Stable Zn Metal Anodes Enabled by Restricted Self-Diffusion Via Succinimide Surfactant

Despite its merits of high specific capacity and intrinsic safety for aqueous zinc-ion batteries (AZIBs), Zn metal as anode suffers from dendritic growth and severe corrosion during battery operation. Here, an electrolyte surfactant of succinimide (SI) that occupies the compact region of the electrical double layer (EDL) at the Zn/electrolyte interface, which protects the Zn surface from the parasitic corrosion in aqueous electrolytes is reported. More importantly, both theoretical calculation and electrochemical analysis demonstrate that the occupation of SI at the EDL can restrict the self-diffusion of Zn adatoms and tune interfacial reaction kinetics during Zn deposition, thereby promoting small and dense nuclei rather than large Zn dendrites. Accordingly, SI surfactants enable a high Coulombic efficiency of 99.95% and a long cumulative plated capacity over 6800 mAh cm(-2) at 20 mA cm(-2) for 10 mAh cm(-2). Moreover, the feasibility of SI is also demonstrated on a long-term cycling stability in Zn-VS2 batteries.

Automated summary

Introduced a surfactant of succinimide (SI) that occupies the compact region of the electrical double layer (EDL) at the Zn/electrolyte interface, protecting Zn surface from corrosion in aqueous electrolytes. SI surfactants restrict the self-diffusion of Zn adatoms and tune interfacial reaction kinetics, promoting small and dense nuclei instead of large Zn dendrites. SI enables high Coulombic efficiency and long-term cycling stability in Zn-VS2 batteries.