surface area, and higher compression strength; although the freeze dried sample is much lighter than the supercritical CO2 dried sample, it exhibits a nonlinear superelastic behavior and large compressibility with a reversible strain up to 94%; under the dynamic compression test, the supercritical CO2 dried sample presents a negative Poisson’s ratio behavior whereas the flower-like failure pattern was observed for the freeze dried sample. GA, therefore, is a promising candidate for energy absorption purposes because of its very low density, high specific surface area and porous microstructure.

Aerogels are ultralight solid materials with three‐dimensional interconnected porous structures that offer considerable advantages for various protective applications. Lasers have led to various technological revolutions in aerospace, medical science, and industrial manufacturing. However, shielding against high‐energy laser irradiation using aerogels has rarely been reported. A super‐white (reflectivity >98%) boron nitride (BN) aerogel constructed using BN nanoribbons is developed in this study for high‐energy laser protection. Large numbers of BN nanoribbons serve as randomized and disordered optical nanobarriers for intense backlight scattering, which contribute to high broadband reflectivity. Combined with the low thermal conductivity of the aerogel structure and the excellent high‐temperature stability of BN, the resulting BN aerogel exhibits a high protective threshold of 2.1 × 104 W cm−2. Moreover, the BN aerogel possesses a soft porous network and a low thermal expansion coefficient, which is promising for tolerating the thermal stress and shock of local high‐temperature fields caused by laser irradiation. The successful laser shielding by the super‐white BN aerogel may be helpful for designing and fabricating advanced aerogel‐based lightweight anti‐laser materials. [ABSTRACT FROM AUTHOR]