posted on 2021-12-27, 17:47authored byShuai Hao, Tianci Li, Xuemeng Yang, Hongzan Song
Developing multifunctional stretchable
ionic skin (I-Skin) to mimic
the sensations of the human skin is of great interest and shows promising
potential in wearable sensors and human–machine interfaces
(HMIs). However, common ionogels prepared with small-molecule cross-linkers
and single networks can hardly satisfy the requirements of adjustable
mechanical properties, strong adhesion, fast self-healability, and
good stability in extreme environments. Herein, an ultrastretchable
(>10,000%), ultrastrong adhesive (>6.8 MPa), ultrafast self-healable
(10 s), high thermally stable (−60 to 250 °C), and three-dimensional
(3D)-printable photoluminescent ionogel with shape memory properties
has been designed. The ionogel consists of hyperbranched polymer covalent-cross-linked
poly(zwitterionic ionic liquid)-co-poly(acrylic acid) and multiple
dynamic bonding cross-linked networks. The excellent performance of
the ionogel-based high-stretchable strain sensor and the triboelectric
nanogenerator (TENG)-based self-powered touch sensor is further demonstrated
over a wide temperature range (−40 to 150 °C). More importantly,
ionogel-based I-Skin can work as an HMI for human gesture recognition
and real-time wireless control of robots under extreme vacuum conditions
and can also self-heal immediately along with function recovery after
mechanical damage.