Initiating Hexagonal MoO for Superb-Stable and Fast NH Storage Based on Hydrogen Bond Chemistry.

Nonmetallic ammonium (NH ) ions are applied as charge carriers for aqueous batteries, where hexagonal MoO is initially investigated as an anode candidate for NH storage. From experimental and first-principle calculated results, the battery chemistry proceeds with reversible building-breaking behaviors of hydrogen bonds between NH and tunneled MoO electrode frameworks, where the ammoniation/deammoniation mechanism is dominated by nondiffusion-controlled pseudocapacitive behavior. Outstanding electrochemical performance of MoO for NH storage is delivered with 115 mAh g at 1 C and can retain 32 mAh g at 150 C. Furthermore, it remarkably exhibits ultralong and stable cyclic performance up to 100 000 cycle with 94% capacity retention and high power density of 4170 W kg at 150 C. When coupled with CuFe prussian blue analogous (PBA) cathode, the full ammonium battery can deliver decent energy density 21.3 Wh kg and the resultant flexible ammonium batteries at device level are also pioneeringly developed for potential realistic applications.