Self-Healing, Anti-Fatigue, antimicrobial ionic conductive hydrogels based on Choline-Amino acid polyionic liquids for Multi-Functional sensors

Conductive hydrogels have recently attracted extensive attention due to their broad application prospects in flexible electronic devices and artificial intelligence. However, it is still a great challenge to develop integrated conductive hydrogels with excellent mechanical properties, efficient self-healing ability and high sensitivity. Moreover, most conductive hydrogels have no antimicrobial activity, which may lead to microbial infection during their applications. Herein, a series of versatile ionic conductive hydrogels based on choline-amino acid polyionic liquids(Cho-AA PILs) were designed by double network (DN) methodology. Owing to the reversible nature of dynamic coordination interaction, including metal coordination bonds, hydrogen bonds and electrostatic interactions, the resultant PIL hydrogels exhibited efficient self-healing ability, high energy dissipation capacity and outstanding fatigue resistance. The incorporation of Cho-AA PILs endowed hydrogels with not only high antimicrobial activity but also sensitive, rapid and stable strain sensing ability. The gauge factor(GF) and response time of PIL flexible sensors were 2.65 and 100 ms, respectively. During 1000 cycles, the electrical response signal of the strain sensor still remained stable. Significantly, PIL flexible sensors were able to monitor and distinguish large human body motions and subtle physiological activities and show sensitivity to pressure and handwriting. In addition, PIL hydrogels exhibited excellent biocompatibility. These results predicted that the prepared PIL hydrogels possess promising application prospects in the fields of artificial intelligence and biomedical engineering.