Crystalline Carbon Hollow Spheres, Crystalline Carbon−SnO₂\nHollow Spheres, and Crystalline SnO₂ Hollow Spheres:  Synthesis\nand Performance in Reversible Li-Ion Storage

Abstract

A few types of crystalline hollow structures, crystalline carbon hollow spheres (750 nm), crystalline\ncarbon hollow spheres with encapsulated or decorated 1−3 nm SnO₂ nanoparticles, and crystalline SnO₂\nhollow spheres (200−300 nm) synthesized by various methods, have been evaluated for reversible Li⁺\nstorage. The experimental results showed noticeable improvements in a number of performance areas\nsuch as specific capacity, rate capability, and cyclability. The improvements could be attributed to a high\ndegree of crystallinity, which increases the electronic conductivity, and the facile transport of Li ions in\na hollow shell with nanoscale thickness, which significantly shortens the solid-state diffusion length.