Implantable and biodegradable micro-supercapacitor based on a superassembled three-dimensional network Zn@ppy hybrid electrode

Transient supercapacitors (TSCs), a new type of advanced supercapacitor (SC) that can completely dissolve with environmentally and biologically benign byproducts in vivo after performing their specified function, have broad application prospects in the fields of green electronics, implantable devices, personalized medicine, military security, and other fields. However, research on TSCs is still in its infancy, and there are still many challenges to be solved, such as the complex preparation process and low energy density. Herein, we report a facile superassembly manufacturing method for an implantable and fully biodegradable three-dimensional network Zn@PPy hybrid electrode by screen printing and electrochemical deposition. The produced superassembled interdigital pseudocapacitor exhibits superior electrochemical performances due to the high capacitances and excellent rate performances of the pattern Zn@PPy electrode and NaCl/agarose electrolyte. An optimized biodegradable SC exhibits a maximum energy density of 0.394 mW h cm⁻² and can be fully degraded in vivo in 30 days without any adverse effects in the host organism. This work provides a new platform for transient electronic technology for diverse implantable electronic applications.