Eco-friendly prepared mesoporous carbon encapsulated SnO₂ nanoparticles for high-reversible lithium-ion battery anodes

Tin oxide (SnO₂) with porous carbon has attracted significant interest as a negative electrode material for lithium-ion batteries (LIBs). High cost and complex carbon coating preparation procedures are hinder in the commercialization of carbon based SnO₂ anodes. In this work, we designed and synthesized SnO₂ nanoparticles encapsulated mesoporous carbon composite (SnO₂@MPC) derived from low cost and easily available green microalgae by the simple hydrothermal process followed by Iron oxide etching. The BET analysis confirmed the SnO₂@MPC composite material contains highly porous carbon matrix with high surface area of 798.9 m² g⁻¹. The SnO₂@MPC delivered a high initial capacity of 1042 mAh g⁻¹ and showed a reversible capacity up to 180 cycles at a 0.1 C, which indicate that the porous carbon covering up SnO₂ nanoparticles alleviates the stress from the volume expansion. In addition, the porous carbon enhances the overall electrical conduction of the electrode and facilitate the electrolyte pentation, resulting in the better rate capability compared to bare SnO₂ nanoparticles (SnO₂_NP).