Zn-doped manganese tetroxide/graphene oxide cathode materials for high-performance aqueous zinc-ion battery

Due to its abundant zinc resources, high safety and low cost, aqueous zinc-ion batteries (AZIBs) are considered one of the most interesting lithium-ion battery replacement technologies. Herein, a novel Zn-doped cathode material is achieved via pre-intercalation of Zn 2+ into the prepared manganese tetroxide (Mn 3 O 4 )/graphene oxide (GO). The pre-intercalation of Zn 2+ effectively increases the lattice spacing of Mn 3 O 4 and reduces the barrier of insertion/extraction of Zn 2+ , thus improving the kinetic properties of the material. Meanwhile, the conductive carbon skeleton GO successfully combines with polyethyleneimine and Mn 3 O 4 , which can expand electron and ion conductivity and avoid chemical bulk change. This unique structure enables the Zn-doped cathode a reversible specific capacity with excellent performance (170 mAh g −1 at 200 mA g −1 ). Furthermore, the diffusion coefficient of the Zn-doped cathode is 10 −9 –10 −10 cm −2 s −1 . Therefore, this study introduces a viable approach for the practical implementation of advanced electrode materials in AZIBs applications. Graphical Abstract