Arc-discharge synthesis of dual-carbonaceous-layer-coated tin nanoparticles with tunable structures and high reversible lithium storage capacity

Abstract

Sn@C nanocomposites are of great interest for use as high-capacity anode materials for lithium ion batteries (LIBs). In this paper, we describe a facile arc-discharge method to produce carbon-coated tin-nanostructured composites by reducing SnO₂ in CO gases. Metallic Sn species are homogeneously coated in dual carbonaceous layers and effectively confined within the nanostructures. The resulting composites are used as anode materials for LIBs and exhibit excellent cyclability of over 200 cycles along with high specific capacities (1220 mA h g⁻¹ at a current density of 372 mA g⁻¹ and 600 mA h g⁻¹ at high current densities up to 3720 mA g⁻¹). By tuning the content of tin precursor, a unique morphology conversion from spherical Sn nanoparticles embedded in the carbon framework to Sn rods that can regulate the electrochemical property has been observed. Most of all, such a Sn@C composite is a very promising anode material for LIBs for practical applications.