In-situ high loading of SnO2 monocrystals in a tridimensional carbon network via chemical bonding for enhanced lithium storage performance.

Abstract SnO 2 monocrystals with an average particle size of ∼10 nm have been in-situ embedded in a tridimensional carbon network (marked as SnO 2 @C) with a high loading percentage of 39.5 wt%. The synthetic mechanism of SnO 2 @C nanocomposite is discussed. The X-ray photoelectron spectroscopies demonstrate probable chemical bonding between SnO 2 nanoparticles and the carbon framework for enhanced lithium storage performance of SnO 2 @C nanocomposite as an anode material for lithium ion batteries. The SnO 2 @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 SnO 2 material. The high lithium storage capacity of SnO 2 @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 SnO 2 @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 SnO 2 @C nanocomposite and the robustness of the carbon network, which significantly contributes to superior lithium storage performance. Graphical abstract Image 1 Highlights • SnO 2 monocrystals are in-situ embedded in a tridimensional carbon network. • SnO 2 @C nanocomposite delivers superior lithium storage performance at 55 °C. • Chemical bonding is introduced between SnO 2 nanoparticles and the carbon network. • TEM images demonstrate preserved nanostructure of cycled SnO 2 @C nanocomposite. [ABSTRACT FROM AUTHOR]