Interfacial Charge Transfer in Fluorinated Graphdiyne‐Confined SnO ₂ Nanotube Arrays for High‐Performance Sodium Storage

The charge transfer at heterointerface can significantly influence the sodium‐storage kinetics and durability of metal–oxide anodes for sodium ion battery. Here, this study reported the in situ fabrication of FGDY@SnO ₂ nanotube arrays electrode directly on a copper foil current collector. The FGDY/SnO ₂ heterointerface composed by fluorinated graphdiyne (FGDY) confined tin dioxide (SnO ₂ ) nanotube arrays feature incomplete interfacial charge transfer, with electrons transferred from FGDY to SnO ₂ , creating a locally modulated electronic environment that accelerates Na ⁺ transport and interfacial redox kinetics. Combined experimental and theoretical calculations have systematically revealed the synergistic advantages of the advanced FGDY@SnO ₂ electrode in terms of improving electrochemical reaction kinetics, stabling solid–electrolyte interphase and electrode structure. Thus, the FGDY@SnO ₂ anodes show high rate‐performance and stability. At a high current density of 5 A g ⁻¹ , FGDY@SnO ₂ can achieve a sodium storage capacity of 563.8 mAh g ⁻¹ . This work provides a material design paradigm for the fabrication of high‐rate and long‐cycle‐life Sn‐based anode toward advanced sodium‐ion batteries.