High-power iontronics enabled by nanoconfined ion dynamics

Tailoring ion dynamics within nanoconfined spaces presents a new approach for developing advanced iontronic devices. Using various nano-hierarchical materials with nanoconfined spaces can regulate anomalous ionic behaviors, but research on coupling interfacial reactions and ionic dynamics in nanoconfined spaces remains unclear, which limits their applications in energy harvesting. Here, we develop an ultrathin (∼10.5 μm), solid-state, and high-power iontronic power source with an areal energy density of ∼1.4 kWh m−2 and power density of ∼16.07 kW m−2. This is achieved by coupling fine-tuned interfacial Ag/Ag+ redox reactions with efficient cation transport in graphene oxide (GO) nanoconfined channels. The iontronics can also be printed over a large fractal area and be self-charged by a triboelectric nanogenerator, which is crucial for futuristic wearable electronics and neuronal-computer interfaces. This work provides a paradigm of coupling various redox reactions to expand the iontronic systems to wider prospective applications.