Abstract

3D macroscopic tin oxide/nitrogen-doped graphene frameworks (SnO2/GN) were constructed by a novel solvothermal-induced self-assembly process, using SnO2 colloid as precursor (crystal size of 3–7 nm). Solvothermal treatment played a key role as N,N-dimethylmethanamide (DMF) acted both as reducing reagent and nitrogen source, requiring no additional nitrogen-containing precursors or post-treatment. The SnO2/GN exhibited a 3D hierarchical porous architecture with a large surface area (336 m2g-1), which not only effectively prevented the agglomeration of SnO2 but also facilitated fast ion and electron transport through 3D pathways. As a result, the optimized electrode with GN content of 44.23% exhibited superior rate capability (1126, 855, and 614 mAh g-1 at 1000, 3000, and 6000 mA g-1, respectively) and extraordinary prolonged cycling stability at high current densities (905 mAh g-1 after 1000 cycles at 2000 mA g-1). Electrochemical impedance spectroscopy (EIS) and morphological study demonstrated the enhanced electrochemical reactivity and good structural stability of the electrode.