In-situ self-assembled hollow urchins F-Co-MOF on rGO as advanced anodes for lithium-ion and sodium-ion batteries

To obtain MOFs materials with good electrochemical performance in both lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), a kind of hollow urchins Co-MOF with doping fluorine (F) was in-situ assembled on reduced graphene oxide (rGO) using a simple solvothermal reaction. According to XRD, XPS and EDS mapping analysis, the molecular structure should be Co-2[F-x(OH)(1-x)](2)(C8O4H4) (denoted as F-Co-MOF). When the composite material is used as active material to assemble LIBs, it not only presents the outstand-ing reversible capacity (1202.0 mA h g(-1) at 0.1 Ag-1), but also gives the excellent rate performance and cycle performance (771.5 mA h g(-1) at 2 A g(-1) after 550 repeated cycles). The remarkable lithium storage capacity of F-Co-MOF/rGO is also reflected in the full cell, where it can still maintain a high capacity of 165.2 mA h g(-1) after 300 cycles at 0.2 A g(-1). It benefits from the synergistic effect of F-Co-MOF and high conductive rGO networks, so that the reversibility of lithium and sodium storage can be improved. This kind of F doped solvothermal synthesis of MOFs is of great significance for the exploration of high performance materials. (C) 2020 Elsevier Inc. All rights reserved.

Automated summary

The F-doped hollow urchin Co-MOF/rGO composite shows excellent reversibility, rate performance, and cyclic stability in LIBs, with high capacity retention in full cell configurations.