Solid-state iontronics – double-layer electrolytes for ionic diodes

In double-layer polymer electrolytes, a sharp ion concentration gradient is spontaneously formed at the interface because of differences in ion coordination strength.

This boundary shows similarities with the p-n junction of semiconductor (double-layer) devices, but in an ionic rather than electronic form.

This ionic asymmetry, if sufficiently large, could potentially lead to a current-rectifying behavior, which is what this project intends to explore and utilize to create solid-state ionic diodes that show different ionic transport characteristics when biased in different directions.Based on an understanding of ion coordination in solid polymer electrolytes, this project aims tocreate polymer electrolytes with a wide range of ion coordination properties to combine into double-layer systemscharacterize the formed concentration gradients and correlate these to the ion coordination strengthinvestigate the evolution of the concentration gradients under an applied ionic current using in situ and operando methodscreate solid-state ionic diodes and demonstrate ionic current-rectifying behavior dependent on the coordination properties of the constituent materials