Sb2Se3/CuSbSe2 Heterostructure@Carbon Enables High-Performance Sodium-Ion Battery Anodes

Abstract Sodium-ion batteries are emerging as highly promising candidates for large-scale energy storage systems due to the inexhaustible abundance and cost-effectiveness of sodium resources. Nevertheless, the practical implementation of conventional anode materials is severely hampered by sluggish reaction kinetics, drastic volume fluctuations, and inferior structural integrity during prolonged cycling. To address these intrinsic challenges, we rationally construct a Sb2Se3/CuSbSe2@C heterostructure as a high-performance anode via a facile one-step solvothermal method coupled with an annealing treatment. The experimental approach focuses on utilizing well-defined Sb2Se3/CuSbSe2 heterointerfaces to accelerate sodium ion diffusion and interfacial charge transfer, while simultaneously generating abundant active sites for robust sodium storage. As a result, the optimized Sb2Se3/CuSbSe2@C electrode delivers a remarkable reversible capacity of 338.8 mAh g-1 at an ultrahigh current density of 20.0 A g-1, and more impressively, maintains a robust capacity of 330.7 mAh g-1 over 2300 cycles at 5.0 A g-1. This work highlights the exceptional potential of heterostructured chalcogenides for advanced energy storage and offers a viable design pathway for next-generation batteries.