Oxygen and nitrogen co-doped porous carbon granules enabling dendrite-free lithium metal anode

Lithium (Li) metal anode is one of the most promising candidates for next-generation storage system due to its high theorectical capacity. However, the uncontrollable growth of Li dendrites still incurs serious safety issues and poor electrochemical performances, hindering the practical application of Li metal anode. Herein, oxygen and nitrogen co-doped porous carbon granules (ONPCGs) with high specific surface area (2396 m² g⁻¹) made from polyacrylonitrile powder were used as the host material for Li plating. The lithiophilic oxygen and nitrogen-containing functional groups could guide a uniform Li nucleation deposition, and the high specific surface area of ONPCGs could lower the regional electrical field effectively, boosting stable and homogeneous Li plating. Therefore, the ONPCG modified electrode delivered a stable Li plating/stripping with high Coulombic efficiencies>99% for over 350 cycles at a current of 2 mA cm⁻² and Li capacity of 2 mAh cm⁻², with a Coulombic efficiency of 96.4% after 130 cycles at a current of 20 mA cm⁻². Even at exceptional high current density of 30 mA cm⁻², it could stably being cycled for over 110 cycles. Furthermore, the full cells, using sulfurized carbon as cathode and ONPCGs@Li as anode, could also demonstrate excellent cycle and rate performances.