Multifunctional Electronic Skin Based on Perovskite Intermediate Gels

Electronic skin (e-skin) has attracted extensive attention owing to its potential application in biomedical sensors, intelligent robots, and bionic prostheses. To imitate better or even surmount the perceptive capabilities of human skin, multifunctional e-skin is an important trend in the field. A novel stable perovskite intermediate gel (PIGel) is obtained during the MA 2 SnI 6 perovskite crystallization process. This Sn-based PIGel exhibits good conductivity and outstanding wettability on different polymer substrates. Based on these properties, it is successfully applied to the field of e-skin. Flexible and stretchable multifunctional e-skin sensors are developed based on it. Stretching, finger bending, voice recognition, pulse monitoring, temperature, and electricity response are achieved in one e-skin device. In addition, the MA 2 SnI 6 perovskite single crystal is prepared by solvent engineering. The formation mechanism of the PIGel and MA 2 SnI 6 single crystal is studied in detail. This work broadens the selection range of sensing materials for e-skin and paves the way to achieve multifunctional sensors with the facile fabrication process.