Self-healable metal-organic gel membranes as anodes with high lithium storage

Abstract

Amorphous metal-organic gel (MOG) can be applied as anode for lithium ion batteries (LIBs) due to its advantages of the controllable structure and the adjustable pore size. In this work, M-MOGs (M=Ni, Zr, Fe, Al, Cr) membranes were fabricated by drop casting method and used as LIB anodes for the first time. They exhibited the excellent electrochemical performance, which were much better than metal-organic frameworks (MOFs) or MOGs without membrane formation of the same metal atom. There was no need to add carbon black, binder or organic solvent when fabricating the membrane electrode which can be attributed to the excellent electronic conductibility of membrane and the viscosity of MOGs. At the same time, the prepared MOGs have the self-healable property which can effectively restrain volume expansion during the lithium ion intercalation/extraction process. In five membrane electrodes, Ni-MOG membrane had a great specific capacity reaching to 1710.1 mA h g−1 at the current density of 100 mA g−1, and remained at 1245.5 mA h g−1 after 30 cycles with high rate performance. Furthermore, the coulombic efficiency was nearly 100% after 100 cycles at a high current density of 2 A g−1 or 5 A g−1. The conductivities of the five MOG membranes were between 10−8 and 10−7 S m−1, indicating that the membrane anodes had semiconductor property. It can be seen that amorphous MOG membrane is a promising anode material for LIBs. [Display omitted]