Design Nitrogen (N) and Sulfur (S) Co‐Doped 3D Graphene Network Architectures for High‐Performance Sodium Storage

To develop high‐performance sodium‐ion batteries (NIBs), electrodes should possess well‐defined pathways for efficient electronic/ionic transport. In this work, high‐performance NIBs are demonstrated by designing a 3D interconnected porous structure that consists of N, S co‐doped 3D porous graphene frameworks (3DPGFs‐NS). The most typical electrode materials (i.e., Na₃V₂(PO₄)₃ (NVP), MoS₂, and TiO₂) are anchored onto the 3DPGFs‐NS matrix (denoted as NVP@C@3DPGFs‐NS; MoS₂@C@3DPGFs‐NS and TiO₂@C@3DPGFs‐NS) to demonstrate its general process to boost the energy density of NIBs. The N, S co‐doped porous graphene structure with a large surface area offers fast ionic transport within the electrode and facilitates efficient electron transport, and thus endows the 3DPGFs‐NS‐based composite electrodes with excellent sodium storage performance. The resulting NVP@C@3DPGFs‐NS displays excellent electrochemical performance as both cathode and anode for NIBs. The MoS₂@C@3DPGFs‐NS and TiO₂@C@3DPGFs‐NS deliver capacities of 317 mAhg^?1 at 5 Ag^?1 after 1000 cycles and 185 mAhg^?1 at 1 Ag^?1 after 2000 cycles, respectively. The excellent long cycle life is attributed to the 3D porous structure that could greatly release mechanical stress from repeated Na⁺ extraction/insertion. The novel structure 3D PGFs‐NS provides a general approach to modify electrodes of NIBs and holds great potential applications in other energy storage fields.