posted on 2023-08-29, 14:35authored byDingding Zong, Wenya Bai, Meng Geng, Xia Yin, Fei Wang, Jianyong Yu, Shichao Zhang, Bin Ding
Noise
pollution, as one of the three major pollutants
in the world,
has become a great burden on people’s health and the global
economy. Most present noise absorbers suffer large weight and inevitable
compromise between good low-frequency (usually <1000 Hz) and high-frequency
(typically >1000 Hz) noise reduction performance. This study presents
a scalable strategy to directly synthesize ultrafine fiber sponges
with ultrathin graphene-based vibrators by the synchronous occurrence
of humidity-assisted electrospinning and electrospraying. The unique
physical entanglements between reduced graphene oxide (rGO) nanosheets
and ultrafine fibers endow hierarchical vibration structured fiber
sponges (VSFSs) with excellent mechanical properties, which could
withstand large shear strain (60%) and tensile stress (6000 times
its weight) without damage and almost have no plastic deformation
after 1000 compressions. Attribute to the vibration effect of ultrathin
graphene-based vibrators and the viscous friction effect of porous
fiber networks, the VSFSs achieve both good low-frequency (absorption
coefficient of 0.98 in 680 Hz) and high-frequency sound absorption
(absorption coefficients above 0.8 in 2000–6300 Hz) simultaneously.
Furthermore, the noise reduction coefficient (NRC) of lightweight
VSFSs (thickness of 30 mm) reaches 0.63, which could reduce high decibel
noise by 24.4 dB, providing potential solutions for developing ideal
noise-absorbing materials.