One-Step Synthesis of Na–Sn Alloy with Internal 3D Na<sub>15</sub>Sn<sub>4</sub> Support for Fast and Stable Na Metal Batteries
Olusola John Dahunsi, Bomin Li, Siyuan Gao, Ke Lu, Fan Xia, Tao Xu, Yingwen Cheng
Abstract
Na metal batteries are promising next-generation batteries but are constrained by the high reactivity of metallic Na. Here, we address this challenge by using a one-step-synthesized Na–Sn alloy anode with 1.6 at. % Sn. This anode has interconnected and sodiophilic Na15Sn4 backbones, which structurally support Na, enable faster Na+/Na redox kinetics, and guide dendrite-free Na plating with more stable solid-electrolyte interfaces. The composite Na@Na15Sn4 anode enabled very stable cycling of symmetric cells even at 5.0 mA cm–2 and improved the stability of full cells coupled with 3.0 mAh cm–2 Na3V2(PO4)3 cathodes to >90% capacity retention for 300 cycles.
Topics & Concepts
AnodeMaterials scienceAlloyElectrolyteCathodeMetalRedoxChemical engineeringReactivity (psychology)Plating (geology)KineticsComposite numberDendrite (mathematics)ElectrodeMetallurgyChemistryComposite materialPhysical chemistryGeophysicsPathologyMedicineMathematicsPhysicsGeologyQuantum mechanicsEngineeringAlternative medicineGeometryAdvanced Battery Materials and TechnologiesAdvancements in Battery MaterialsAdvanced Battery Technologies Research