Engineered Crystalline Heterostructure Interphase Enabling Dendrite-Free Sodium Metal Anodes with Long-Term Stability
Fenqiang Qi1, Xueming Su1, Ziling Huang1, Jun Yang4, Hongwei Gu1(顾宏伟)*, Jian-Ping Lang1,2,3(郎建平)*
1College of Chemistry Chemical Engineering and Materials Science, Soochow University, Suzhou, Jiangsu 215123, P. R. China
2State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences, Shanghai 200032, P. R. China
3State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering Nanjing University Nanjing 210023, P. R. China
4School of Materials Science and Engineering Jiangsu University of Science and Technology, Jiangsu 212003, P. R. China
Adv. Mater. 2026, 38, e12214
Abstract: The advancement of sodium-ion batteries (SIBs) critically depends on the development of stable sodium metal anodes (SMAs). However, practical implementation remains hindered by uncontrollable dendritic growth and uneven Na stripping/plating behavior associated with pristine sodium metal. In this study, the design of a robust triphasic heterojunction artificial interphase is reported, formed via a spontaneous in situ reaction between Ag3PO4 and metallic sodium. The resulting Ag2Na/Ag/Na3PO4 interphase synergistically combines metallic, alloy, and ionic phases to simultaneously regulate ion transport and suppress dendrite formation. Specifically, the Ag2Na alloy and metallic Ag components ensure strong interfacial adhesion and enhanced electronic conductivity, while the Na3PO4 phase promotes homogeneous Na⁺ ion flux and accelerates surface diffusion via its desolvation capability. Benefiting from this engineered interface, the Na/Ag3PO4 anode exhibits a remarkably low nucleation overpotential of 27 mV and delivers stable cycling performance exceeding 1600 h at 0.5 mA cm−2 (1 mAh cm−2) in symmetric cells. Moreover, a full sodium metal pouch cell incorporating the Na/Ag3PO4 anode achieves a high energy density of 425.5 Wh kg−1, underscoring the practical viability of this interfacial design for next-generation high-energy SIBs.
Article information: //doi.org/10.1002/adma.202512214
