Humidity Sensing of Stretchable and Transparent Hydrogel Films for Wireless Respiration Monitoring  

作　　者：Yuning Liang Qiongling Ding Hao Wang Zixuan Wu Jianye Li Zhenyi Li Kai Tao Xuchun Gui Jin Wu 

机构地区：[1]State Key Laboratory of Optoelectronic Materials and Technologies and the Guangdong Province Key Laboratory of Display Material and Technology,School of Electronics and Information Technology,Sun Yat-Sen University,Guangzhou 510275,People’s Republic of China [2]Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace,Northwestern Polytechnical University,Xi’an 710072,People’s Republic of China

出　　处：《Nano-Micro Letters》2022年第11期218-236,共19页纳微快报（英文版）

基　　金：J.W.acknowledges financial supports from the National Natural Science Foundation of China(61801525);the Guangdong Basic and Applied Basic Research Foundation(2020A1515010693);the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(22lgqb17).

摘　　要：Respiratory monitoring plays a pivotal role in health assessment and provides an important application prospect for flexible humidity sensors.However,traditional humidity sensors suffer from a trade-off between deformability,sensitivity,and transparency,and thus the development of high-performance,stretchable,and low-cost humidity sensors is urgently needed as wearable electronics.Here,ultrasensitive,highly deformable,and transparent humidity sensors are fabricated based on cost-effective polyacrylamide-based double network hydrogels.Concomitantly,a general method for preparing hydrogel films with controllable thickness is proposed to boost the sensitivity of hydrogel-based sensors due to the extensively increased specific surface area,which can be applied to different polymer networks and facilitate the development of flexible integrated electronics.In addition,sustainable tapioca rich in hydrophilic polar groups is introduced for the first time as a second cross-linked network,exhibiting excellent water adsorption capacity.Through the synergistic optimization of structure and composition,the obtained hydrogel film exhibits an ultrahigh sensitivity of 13,462.1%/%RH,which is unprecedented.Moreover,the hydrogel film-based sensor exhibits excellent repeatability and the ability to work normally under stretching with even enhanced sensitivity.As a proof of concept,we integrate the stretchable sensor with a specially designed wireless circuit and mask to fabricate a wireless respiratory interruption detection system with Bluetooth transmission,enabling real-time monitoring of human health status.This work provides a general strategy to construct high-performance,stretchable,and miniaturized hydrogel-based sensors as next-generation wearable devices for real-time monitoring of various physiological signals.

关 键 词：Stretchable and transparent humidity sensors Hydrogel film Wireless and wearable sensor Respiration monitoring Ultrasensitive 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] TQ427.26[自动化与计算机技术—控制科学与工程] TB383.2[化学工程]