Pang Kai, Ma Jingyu, Song Xian, Liu Xiaoting, Zhang Chengqi, Gao Yue, Li Kaiwen, Liu Yingjun, Peng Yuxin, Xu Zhen, Gao Chao
MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China.
Department of Sports Science, Zhejiang University, Hangzhou, 310058, P. R. China.
Small. 2024 Aug;20(34):e2400415. doi: 10.1002/smll.202400415. Epub 2024 May 2.
Highly flexible and superelastic aerogels at large deformation have become urgent mechanical demands in practical uses, but both properties are usually exclusive. Here a trans-scale porosity design is proposed in graphene nanofibrous aerogels (GNFAs) to break the trade-off between high flexibility and superelasticity. The resulting GNFAs can completely recover after 1000 fatigue cycles at 60% folding strain, and notably maintain excellent structural integrity after 10000 cycles at 90% compressive strain, outperforming most of the reported aerogels. The mechanical robustness is demonstrated to be derived from the trans-scale porous structure, which is composed of hyperbolic micropores and porous nanofibers to enable the large elastic deformation capability. It is further revealed that flexible and superelastic GNFAs exhibit high sensitivity and ultrastability as an electrical sensors to detect tension and flexion deformation. As proof, The GNFA sensor is implemented onto a human finger and achieves the intelligent recognition of sign language with high accuracy by multi-layer artificial neural network. This study proposes a highly flexible and elastic graphene aerogel for wearable human-machine interfaces in sensor technology.
在实际应用中，大变形下的高柔韧性和超弹性气凝胶已成为迫切的机械需求，但这两种特性通常是相互排斥的。在此，我们提出了一种在石墨烯纳米纤维气凝胶（GNFA）中的跨尺度孔隙率设计，以打破高柔韧性和超弹性之间的权衡。所得的GNFA在60%折叠应变下经过1000次疲劳循环后能够完全恢复，并且在90%压缩应变下经过10000次循环后仍能显著保持优异的结构完整性，性能优于大多数已报道的气凝胶。研究表明，机械鲁棒性源于跨尺度多孔结构，该结构由双曲线微孔和多孔纳米纤维组成，能够实现大弹性变形能力。进一步研究发现，柔性且超弹性的GNFA作为检测拉伸和弯曲变形的电传感器表现出高灵敏度和超稳定性。作为例证，GNFA传感器应用于人体手指，并通过多层人工神经网络实现了对手语的高精度智能识别。本研究为传感器技术中的可穿戴人机界面提出了一种高柔韧性和弹性的石墨烯气凝胶。
