Zong Dingding, Bai Wenya, Geng Meng, Yin Xia, Yu Jianyong, Zhang Shichao, Ding Bin
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China.
Innovation Center for Textile Science and Technology, Donghua University, Shanghai 200051, China.
ACS Nano. 2022 Sep 27;16(9):13740-13749. doi: 10.1021/acsnano.2c06011. Epub 2022 Aug 11.
Aviation noise pollution has become a significant public health problem, especially with the endless improvement of flight speed and loading capacity. Existing aviation noise absorbers have fatal defects of large weight, weak high-temperature stability, and difficulty to achieve both good low-frequency (<1000 Hz) and high-frequency (up to 6000 Hz) noise absorption simultaneously. Herein, we report a robust strategy to create flexible ceramic nanofiber aerogels with cascaded resonant cavities by the air bubbles-assisted freeze-casting technology. The stable hinged resonance cavity structures coassembled by flexible ceramic nanofibers, soft montmorillonite nanosheets, and silica sol glue endow the aerogels with temperature-invariant compressibility (from -196 to 1100 °C) and bendability. Moreover, the comprehensive advantages of cascaded resonance cavities and interconnected fibrous networks enable flexible ceramic nanofiber aerogels to have temperature-invariant full-frequency noise absorption performance (noise reduction coefficient up to 0.66 in 63-6300 Hz). The synthesis of this flexible ceramic nanofiber aerogel provides a versatile platform for the design of high-efficiency noise-absorbing material for various fields.
航空噪声污染已成为一个重大的公共卫生问题，尤其是随着飞行速度和运载能力的不断提高。现有的航空噪声吸收器存在重大缺陷，如重量大、高温稳定性差，且难以同时实现良好的低频（<1000赫兹）和高频（高达6000赫兹）噪声吸收。在此，我们报告了一种通过气泡辅助冷冻铸造技术制备具有级联共振腔的柔性陶瓷纳米纤维气凝胶的稳健策略。由柔性陶瓷纳米纤维、软质蒙脱石纳米片和硅溶胶胶水共同组装而成的稳定铰接共振腔结构赋予了气凝胶温度不变的压缩性（从-196至1100°C）和可弯曲性。此外，级联共振腔和相互连接的纤维网络的综合优势使柔性陶瓷纳米纤维气凝胶具有温度不变的全频噪声吸收性能（在63-6300赫兹范围内降噪系数高达0.66）。这种柔性陶瓷纳米纤维气凝胶的合成提供了一个通用平台，用于设计适用于各种领域的高效吸声材料。
