Advanced superionic conductor

Template:Short description An advanced superionic conductor (AdSIC) in materials science, is a fast-ion conductor that has a crystal structure close to optimal for fast-ion transport (FIT).

History

The term was introduced in a paper by A.L. Despotuli, A.V. Andreeva and B. Rambaby.

Characteristics

The rigid ion sublattice of Advanced SuperIonic Conductors (AdSICs) has structure channels where mobile ions of opposite sign migrate. Their ion-transport characteristics display ionic conductivity of ~0.3/Ω cm (RbAg₄I₅, 300 K) and activation energy of E_i~0.1 eV. This determines the temperature-dependent concentration of mobile ions ni~Ni x e^Ei/kBT capable to migrate in conduction channels at each moment (Ni~10²²/cm³, ni~2x10²⁰/cm³, 300 K).

The Rubidium silver iodide–family is a group of AdSIC compounds and solid solutions that are isostructural with the RbAg₄I₅ alpha modification. Examples of such compounds with mobile Ag⁺- and Cu⁺-cations include KAg₄I₅, NH₄Ag₄I₅, K_1−xCs_xAg₄I₅, Rb_1−xCs_xAg₄I₅, CsAg₄Br_1−xI_2+x, CsAg₄ClBr₂I₂, CsAg₄Cl₃I₂, RbCu₄Cl₃I₂ and KCu₄I_5.

RbAg₄I₅ AdSIC displays peculiar features of crystal structure and dynamics of mobile ions.

Recently, all solid state micrometre-sized supercapacitors based on AdSICs (nanoionic supercapacitors) had been recognized as critical electron component of future sub-voltage and deep-sub-voltage nanoelectronics and related technologies (22 nm technological node of CMOS and beyond). Researchers also developed an all-solid-state battery employing RbAg₄I₅ superionic conductor.