2D Microporous Polymers/Reduced Graphene Oxide with Built‐In Lithiophilic Sites for Uniform Lithium Deposition in Lithium Metal Anode

Abstract Lithium (Li) metal is an attractive anode material for use in high‐energy lithium‐sulfur and lithium‐air batteries. However, its practical application is severely impeded by excessive dendrite growth, huge volume changes, and severe side reactions. Herein, a novel Li metal anode composed of lithiophilic two dimensional (2D) conjugated microporous polymer (Li‐CMP) and reduced graphene oxide (rGO) sandwiches (Li‐CMP@rGO) for Li metal batteries (LiMBs) is reported. In the Li‐CMP@rGO anode, the conductive rGO facilitates the charge transfer while the functionalized‐CMP provides Li nucleation sites within the micropores, thereby preventing dendrite growth. As a result, the Li‐CMP@rGO anode can be cycled smoothly at 6 mA cm⁻² of current density with a platting capacity of 2 mAh cm⁻² for 1000 h. A Coulombic efficiency of 98.4% is achieved over 350 cycles with a low overpotential of 28 mV. In a full cell with LiFePO₄ cathode, the Li‐CMP@rGO anode also exhibited good cycling stability compared to CMP@rGO and CMP/Super‐P. As expected, the simulation results reveal that Li‐CMP@rGO has a strong affinity for Li ions compared to CMP@rGO. The strategies adopted in this work can open new avenues for designing hybrid porous host materials for developing safe and stable Li metal anodes.