High-yield synthesis of single-crystal silicon nanoparticles as anode materials of lithium ion batteries via photosensitizer-assisted laser pyrolysis

Abstract

Single crystal silicon nanoparticles (Si-NPs) of 20 nm were produced via laser pyrolysis with a virtually complete conversion from SiH₄ to Si-NPs. SF₆ was used as the photosensitizer to transfer laser beam energy to silicon precursors, dramatically enhancing crystallinity of Si-NPs and their production efficiency. By using their well-developed crystalline structure, the directional volume expansion of Si-NPs was confirmed during lithiation. Lithiation/delithiation kinetics of our Si-NPs was superior to that of their amorphous counterparts due to the footprinted Li⁺ pathways formed during amorphization.