Interface manipulation of carrier transport and storage in ionic conductors

Ionically conducting materials may be purely ionic conducting and may also be mixed conducting with both ions and electrons.They are crucial materials for electrochemical devices for energy conversion and storage,chemical sensors,selective permeable membranes, and so on.In these devices, there exist two-dimensional or three-dimensional hetero-interfaces between the electrode and electrolyte,and between the different particles or grains.Thus,the ionic and electronic transport properties of these hetero-interfaces have a significant influence on device performance.However, it is far from clear how the interfaces affect these properties.In this context, two-dimensional heterostructures are advantageous for clarifying the mechanism of interface effects due to our ability to control the interfacial spacing and crystalline orientation.Such research is still in its infancy.This article will first introduce the background and developments of this field,then present some typical examples of the interfacial effects on carrier transport and storage which have been observed experimentally.The prospects for ion transport and storage by interface manipulation will also be briefly reviewed.