Deciphering H+/Zn2+ co-intercalation mechanism of MOF-derived 2D MnO/C cathode for long cycle life aqueous zinc-ion batteries

Poor conductivity, sluggish ion diffusion kinetics and short cycle life hinder the further development of manganese oxide in aqueous zinc-ion batteries (AZIBs). Exploring a cathode with high capacity and long cycle life is critical to the commercial development of AZIBs. Herein, a two-dimensional (2D) MnO/C composite derived from metal organic framework (MOF) was prepared. The 2D MnO/C cathode exhibits a remarkably cyclic stability with the capacity retention of 90.6% after 900 cycles at 0.5 A·g−1 and maintains a high capacity of 120.2 mAh·g−1 after 4500 cycles at 1.0 A·g−1. It is demonstrated that MnO is converted into Mn3O4 through electrochemical activation strategy and shows a Zn2+ and H+ co-intercalation mechanism. In general, this work provides a new path for the development of high-performance AZIBs cathode with controllable morphology.Graphical Abstract