Dual carbon protected ultrafine SnO2 nanoparticles with Sn–C interface for robust lithium storage

Stannic oxide (SnO 2 )-based lithium-ion batteries (LIBs) have garnered tremendous attention due to their high theoretical capacity and suitable lithium ion insertion potential. However, their widespread applications have been hindered by severe electrode degradation caused by substantial volume expansion of SnO 2 . In this study, we embedded amorphous carbon encapsulated ultrafine SnO 2 nanoparticles on hollow macroporous carbon (AC@SnO 2 /HMC) as a superior anode material for LIBs. The unique Sn–C interface and dual carbon protection layers effectively mitigated SnO 2 nanoparticle agglomeration and volume expansion, reinforcing the cycling stability. Additionally, the capacitive contribution from amorphous carbon significantly improved the reversible capacity and rate capability. As such, the resulting AC@SnO 2 /HMC electrode exhibited high capacity (1828 mAh g −1 after 200 cycles at 0.1 A g −1 ), excellent rate capability (1017.6 mAh g −1 at 1 A g −1 ), and outstanding cycling performance (792.1 mAh g −1 after 880 cycles at 2 A g −1 ), surpassing previously reported SnO 2 -based anodes. Furthermore, the AC@SnO 2 /HMC-based Li-ion full cell demonstrated a remarkable capacity of 566.3 mAh g −1 at 0.2 A g −1 after 200 cycles. This study offers valuable insights into the development of advanced SnO 2 -based anodes for LIBs and beyond, highlighting their potential for future advancements in battery technology.