Building hierarchically hybridized carbon to anchor SnO2 nanoparticles for greatly enhanced lithium storage

Tin oxide (SnO ₂ ) is one of the promising anode materials for lithium-ion batteries (LIBs) owing to its high specific capacity and low cost. However, the sluggish Li ⁺ storage kinetics and huge volume change seriously restrict its rapid charge/discharge capability and cycle stability. Herein, we demonstrate a novel structure of ultrafine SnO ₂ nanoparticles anchored on carbon nanotubes foam with subsequent carbon coating (SnO ₂/NCF-CNTs@C). In which, NCF-CNTs can served as conductive substrates for SnO ₂ nanoparticles, promoting the transfer for both electrons and ions. In addition, the carbon coating layer can prevent the falling and pulverization of SnO ₂ nanoparticles and meanwhile alleviate the volume expansion during the electrochemical processes. Therefore, the SnO ₂/NCF-CNTs@C hybrids show excellent rate and cycle performance, which achieves a reversible capacity of 1059.2 mA h g ⁻¹ at 0.1 A g ⁻¹ and 518.2 mA h g ⁻¹ at 5.0 A g ⁻¹ and 554.9 mA h g ⁻¹ can be remained after 500 cycles at 2.0 A g ⁻¹.