Regulation of the Electrochemical Plating/Stripping Process for Zn: Multifunctional Effects of N, S-Codoped Carbon Dots

The aqueous zinc-ion battery is considered as one of the best alternatives to lithium-ion batteries due to its low cost and high safety. However, the inevitable dendrite growth, byproduct formation, and the side reactions have inhibited the application of aqueous zinc-ion batteries. In this work, the electronegative nitrogen and sulfur-codoped carbon dots (NSCDs) are proposed as an electrolyte additive to regulate the uniform distribution of zinc ions and inhibit the growth of dendrites. It was found that only a small amount of NSCD additive (0.2 mg mL–1) exerted a significant influence in electrochemical performance; the symmetrical cell can operate stably for 2000 h with a low voltage hysteresis of 33 mV at the current density of 1 mA cm–2, and a high Coulombic efficiency (CE) of 99.5% can be obtained after 250 cycles.