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Ceramic nanofibrous aerogels have attracted great interest because of their extraordinary multifunctional properties. Herein, a facile strategy was proposed to create SiO 2 nanofibers-BN nanoribbons assembled binary aerogel with excellent temperature-invariant super-flexibility, as well as low thermal conductivity, low infrared radiation and excellent sound absorption properties. In addition, the unique structure of the nanofibers-nanoribbon aerogel acts as the thermal insulation layer, combined with Al foil acting as an infrared reflection layer, forming a component that can effectively hide high infrared targets. The nanofibrous-nanoribbons binary aerogel possess low thermal conductivity (0.0288 W/(m⋅K)) and outstanding sound-absorption ability (NRC value of 0.43), as well as excellent infrared stealth ability, which makes it an ideal candidate for thermal insulation and sound absorption in multi fields. [ABSTRACT FROM AUTHOR]

Herein, a novel flexible SiO 2 aerogel composite nanofiber membrane with strawberry-like structure and excellent thermal insulation properties, in which SiO 2 aerogel particles act as thermal insulation filler, was prepared by electrospinning technology. With the addition of nano-pore structure SiO 2 aerogel particles, the heat transfer path of the fibers inside the membrane became discontinuous, endowing the as-prepared membrane an ultra-low thermal conductivity of 30.3 mW/(m⋅K) and large surface area of 240 m2/g. Moreover, the nanofibers membrane also possesses the combined merits of excellent fire resistance, high-temperature stability, and temperature-invariant flexibility, rendering it a promising in the application of insulation and gas adsorption. The successful preparation of this flexible nanofiber membrane paves a new way to design materials with excellent thermal insulation and adsorption properties. [ABSTRACT FROM AUTHOR]

Environmental noise has been regarded as major noise pollution with severe hazards to human physical and mental health. The common commercial fiber sound-absorption materials have insufficient low frequencies wave absorbing and fire-resistant ability, limiting their wide application. To solve these problems, a novel strategy combining flexible nanofibers and rGO/MXene nanosheets was proposed to fabricate rGO/MXene/SiO 2 nanofibers composite aerogel with hierarchically porous structure, which possessed an extremely low density of 9.8 mg/cm3 and superior low-frequency sound absorption ability (NRC value of 0.51). The obtained composite aerogel possessed a large deformation up to 80% (corresponding compressive stress of 17 kPa) and quickly recovered. In addition, the as-prepared aerogel could be easily produced on a large scale, providing a reference for the development of new generation of sound-absorbing products. [ABSTRACT FROM AUTHOR]

Nanofibrous aerogel composites have emerged as most promising materials for their high-temperature insulation in complex environments due to their ultra lightweight, high elasticity, and superior thermal performance. However, the release of particles caused by weak bond strength between nanofibers and aerogel, lead to insulation failure which presents serious challenge. This research presents, a novel approach to mitigate the particle release and significantly improve the overall performance of nanofibrous aerogel composites. The proposed method involves the preparation of particle-free nanofibrous aerogel composites through unique combination of sol-aerogel blending, electrospinning, and freeze-casting processes. The effect of particle release has been successfully eliminated by embedding TiO 2 aerogel within SiO 2 nanofibers even under rigorous conditions (weight loss rate less than 0.57%). Furthermore, the resulting nanofibrous aerogel composite exhibits exceptional thermal insulation properties, with a low thermal conductivity of 0.0251 W/mK at room temperature. Additionally, the proposed composite material configuration demonstrates superior infrared radiation suppression performance resulting in an infrared transmittance of 39.52%. The lamellar structure of the nanofibers aerogel is tailored to provide high compressive strength (2.2 kPa at 40% strain), exceptional cyclic fatigue resistance after 50 cycles, and temperature (−196 to 500 °C) conditions. The outstanding combination of thermal and mechanical properties exhibited by these nanofibrous aerogel composites makes them highly promising for stable thermal protection in extreme environmental conditions. These novel materials promise great potential for application in various engineering industries where reliable thermal insulation is critical. [ABSTRACT FROM AUTHOR]

The fiber/aerogel material prepared by the traditional method of sol-gel has a serious powder shedding phenomenon, and has serious environmental pollution and health hazards. In this study, an environmentally friendly porous sound absorption material with a cage-like structure, which used flexible ultrafine glass/quartz hybrid fibers (HFs) as the carrier and SiO 2 aerogel as the pore filler, was produced using the wet manufacturing process. The addition of aerogel enhanced the internal reflection of sound waves, reduced the propagation speed, increased the acoustic energy loss and improved the sound absorption coefficient (SAC). The noise reduction coefficient (NRC) reaches 0.49 in the range of 250–6300 Hz. The obtained composite presented a low density (73.5 mg/cm3) and heat resistance up to 500 °C. [ABSTRACT FROM AUTHOR]