High electrochemical performance of Fe ₂ O ₃ @OMC for lithium-ions batteries

Abstract

Abstract Fe 2 O 3 @OMC (ordered mesoporous carbon) is synthesized using Fe-MOFs (metal-organic frameworks). The Fe 2 O 3 @OMC pore size is mostly concentrated at approximately 2–4 nm. Compared to traditional OMC or carbonized Fe-MOFs, Fe 2 O 3 @OMC demonstrates a higher capacity (the capacity remains at 1176.6 mAh g −1 after 500 cycles under a current density of 0.1 A g −1 ) and a longer cycle life. The first cycle capacity of Fe 2 O 3 @OMC is ultrahigh at 2448.6 mAh g −1 , and the reversible capacity is 1294.1 mAh g −1 . Fe 2 O 3 @OMC maintains a good performance under current densities of 0.1 A g −1 , 0.2 A g −1 , 0.5 A g −1 , 1 A g −1 , 2 A g −1 , and 5 A g −1 , with electric capacities of 1100.8 mAh g −1 , 1017.6 mAh g −1 , 849.3 mAh g −1 , 690.7 mAh g −1 , 506.7 mAh g −1 , and 272.1 mAh g −1 , respectively. Thus, the material has good rate performance. Combining iron oxide and MOFs is helpful to improve the capacity performance.