Thapanee Sarakonsri

Abstract:

Highly distributed metal/alloy nanoparticles in carbon matrices is the promising anode microstructure that can enhance both energy density and cycle life for the next generation lithium-ion battery. In this report, high theoretical capacity metal/alloys such as Sn, SnSb, and SnS nanoparticles can simply be synthesized on carbon surface via chemical method at low temperature. Sn-C and SnSb-C were obtained from the reduction reaction of metal ions with sodium borohydride in ethylene glycol solvent; while SnS-C was prepared from a reflux method at 200°C in ethylene glycol. The carbon surface area affected by the amount and size of metal/alloy formation was studied by using different types of carbon materials, which were natural graphite (NG), artificial graphite (AG), mesocarbonmicrobead (MCMB) and graphene. The amount of Sn varied from 10-20% by weight in Sn-C and SnS-C, and 10-40% in SnSb-C, while the amount of Sb was maintained at 10% and S varied from 10-20%. Materials characterization by XRD and TEM techniques revealed Sn, SnSb, SnS phases appeared along with C phase. The highest Sn content and lowest Sn particles size were obtained from Sn-graphene samples. The preferred SnSb phase with ratio Sn:Sb of 1:1 was obtained when the weight of the reactants was 10 %wt of Sb, 20 %wt of Sn, and 70%wt of artificial graphite. SnS-C shows different morphology as high surface area flower like microstructure.