S@Fe(OH)3/MXene Composite as a High-Performance Cathode Material for Lithium–Sulfur Batteries

Recently, lithium–sulfur batteries have drawn the attention of a large number of scholars in battery research, owing to their high-energy density and theoretical specific capacity. However, sulfur cathodes’ volumetric expansion and shuttle effect hinder their application. The purpose of this research is to improve the electrochemical performance of lithium–sulfur batteries by designing and constructing S@Fe(OH)3/MXene. First, the one-step injection method was used to prepare flowerlike Fe(OH)3 with a trumpet-like surface. Second, S@Fe(OH)3 was formed through melting diffusion, loaded with sulfur. Subsequently, the electrostatic self-assembly technique was used to create the S@Fe(OH)3/MXene. The high conductivity of MXene improved the active site, which is conducive to polysulfide adsorption. The data reveal that the first discharge–specific capacity of the S@Fe(OH)3/MXene reached 1374.7 mAh g–1 under 0.1 C. Next, the batteries were cycled 200 times under a 1 C high rate, and their capacity retention was 88.4%. All of these data indicate that S@Fe(OH)3/MXene has achieved satisfactory electrochemical stability and cycle performance. The findings presented in this thesis enhance the current understanding of lithium–sulfur batteries.