Designed Tetranuclear Iron‐oxo Clusters with Redox Activity for High‐Performance Lithium Storage
Jiangjiang Lv, Bo Li, Qianqian Liu, Zhixin Gao, Zhongling Lang, Song Liang, Yingqi Li, Hong‐Ying Zang
Abstract
Abstract Polyoxometalates (POMs) are considered as promising catalysts with unique redox activity at the molecular level for energy storage. However, eco‐friendly iron‐oxo clusters with special metal coordination structures have rarely been reported for Li‐ion storage. Herein, three novel redox‐active tetranuclear iron‐oxo clusters have been synthesized using the solvothermal method with different ratios of Fe 3+ and SO 4 2− . Further, they can serve as anode materials for Li‐ion batteries. Among them, cluster H 6 [Fe 4 O 2 (H 2 O) 2 (SO 4 ) 7 ]⋅H 2 O, the stable structure extended by SO 4 2− with a unique 1D pore, displays a specific discharge capacity of 1784 mAh g −1 at 0.2 C and good cycle performance (at 0.2 C and 4 C). This is the first instance of inorganic iron‐oxo clusters being used for Li‐ion storage. Our findings present a new molecular model system with a well‐defined structure and offer new design concepts for the practical application of studying the multi‐electron redox activity of iron‐oxo clusters.