The First Proton-Conducting Metallic Ion-Radical Salts

摘要

Metallic materials that also conduct protons are being sought because of their potential as components in solid-state electrochemical devices,such as batteries and fuel cells.To date,the search has concentrated mainly on purely inorganic materials,and in particular continuous lattice oxides.In fact,there is a clear lack of candidates among electronically conducting organic molecular crystals,despite the existence of proton-conducting polymers,such as perfluorinated Nafion.Recently a 2,2'-[2,5-cyclohexadiene-l,4-diylidene]-bis(propanedinitrile) (TCNQ) charge transfer complex of benzimidazolyl-benzimidazole was shown to exhibit coupled protonic and electronic conductivity,and a TCNQ complex of l,4-diazabicylo[2.2.2]octane also exhibited proton transfer.