Facile two-step synthesis of innovative anode design from tin-aminoclay (SnAC) and rGO for Li-ion batteries

Abstract

A tin-aminoclay/reduced graphene oxide (SnO2-SnAC/rGO) electrode with significantly enhanced electrochemical performance was successfully fabricated by a facile two-step method entailing microwave treatment (1st step) and heat treatment (2nd step) synthesis processes. In step 1, the complete reduction of GO to rGO by microwave ensures the removal of most oxygen-containing functional groups on the material surface leading to improvement of its electrical conductivity along with the formation of SnO2 dots of 3–4 nm diameter. In step 2, the tin crystals are formed more stably in the SnAC/rGO framework by the heat-treatment process under Argon (Ar) gas via the direct conversion process of Sn2+ active sites within the SnAC structure. With this two-step process, the synthesized material possesses many unique synergistic effects, all leading to beneficial features (i.e., improved specific capacity, high rate capability, and long cycle life stability compared with SnO2-SnAC and pure rGO electrodes) for application to battery electrodes. Especially, SnO2-SnAC/rGO-500 °C (1:1) exhibits outstanding performance in terms of cyclic performance (650 mAh g−1 after 100 cycles at 100 mA g−1) and rate capability. © 2020 Elsevier B.V.