Controllable morphological transformations of nickel metal–organic frameworks for nickel–zinc batteries
Guangxun Zhang, Hui Yang, Wanchang Feng, Qiujing Wang, Han‐Yi Chen, Mohsen Shakouri, S.Y. Chen, Huan Pang
Abstract
Abstract Constructing hierarchical nanostructures with highly exposed surfaces is a promising strategy for developing advanced cathode materials in aqueous batteries. Herein, we employed a competitive coordination strategy to optimize the characteristics of nickel metal–organic framework (Ni‐MOF). Specifically, the acetate ions were employed as precise regulators, exerting a distinct influence on the morphology of the Ni‐MOF and leading to a structural transition from a block structure to a two‐dimensional (2D) layered structure. The optimized Ni‐MOF exhibits a unique superstructure composed of hierarchical 2D layers assembled into flower‐like architectures. This distinctive superstructure increases the electrochemically active surface area of Ni‐MOF (N‐2) and provides abundant pathways for electron/ion transfer, thereby facilitating efficient electrochemical reactions. Remarkably, the assembled aqueous alkaline N‐2//Zn battery demonstrated enhanced specific capacity (0.446 mAh·cm −2 at 1 mA·cm −2 ) and excellent maximum energy/power density (0.789 mWh·cm −2 /17.262 mW·cm −2 ). This work not only offers valuable insights into regulating MOF morphology, but also makes a contribution toward enhancing the application potential of MOFs in aqueous batteries.