A high-capacity polyaniline-intercalated layered vanadium oxide for aqueous ammonium-ion batteries.

A 1.55 nm-interlayer spacing-expanded polyaniline-intercalated vanadium oxide, as a new electrode material for NH 4 + -ion batteries, exhibits the highest ever reported capacity of ∼307 mA h g -1 at a current density of 0.5 A g -1 . In situ FT-IR and XPS studies confirm the reversible NH 4 + storage is accompanied by H bond formation/breaking within the functional group of -VO···H.