Molten Salt Synthesis of Tin Oxide Nanorods: Morphological and Electrochemical Features

Abstract

This article reports the nonhydrothermal synthesis of SnO2 nanorods at moderate temperatures (320 or 700 °C), and the application of these nanorods as a Li storage compound for Li-ion batteries. The 15 nm diameter high aspect ratio (∼50−100) SnO2 nanorods prepared at 700 °C were fabricated as Li-ion battery anodes and tested. They exhibited good capacity (∼700 mAh/g nominal in the 5 mV to 1 V range) and extended cyclability for a tin-based anode. More interestingly was the observation of a capacity of ∼1100 mAh/g in the 5 mV to 2 V window that exceeds the theoretical capacity of SnO2. SEM and TEM characterizations revealed substantial morphological changes in the nanorods during cycling. A few possible reasons for the high capacity and the morphological changes are provided.