Controlling the Growth of Ni₃S₂ Anode with Tunable Sodium Storage

The influences of acids on the surface of nickel foam and its effect on the growth of nickel sulfide are studied. Treated by sulfuric acid, oxalic acid, and phosphoric acid, three Ni foams are fabricated with different surface states containing different surface roughness and different surface layers with nickel salts. By controlling the reaction conditions, three Ni 3 S 2 morphological structures with nanosheets, clustered nanosheets, and nanoparticles are designed on these preprocessed Ni foams. The applications of these Ni 3 S 2 /Ni electrodes for sodium ion batteries are examined in detail. The findings provide a new idea for the control of the solid–liquid reaction interface, which highly affect the morphologies of Ni 3 S 2 .