Metal-Hydroxide Organic Frameworks for Aqueous Nickel-Zinc Batteries
Shixian Wang, Yichun Su, Zhaocheng Jiang, Zhenyang Meng, Tianyi Wang, Meifang Yang, Weijie Zhao, Han‐Yi Chen, Mohsen Shakouri, Huan Pang
Abstract
Hydroxides exhibit a high theoretical capacity for energy storage by ion release and are often intercalated with anions to enhance the ion migration kinetics. In this study, a series of metal-hydroxide organic frameworks (MHOFs) are synthesized by intercalating aromatic organic linkers into hydroxides using I-M/Ni(OH) 2 (where M = Co 2+, Cu 2+, Mg 2+, Fe 2+ ). The coordination environment and layer spacing (1.09 nm) of I-M/Ni(OH) 2 are explored by X-ray absorption fine structure and cryo-electron microscopy. The intercalation nanostructure improves the conductivity of the hydroxides and facilitates Zn 2+ migration by increasing the interlayer spacing, while enhancing the rate capability and cycling stability. Consequently, the I-Co/Ni(OH) 2 material exhibites a satisfactory specific capacity of 0.35 mAh cm –2 at 3 mA cm –2 and a high peak power density of 6.78 mW cm –2 . This study offers a novel perspective on the design of intercalated hydroxide and provides new insights into high-performance nickel-zinc batteres.