Oxygen-rich carbon nanotube networks for enhanced lithium metal anode

Developing safe and efficient lithium (Li)-metal anode is promising for the next-generation rechargeable batteries, such as Li–S and Li–O2 batteries. The design of lithium plating host with unique nanostructure and lithiophilic surface has been proven to be one of the most efficient strategies to control Li plating/stripping process and inhibit lithium dendrite growth. Here we first report the fabrication of well-defined oxygen-rich carbon nanotube (O-CNT) network via a facile and scalable ultrafast "barbecue" approach. Remarkably, the as-obtained three-dimensional (3D) O-CNT network electrode can serve as a promising Li-metal host with a low Li deposition overpotential and a flat voltage profile at various current densities, as well as long-term durability. The DFT calculation and experimental results further prove that the ketonic (C=O) group on CNT surface acts as efficient lithiophilic site to guide Li-metal nucleation and growth. In addition, the 3D porous network structure of O-CNT network with high conductivity facilitates electron and Li ions transport. Thus, this work provides a new strategy to construct high-performed Li-metal anodes toward high-performance Li-based batteries.