Electrochemical growth of two-dimensional tin nano-platelet as high-performance anode material in lithium-ion batteries

Abstract

A template free, single-step process is developed for fabrication two-dimensional tin nano-platelets by electrochemical deposition in the presence of Triton X100 (TX100). Electrochemical studies combined with structural characterization revealed that during electrodeposition, TX100 molecules adsorb preferentially on {022} planes of Sn and highly anisotropic growth promotes in [200] direction which results in the formation of platelet morphology. The deposited platelets exhibit a high aspect ratio of 30 (width to thickness) and thickness of 25±5nm that uniformly covered the substrate with a high platelet density of 9×108cm−2. The electrochemical performance of nano-platelets for lithium storage was studied in detail and compared with other morphologies of tin. Tin nano-platelets exhibited high reversible capacity and excellent cycling performance, the capacity was maintained at 820mAhg−1 for 100 cycles and more, far superior to the other structures. Excellent rate capability was also observed for nano-platelets up to 5 C, with the ability to be operated at 20 C without damage. The superior electrochemical performance of tin platelets is mainly attributed to its two-dimensional structure that efficiently distributes strain, allowing high mechanical stability even after 100 cycles, as confirmed by Scanning Electron Microscopy (SEM).