Three-Dimensional Coral-Like Structure Constructed of Carbon-Coated Interconnected Monocrystalline SnO2 Nanoparticles with Improved Lithium-Storage Properties

The applications of alloying/dealloying materials as anode for LIB electrode are hindered by its dramatic volume variations and sluggish kinetics. Herein, to overcome these challenges, we report a facile and scalable approach fabricating coral-like SnO2/C composite electrodes through a top-down strategy followed by a sol-gel carbon-coating method. During the synthesis, well-defined SnS2 nanoflowers and dopamine serve as structural template and carbon source for integrating the desired structure. The three-dimensional coral-like SnO2/C composite exhibits a high reversible capacity of 648mAhg(-1) after 50 electrochemical cycles and a low capacity fading of 0.778% per cycle from the 2nd to the 50th cycle, demonstrating an outstanding cycling stability. It also shows a discharge capacity of 1294, 784, 658, 532, and 434mAhg(-1) at a specific current of 100, 200, 500, 1000 and 2000mAhg(-1), respectively, and retains a specific capacity of 719mAhg(-1) when the specific current goes back to 100mAg(-1), displaying an excellent rate capability. Compared to SnS2 nanoflowers and bare interconnected SnO2 nanoparticles anode, the optimized coral-like SnO2/C composite shows significantly improved electrochemical performances in terms of rate capability and cycling reversibility, demonstrating great potential as superior anodes in next-generation lithium ion batteries.