Carbon-Coated Ordered Mesoporous SnO₂ Composite Based Anode Material for High Performance Lithium-Ion Batteries

Recently, tin oxide (SnO₂) has received significant attention for use as an anode material for next generation lithium-ion batteries (LIBs) owing to its high theoretical capacity (782 mAh g⁻¹), which is more than twice of that of the commercialized graphite (372 mAh g⁻¹). Several additional advantages, such as low cost, environmental friendliness, easy fabrication and natural abundance improve its promise. Although the theoretical capacity of SnO₂ is high, volume expansion during cycling causes issue with cycling stability. In this study, an ordered mesoporous SnO₂ was synthesized using a hard template (SBA-15), such that its mesoporous structure can buffer SnO₂ particles from cracks caused by volume expansion. It can also allow effective electrolyte infiltration to ensure better reactivity of the active material with Li⁺ ions. The capacity of synthesized mesoporous SnO₂ improved to 218.4 mAh g⁻¹ compared regular SnO₂ nanoparticles (69.6 mAh g⁻¹) after 50 cycles at a rate of 0.1 C. Furthermore, carbon-coated mesoporous SnO₂ enhanced capacity retention upon cycling (844.6 mAh g⁻¹ after 50 cycles at 0.1 C) by insulating and preventing the cracking of the active material during lithiation and delithiation.