CoFe2O4 derived-from bi-metal organic frameworks wrapped with graphene nanosheets as advanced anode for high-performance lithium ion batteries

Abstract CoFe 2 O 4 /graphene nanosheets (GNS) nanocomposites derived from bi-metal organic frameworks and graphene oxides were firstly synthesized via a facile one-pot chemical precipitation with subsequent thermal decomposition method. The as-prepared CoFe 2 O 4 /GNS were characterized by XRD, Raman, SEM, TEM and BET adsorption-desorption. As an anode for lithium ion batteries, the CoFe 2 O 4 /GNS nanocomposites exhibited an obvious enhancement electrochemical property in terms of a higher discharge capacity of 1061.7 mAh g −1 after 100 cycles at 100 mA g −1 with 75.1% capacity retention and the excellent reversible capacity of 956.2 mAh g −1 when the charge-discharge rate returned from 2 A g −1 to 0.1 A g −1 after 60 cycles. This enhancement could be attributed to the synergistic effects between Co and Fe oxides, and the graphene nanosheets which could not only accommodate the volume variations of CoFe 2 O 4 nanoparticles during cycling, but also improve the contact area between electrolyte and electrodes.