Construction of composite Zn metal anode based on phosphorus-doped carbon nanotubes for aqueous Zn-ion batteries

Aqueous Zn-ion batteries exhibit tremendous potential for large-scale energy storage applications due to the dual advantages of abundant Zn metal reserves and high theoretical capacity. However, practical applications are hindered by issues such as dendrite growth, electrode corrosion and hydrogen evolution. In this study, a composite anode composed of pre-deposited Zn on phosphorus-doped carbon nanotubes (P-CNT) is reported. On the one hand, the carbon nanotubes (CNTs) serve to reduce local current density during Zn deposition, enhancing corrosion resistance. On the other hand, the formation of a Zn₃P₂ interfacial layer facilitates more uniform Zn deposition, effectively suppresses dendrite growth, and mitigates the hydrogen evolution reaction (HER) to a certain extent. The composite anode exhibits a high coulombic efficiency of 98.9 % after 300 cycles. Furthermore, the full cell assembled with a LiMn₂O₄ (LMO) cathode demonstrates stable cycling performance over 900 cycles. This work presents a novel and robust design for a Zn metal anode in advanced aqueous Zn-ion batteries.