Constructing SnO2–MoSe2 heterojunction nanoflowers as high-rate and ultrastable anodes for sodium-ion half/full batteries

Abstract

Heterostructure engineering is one of the most promising modification strategies to enhance the thermodynamic stability and electrochemical kinetics of anode materials for sodium-ion batteries (SIBs). Herein, SnO₂/MoSe₂ heterojunction nanoflowers are successfully synthesized by a simple coprecipitation and hydrothermal strategy. The heterostructure material not only has many reactive active sites and fast ion migration channels, but also can slow down the agglomeration and improve the reversibility of the alloying reaction. The SnO₂/MoSe₂ anode exhibits outstanding performance for sodium storage, including a high discharge capacity of 572.9 mA h g⁻¹ after 200 cycles at 0.5 A g⁻¹ and an exceptional cycle lifespan of 364.3 mA h g⁻¹ at 10 A g⁻¹ over 5000 cycles. In addition, the full battery constructed with Na₃V₂(PO₄)₃ cathodes can show a capacity of 106.8 mA h g⁻¹ at 0.5 A g⁻¹ over 500 cycles and can also light up LED lights, showing potential commercial application value.