Preparation And Application Of MXene Nanocomposite For Flexible Sensors

In recent years,the rapid development of flexible and wearable sensors in the fields of electronic skin,artificial intelligence,and health monitoring has attracted tremendous attention from researchers.In this situation,we have designed an organohydrogel-based strain sensor with excellent anti-freezing,long-term moisture retention,and self-healing ability,and an organogel-based pressure sensor with excellent stability.The specific work is as follows:1.An anti-freezing,self-healing,and conductive MXene nanocomposite organohydrogel(MNOH)was developed by immersing MXene nanocomposite hydrogel(MNH)in ethylene glycol(EG)solution to replace a portion of the water molecules.The as-prepared MNOH exhibited an outstanding anti-freezing property(-40?),long-lasting moisture retention(8 days),and superior mechanical properties.Additionally,dynamic cross-linking between the hydroxyl group of polyvinyl alcohol(PVA)and tetrahydroxyl borate ions endowed a self-healing ability to the MNOH.In addition,MNOH can be prepared as a wearable strain sensor which still maintains a relatively wide strain range(up to 350%strain)and high sensitivity(Gauge Factor=44.85)at extremely low temperatures.It can be used to detect human motion,which shows tremendous potential applications for electronic skin,human-machine interfacing,and personalized medical monitoring.2.A flexible wearable pressure sensor based on MXene nanocomposite organogel(MNOG)was prepared by using hydrophobic polymer polybutyl acrylate(PBA)as the matrix and adding two-dimensional MXene sheet conductive filler,which showed excellent sensitive performance(S=0.27 kPa-1).In addition,benefited from the hydrophobic polymer matrix material,MNOG can effectively avoid the oxidative degradation of the internal MXene.It was demonstrated that the MNOG sensor still maintains a good electrical conductivity after 30 days,and at the same time,it can respond to the electrical signal of the finger bending activity.This work effectively improves the durability and stability of flexible wearable devices.