Reduced graphene oxide (RGO)-SnOx (x=0,1,2) nanocomposite as high performance anode material for lithium-ion batteries

摘要

Although, metal oxide-graphene nanocomposites and their applications in Li ion battery is a subject of intense investigation over the years, the synthesis of the composite that often needs high temperature processing along with expensive equipment are the major issues to overcome. We demonstrate a facile, low cost and room temperature synthesis of SnOX (x = 0,1,2) - reduced graphene oxide (RGO) nano-composite where concurrent formation of SnO2, reduction of SnO2 to SnOx nanoparticles and graphene oxide to reduced graphene oxide takes place in one pot in-situ chemical reduction process. Concentration of the reducing agent (NaBH4, 0 mol-0.06 mol) is varied to examine the effect on the formation of the nanocomposite as well as their electrochemical performance. The RGO-SnOx nanocomposite prepared by using 0.04 mol of reducing agent reveal better Li storage performance, stable capacitance (833 mAh g(-1) after 50 cycles, 767 mAh g(-1) after 100 cycles, current rate = 100mA g(-1)), and good rate capability (481 mAh g(-1) at -1 A g(-1)). The lithium ion diffusion coefficient of RGO-SnOx (0.04 mol) nanocomposite is estimated as 2.4 x 10(-10) m(2)s(-1) that is one/two order higher than other RGO-SnOx nanocomposites which promotes the Li ion transport in the composite. The synthesis procedure has a strong potential to be one of the universal method for the preparation of a variety of composites by the suitable variant in the synthesis protocol. (C) 2019 Published by Elsevier B.V.