Driven by electricity: multilayered GO-Fe3O4@PDA-PAM flake assembled micro flower-like anode for high-performance lithium ion batteries

Up to now, how to endow the electrode, composed of the high theoretical capacity materials, with high capacity and high capacity retention for lithium ion batteries (LIBs) is still a great challenge. Herein, for the anodes of LIBs, mull-layered GO-Fe3O4@PDA-PAM (graphene oxide-Fe3O4@polydopamine-polyacrylamide) composites, in which Fe3O4 nanoparticles (NPs) are confined by the polydopamine (PDA) shell and reduced graphene oxide (rGO) sheets, are fabricated through a green and scalable strategy. The mull-layered structure with confined Fe3O4 NPs endows the anodes with efficient cushion effect and good electrical conductivity, leading to a good lithium ion storage capacity. More interestingly, GO-Fe3O4@PDA-PAM flakes are generated driven by the electricity and grabbed by PAM linker to form the flower-like morphology and well-maintained during the following electrochemical process. The flower-like anode holds up the aggregation of active materials and provides abundant lithium ion diffusion pathway. Therefore, based on the entire composite mass, the flowerstructured GO-Fe3O4@PDA-PAM anode displays a high reversible capacity, a good cycle reversibility (1204 mAh g(-1) after the 100th cycle at 0.3A g(-1)) and an admirable rate performance (702 mAh g(-1) at 1A g(-1)).