“…in 2012, [3] achievements have been made on NH 4 + storage for aqueous energy storage (Figure 1). Ti 3 C 2 MXene, [4] Prussian blue analogues (e.g., sodium iron hexacyanoferrate, [5] copper hexacyanoferrate, [6] berlin green, [7] ammonium Prussian white [2] ), organic solids (e.g., 3,4,9,10‐perylenetetracarboxylic diimide, [2] polyaniline [8] ), and metal oxides (e.g., titanic acid, [9] V 2 O 5 , [10] MoO 3 , [11] NH 4 V 4 O 10 [8] ) were studied to enrich the NH 4 + ‐storage chemistry. For example, Ji et al.…”