Nano-Confined Tin Oxide in Carbon Nanotube Electrodes via Electrostatic Spray Deposition for Lithium-Ion Batteries

The development of novel materials is essential for the next generation of electric vehicles and portable devices. Tin oxide (SnO₂), with its relatively high theoretical capacity, has been considered as a promising anode material for applications in energy storage devices. However, the SnO₂ anode material suffers from poor conductivity and huge volume expansion during charge/discharge cycles. In this study, we evaluated an approach to control the conductivity and volume change of SnO₂ through a controllable and effective method by confining different percentages of SnO₂ nanoparticles into carbon nanotubes (CNTs). The binder-free confined SnO₂ in CNT composite was deposited via an electrostatic spray deposition technique. The morphology of the synthesized and deposited composite was evaluated by scanning electron microscopy and high-resolution transmission electron spectroscopy. The binder-free 20% confined SnO₂ in CNT anode delivered a high reversible capacity of 770.6 mAh g^-1. The specific capacity of the anode increased to 1069.7 mAh g^-1 after 200 cycles, owing to the electrochemical milling effect. The delivered specific capacity after 200 cycles shows that developed novel anode material is suitable for lithium-ion batteries (LIBs).