Functional p‐π Conjugated Organic Layer Empowers Stable Sodium Metal Batteries

Abstract Sodium metal batteries (SMBs) with the advantages of high energy density and low cost have attracted extensive attention as next‐generation rechargeable battery technology. However, SMBs suffer from severe Na dendrite and undesired solid electrolyte interface (SEI) layer, which inevitably destroy cycling durability and safety. Herein, a p‐π conjugated organic molecule (OHTAPQ) with redox‐active carbonyls and pyrazines is employed as a robust artificial SEI layer on Na anode (denoted as OHTAPQ@Na) to address these issues. The unique chelation of N and O with Na + ions in an OHTAPQ‐based layer facilitates good adsorption capacity and low Na + diffusion barries for uniform Na deposition behavior. As a result, the OHTAPQ@Na||OHTAPQ@Na symmetric cell shows a long‐term cycle lifespan (over 1500 h at 2 mA cm −2 ), and the OHTAPQ@Na||Na 3 V 2 (PO 4 ) 3 cells deliver a capacity retention of 82% after 1600 cycles. This research provides a handy way for anode protection with functional conjugated organics in SMBs.