A Self-Adhesive Integrated Supercapacitors Integrated by Full Macromolecules for Implantable Applications

Flexible supercapacitors have become the top choice for wearable and implantable devices due to their stretchable mechanical adaptability and safety. However, in the current research situation, flexible supercapacitors still face many problems such as insufficient biocompatibility, lack of adhesiveness, or unstable interfaces. In this work, gelatin and polyacrylamide, which possess good biocompatibility, high water retention capacity, and good flexibility, are selected to construct a double-network hydrogel matrix. Tannic acid with abundant catechol groups is added to prepare the gel electrolyte membrane with good mechanical and adhesive properties. A conductive polymer PEDOT:PSS with good biocompatibility and conductivity is polymerized on the upper and lower surfaces of the hydrogel through simple in situ polymerization to form a symmetrically integrated supercapacitor. This device meets the basic requirements of high safety and good biocompatibility for implantable devices. At the same time, it has good adhesive properties, low interfacial impedance, and the characteristics of miniaturization and lightweightedness. This work provides a simple design concept and application potential for the development of wearable and implantable devices.