writer：Guorong Gao, F. Yang, F. Zhou, J. He, W. Lu, P. Xiao, H Yan, Caofeng Pan,* Tao Chen*, Zhonglin Wang*
keywords：hydrogels, ionic conductor, touch pad, self-healing, adhesiveness
source：期刊
specific source：Adv. Mater., 2020, 32, 2004290
Issue time：2020年

There is an increasing interest to develop next generation of touch pads that requires stretchability and biocompatibility to allow its integration with a human body, and even to mimic the self-healing behavior with fast functionality recovery upon damages. However, most touch pads have been developed based on stiff and brittle electrodes with the lack of important nature of self-healing. We developed polyzwitterion-clay nanocomposite hydrogels as the soft, stretchable and transparent ionic conductor with transmittance of 98.8% and fracture strain beyond 1500%, which could be used as a self-healing human-machine interactive touch pad with pressure sensitive adhesiveness on target substrates. A surface-capacitive touch system was adopted to sense a touched position. Finger positions were perceived during both point-by-point touch and continuous moving. Hydrogel touch pads were adhered to curved or flat insulators, with the high-resolution and self-healable input functions demonstrated by drawing, writing and play electrical games.