Printable high-performance iontronic power source based on osmotic effects

Iontronic power sources have attracted widespread attention in the field of energy harvesting and storage. However, conventional devices only generate an output voltage of ~ 1.0 V. Herein, we have developed units with an ultra-high voltage of ~2.0 V per unit based on osmotic effects and fine-tuning interfacial redox reactions. These systems are designed to harness the efficient ion dynamics of K⁺ within graphene oxide nanofluidic channels and tailor Faradaic processes at the interfaces. Printable, scalable, and optimized through fractal design, these miniaturized units are capable of directly powering commercial electronics, presenting a transformative paradigm for salinity gradient-based power generation. This approach offers a safe, ultra-thin, and portable solution for next-generation energy systems.