Ultralight and Strain-sensitive Bacterial Cellulose derived Carbon fiber-reinforced Graphene Aerogel for Broadband Sound Absorption

The growing severity of urban noise pollution poses a threat to the physical and mental health of residents, prompting the need for the development of effective sound-absorbing materials. Herein, we present a versatile method to fabricate ultralight and flexible graphene-based aerogels by introducing one-dimensional carbon fibers as reinforcements. These carbon nanofiber-reinforced graphene aerogels (CNF/GAs) were obtained by the carbonization of freeze-casted bacterial cellulose/graphene oxide (BC/GO). Our CNF/GAs possess a low apparent density (∼3.05 mg·cm-3) and exhibit broad-band sound absorption performance with a superior noise reduction coefficient (NRC) as high as 0.65 at a thickness of 30 mm. Meanwhile, their excellent elasticity endows the CNF/GAs with strain-sensing capability, enhancing their capacity for detecting deformations when utilized as sound absorbers in engineering applications. Additionally, the highly porous structure makes the CNF/GAs excellent thermal insulators, with a thermal conductivity as low as 0.011 W·m-1·K-1, further expanding their environmental reliability. Therefore, our approach develops CNF/GAs with excellent broad-band sound absorption performance and mechanical-environmental reliability, showing significant practical potential.