Nitrogen doped carbon nanotube interface modified coating provides stable zinc anode for aqueous zinc ions

Aqueous zinc-ion batteries (ZIBs) have attracted considerable scholarly interest due to their notable advantages, including high safety, cost-effectiveness, and environmental sustainability. Nonetheless, the cycling process is often accompanied by the formation of zinc dendrites on the anode surface and the initiation of side reactions, which can result in battery short circuits. In this study, a surface coating for the zinc anode was developed through the doping of carbon nanotubes (CNTs) with ammonium chloride (NH 4 Cl, containing 26.2 % nitrogen). The side reactions in ZIBs and dendrite growth were effectively addressed during cycling. In tests at a current density of 1 mA cm⁻² and a capacity density of 1 mAh cm⁻², the N-CNT@Zn anode exhibited a cycle life exceeding 1800 h and the overpotential of only 10 mV. Additionally, under the same current density conditions, the N-CNT@Zn//Cu symmetric battery maintained a Coulombic efficiency (CE) of 100.74 % after 200 cycles. It is also important to note that the N-CNT@Zn anode-equipped zinc-manganese battery demonstrated a specific capacity of 129 mAh g⁻¹ after 2000 cycles at a current density of 10 A g⁻¹ . Furthermore, high-temperature testing indicated that the N-CNT@Zn anode-equipped zinc-manganese battery can be utilized under high-temperature conditions of 40°C. • We synthesized N-CNT materials by doping. • N-CNT@Zn//N-CNT@Zn exhibits high cycling performance and stability. • N-CNT@MnO 2 demonstrates high capacity, long cycling life, and excellent rate performance.