Mechanically robust and multifunctional polyimide/MXene composite aerogel for smart fire protection

作者：Jiang, Changcheng; Chen, Jiayun; Lai, Xuejun^*; Li, Hongqiang; Zeng, Xingrong; Zhao, Yinan; Zeng, Qingtao; Gao, Jiefeng; Wu, Zhengzhong; Qiu, Yunkun

来源：Chemical Engineering Journal, 2022, 434: 134630.

DOI：10.1016/j.cej.2022.134630

• Polyimide aerogel
• MXene
• Fire-warning
• Temperature sensing
• Piezoresistive sensing

Multifunctional smart fire-protection aerogels are urgently needed to meet the requirement of the Internet of Everything era. Herein, we fabricated a mechanically robust and high fire-safe polyimide/MXene composite aerogel (denoted as PI@MXene) with sensitive temperature-sensing and fire-warning capability. Thanks to the unique thermoelectric effect and high electrical conductivity of the 2D transition metal carbide (MXene) nanosheet, PI@MXene exhibited a linear relationship between the thermoelectric voltage and the temperature difference, showing sensitive temperature-sensing capability. When being burned, it could repeatedly trigger the fire-warning system in less than 5 s. More importantly, owing to the lamellar barrier and skeleton supporting effect of the MXene nanosheets, PI@MXene exhibited excellent flame retardancy, which self-extinguished within 1 s after exposing to a flame for 60 s and whose peak heat release rate was significantly decreased by 78% compared with PI aerogel. Besides, PI@MXene showed impressive thermal insulation, outstanding thermostability and durable piezoresistive sensing. This work provides a novel strategy to fabricate next-generation multifunctional fireproof aerogel, showing promising applications in intelligent robots, aerospace, and railway transportation.