1. Metal-Organic Frameworks Triggered High-Efficiency Li storage in Fe-Based Polyhedral Nanorods for Lithium-ion Batteries.
- Author
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Shen, Lisha, Song, Huawei, and Wang, Chengxin
- Subjects
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NANORODS , *POLYHEDRAL functions , *LITHIUM-ion batteries , *ENERGY storage , *ELECTRODES - Abstract
Recently, metal organic framework (MOF) nanostructures have been frequently reported in the field of energy storage, specifically for Li-ion or Na-ion storage. By inter-separating the active sites of metal cluster and organic ligands, MOF nanostructures are exceptionally promising for realizing fast ion exchange and high-efficiency transportation and addressing the intricate issues that the energy-intensive Li-ion batteries have faced over many years. The related ion-storage mechanism remains to be explored. Is the traditional redox reaction mechanism operative for these nanostructure, as it is for transitional metal oxide? Herein, taking [Fe 3 O(BDC) 3 (H 2 O) 2 (NO 3 )]n (Fe-MIL-88B) as an example, an Fe-based metal organic polyhedral nanorods of MIL–88 B structure was designed as an anode for Li-ion storage. When tested at 60 mA g −1 , the nanoporous Fe-MIL–88 B polyhedral nanorods retained a reversible capacity of 744.5 mAh g −1 for more than 400 cycles. Ex situ characterizations of the post-cycled electrodes revealed that both the transition metal ions and the organic ligands contributed to the high reversible specific capacity. The polyhedral nanorods electrodes held the metal-organic skeleton together throughout the battery operation, although in a somewhat different manner than the pristine ones. This further substantiated that some MOF nanostructures are more appropriate than others for stable lithiation/delithiation processes. State-of-the-art CR2032 full cells showed that a high capacity of 86.8 mAh g −1 that was retained after 100 cycles (herein, the capacity for the full cell was calculated based on both the weight of the anode and the cathode, and the charge-discharge rate was 0.25C), when commercial LiFePO 4 powders were used as the cathode. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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