Stabilization of Sb nanoparticles using metal–organic frameworks to obtain stable performance of anode material for sodium-ion batteries

Excerpt

Sodium-ion batteries (SIBs) have received much attention as a potential energy storage system to replace lithium-ion batteries (LIBs) due to the abundant sodium resources and low cost [1, 2]. Recently, conversion materials [3], insertion-type materials [4], and alloying-type compounds [5] have been used as anode materials for SIBs. Among them, Sb-based material, an alloying-type anode material, has been widely investigated due to the following reasons: (1) good safety due to the high operating voltage (0.5–0.8 V vs. Na/Na⁺); (2) high metallic conductivity (2.5 × 10⁶ S·m⁻¹); and (3) high theoretical capacity of 660 mAh·g⁻¹ [6, 7]. Unfortunately, the utilization of Sb-based materials is limited by the large volume change from Sb to Na₃Sb (up to ~ 390%), which will cause inferior reversibility and rapid capacity decay [8]. Thus, suppression of volume expansion of Sb and prevention of powder shedding due to volume expansion are the key points to improve the electrochemical performance of Sb-based materials. As previously reported, nanoparticles are effective in reducing mechanical stress and greatly alleviating crushing problems during the charging and discharging process [9, 10]. But most traditional methods need high temperature, resulting in Sb particles being agglomerated [11]. Therefore, researchers need to find a suitable method to achieve high sodium storage performance of Sb-based materials. …