Superior Capacitive Performance Enabled by Edge-Oriented and Interlayer-Expanded MoS2 Nanosheets Anchored on Reduced Graphene Oxide Sheets

Performance of MoS2-based supercapacitors is severely restricted by the limited ionic intercalation in the MoS2 molecular interlayer gaps and the poor intrinsic electrical conductivity of MoS2. To tackle these challenges, high-density edge-oriented (EO) MoS2 nanosheets with an expanded interlayer spacing of 9.4 Å supported on reduced graphene oxide (rGO) sheets are synthesized with the assistance of microwave heating. Using the edge-oriented and interlayer-expanded (EO&IE) MoS2/rGO as active electrode materials of capacitors, the specific capacitance can reach 346.5 F g–1 at a scan rate of 1 mV s–1, which is higher than the values of most reported supercapacitors using various MoS2/graphene composites. The enhanced capacitance originates from the fast and easy intercalation of ions in the supported EO&IE MoS2 nanosheets, facilitated by high electrical conductivity of the rGO supporting sheets as well as the edge-oriented geometry and expanded interlayer spacing of the MoS2 nanosheets.