Sn-based metal–organic framework derived composites as anode materials for sodium-ion batteries with high cycling stability

Alloy anode materials are susceptible to significant volume changes during charging and discharging, which lead to poor cycling performance. However, materials derived from metal–organic frameworks (MOFs) can effectively mitigate this problem. The carbon skeleton not only supports the structure and buffers volume changes but also enhances electronic conductivity, thereby improving the sodium storage performance of the anode. In this study, a Sn-based metal–organic framework (Sn-MOF) was synthesized using a co-precipitation method. Anode materials derived from Sn-MOF with a porous structure were obtained by varying the heat treatment temperature. An increased number of pores in the material not only alleviates volume changes but also enhances the contact area between the electrode material and the electrolyte, thus providing more active sites for sodium storage. Among the various materials studied, the Sn-MOF-800 electrode exhibits excellent electrochemical performance. When utilized as an anode material in sodium-ion half-cells, it maintains a specific capacity of 451.43 mAh g −1 after 100 cycles at a current density of 100 mA g −1 , and a specific capacity of 477.7 mAh g −1 after 250 cycles at a current density of 500 mA g −1 , demonstrating remarkable cycling stability. This paper serves as a valuable reference for the design of simple and cost-effective anode materials for sodium-ion batteries.