Layered SnS sodium ion battery anodes synthesized near room temperature

Abstract

In this report, we demonstrate a simple chemical bath deposition approach for the synthesis of layered SnS nanosheets (typically 6 nm or ~10 layers thick) at very low temperature (40 °C). We successfully synthesized SnS/C hybrid electrodes using a solution-based carbon precursor coating with subsequent carbonization strategy. Our data showed that the ultrathin carbon shell was critical to the cycling stability of the SnS electrodes. As a result, the as-prepared binder-free SnS/C electrodes showed excellent performance as sodium ion battery anodes. Specifically, the SnS/C anodes delivered a reversible capacity as high as 792 mAh·g−1 after 100 cycles at a current density of 100 mA·g−1. They also had superior rate capability (431 mAh·g−1 at 3,000 mA·g−1) and stable long-term cycling performance under a high current density (345 mAh·g−1 after 500 cycles at 3 A·g−1). Our approach opens up a new route to synthesize SnS-based hybrid materials at low temperatures for energy storage and other applications. Our process will be particularly useful for chalcogenide matrix materials that are sensitive to high temperatures during solution synthesis.