Interface engineering enabled by sodium dodecyl sulfonate surfactant for stable Zn metal batteries.

According to the first principle, the SDS anions are preferentially adsorbed on the (0 0 2) surface of the Zn anode, forming a protective layer which prevents the adsorption of free water molecules and modifies the electrode/electrolyte interface. The SDS additive significantly inhibits the contact of water molecules with the interface, reduces the generation of by-products, and effectively prevents the growth of dendrites. Consequently, with the assistance of SDS additives, the Zn||Zn symmetrical battery sustains a long cycle life for 2000h. [Display omitted] Aqueous zinc-ion batteries are emerging as powerful candidates for large-scale energy storage, due to their inherent high safety and high theoretical capacity. However, the inevitable hydrogen evolution and side effects of the deposition process limit their lifespan, which requires rational engineering of the interface between anode and aqueous electrolyte. In this paper, an anionic surfactant as electrolyte additive, sodium dodecyl sulfonate (SDS), is introduced to deliver highly reversible zinc metal batteries. Unlike traditional surfactants, the solvation structure is not affected by SDS, which tends to adsorb on the (0 0 2) crystal plane of Zn with the purpose of effectively limiting the water molecules adsorption. Attributed to the natural hydrophobic part of SDS, a dynamic electrostatic shielding layer and a unique hydrophobic interface are constructed on the anode. Assisted by the above merits, the adverse surface corrosion, hydrogen evolution and dendrite growth are significantly inhibited without the sacrifice in the deposition kinetics of Zn ions. As a result, the Zn||Zn symmetric batteries demonstrate an increased cycle life of 2000 h (1 mA cm−2, 1 mA h cm−2) with the presence of SDS additive. Such strategy provides a new avenue for the developing advanced electrolytes to be applied in aqueous energy storage systems. [ABSTRACT FROM AUTHOR]