Ultrathin MoS2 nanosheets hybridizing with reduced graphene oxide for high-performance pseudocapacitors

Abstract

Layered molybdenum disulfide (MoS2) is a promising candidate of electrode material for supercapacitors due to its intercalation chemistry and high theoretical capacitance, but still suffers limited practical performances arising from the low electroactive area and sluggish charge transfer kinetics. Herein, we report the few-layered MoS2 nanosheets hybridizing with reduced graphene oxide (MoS2/rGO) which present high specific capacitance of 361 F g−1 at 5 mV s−1, good rate capability and long-life stability in 1.0 mol L−1 H2SO4. The symmetric supercapacitor exhibits high energy density of 23.0 Wh kg−1@0.37 kW kg−1 and 5.2 Wh kg−1@62.0 kW kg−1, along with high cyclability. The excellent electrochemical performance is attributed to the much improved conductivity, active sites and redox kinetics owing to the hybridization, which leads to the predominant capacitive behavior as demonstrated by the detailed analysis on the charge transfer kinetics. This study demonstrates a simple strategy to develop hybrid electrodes of layered materials and nanocarbons for high-efficient energy storage.