LAUSR

Abstract SnO2 monocrystals with an average particle size of ∼10 nm have been in-situ embedded in a tridimensional carbon network (marked as SnO2@C) with a high loading percentage of 39.5 wt%. The synthetic mechanism of SnO2@C nanocomposite is discussed. The X-ray photoelectron spectroscopies demonstrate probable chemical bonding between SnO2 nanoparticles and the carbon framework for enhanced lithium storage performance of SnO2@C nanocomposite as an anode material for lithium ion batteries. The SnO2@C anode material delivers an initial charge capacity of 844 mAh/g at 0.1 C, and can retain a specific capacity of 661 mAh/g after 700 electrochemical cycles at 1 C (1 C = 0.79 A/g), showing considerably improved cycling and high-rate performance as compared with the bare SnO2 material. The high lithium storage capacity of SnO2@C anode material can be attributed to electrochemical reversibility related to the reduction of SnO to Sn and corresponding re-oxidation process, according to a reversible redox pair at 1.10/1.25 V recorded in CV cycles. The SnO2@C anode also reveals outstanding cycling stability at elevated temperature, resulting in a remaining capacity of 512 mAh/g after 125 cycles at 1 C and 233 mAh/g after 300 cycles at 5 C at 55 °C, respectively. TEM/HRTEM images show desirable structural integrity of cycled SnO2@C nanocomposite and the robustness of the carbon network, which significantly contributes to superior lithium storage performance.