Facile synthesis of ultrasmall tin oxide nanoparticles embedded in carbon as high-performance anode for lithium-ion batteries

Tin oxide (SnO2) has received great attention as promising anode for lithium ion batteries because it offers a high theoretical capacity (ca. 782 mAh g−1 for Li4.4Sn) and a safe discharge potential versus Li/Li+ in comparison to commercialized graphite anodes, whereas it also suffer from the drawbacks of the huge volume change and low electronic conductivity during lithiation/delithiation processes. Herein, we have prepared a SnO2/C composite of ultrasmall SnO2 nanoparticles (∼6 nm and ∼59.4% by weight) embedded in carbon matrix (denoted as SnO2/C-59) by a facile hydrothermal and subsequent carbonization approach. In this peculiar architecture, uniform distribution of SnO2, and electronic conductivity of carbon matrix, which can effectively solve the problems of pulverization, loss of electrical contact and particle aggregation during cycling, therefore contributing to excellent lithium storage and cycling stability. A reversible capacity of 839.1 mAh g−1 is obtained at 200 mA g−1 after 217 cycles. More importantly, 712.8 mAh g−1 can be obtained at 800 mA g−1 even after 378 cycles.