Solvothermal Synthesis of Molybdenum Disulfide/Reduced Porous Graphene Oxide Nanocomposite as High Performance Anode Material for Lithium Ion Battery

Abstract

Lithium ion batteries are widely used as power sources for portable electronic devices and hybrid electric vehicles. Electrode materials with high lithium storage capacity have been studied to meet the requirements of these applications. Among these materials, molybdenum disulfide (MoS2) is one of promising anode material to replace commercial graphite anode because intercalation of a MoS2 with 4 Li+ ions results in a higher storage capacity for MoS2 (670 mA h g-1) than commercial graphite anodes (372 mA h g-1). Although MoS2 has a high theoretical capacity than graphite as an anode material for Lithium-ion battery, its intrinsic poor electrical/ionic conductivity decreases rate property and lithium storage capacity. In my thesis, I prepared MoS2/reduced porous graphene oxide (rPGO) composite by solvothermal method to complement conductivity and improve lithium storage properties of MoS2. PGO was synthesized by convenient, low-cost, and mass-producible nitric acid treatment method. Due to its enlarged surface area and porous structure, MoS2/rPGO sample exhibited improved capacity and cyclic stability than other MoS2/reduced graphene oxide (rGO) and MoS2 nanoparticle samples. After 100 cycles, MoS2/rPGO electrode shows improved capacity of 932 mA h g-1 while capacity of MoS2/rGO electrode is 395 mA h g-1 at 200 mA g-1.