Fig. 1
From: Suppression of atom motion and metal deposition in mixed ionic electronic conductors
Atom migration and deposition in ion conductors. a Metallic Cu deposition on the surface of a Cu2S sample induced by a current. b–e Schematic of (b) the energy landscape for ions; c random ion motion without net flux; and d net ion flux under directional force or field. Due to a directional force or field and depending on the electrode constraints, MIECs may either reach a (e) steady state without net ion transport (and without metal deposition) or (f) continuous metal deposition (or other decomposition), if the local Cu concentration reaches a critical level determined by the stability range of the MIECs
