| Lithium metal,as the best anode material for the next-generation lithium metal batteries due to its high theoretical specific capacity(3860 mA h g-1).However,Li dendrites generated during Li plating/striping cycles severely handicap its commercial application directly as an anode because of poor cycling stability and vital safety risks.Herein,a lithium metal host material based on graphene and carbon nanotubes(CNT)is prepared.which features vertically aligned channels with attached lithiumphilic ZnO particles(designated as ZnO@G-CNT-C)for regulating Li plating and stripping.The Zn0@G-CNT-C is prepared from an aqueous suspension of CNTs and graphene oxide using an ice-template method.During the preparation process,the ice-template method is used to effectively control the formation of the pore structure of ZnO@G-CNT-C.Thus,the material possesses excellent mechanical properties and tunable functionabilities.The composition and structural features of ZnO@G-CNT-C electrode led to Li deposition on the inner walls of the channels without the formation of Li dendrites.Therefore,the ZnO@G-CNT-C electrode exhibits lower polarization associated to Li plating,faster Li-ion diffusion,and more stable coulombic efficiency during Li plating/stripping cycle,when compared with the dense film made from the same material or Cu foil as the lithium metal hosts.In order to verify the application of ZnO@G-CNT-C in the full batteries,full cells prepared from ZnO@G-CNT-C as Li host and LiFePO4 as cathode exhibit outstanding performances in terms of specific capacity(155.9 mA h g-1 at 0.5 C),rate performance(91.9 mA h g-1 at 4 C),cycling stability(109.1 mA h g-1 at 0.5 C after 800 cycles).This paper proposes a method for preparing lithium metal hosts with vertically aligned channels.The initial materials are abundant and the control method of the channel structure is simple.It has the prospect of entending to the preparation of electrode structures of other types of energy storage devives. |
