Three-dimensional MoS2/rGO nanocomposites with homogeneous network structure for supercapacitor electrodes

Abstract

Molybdenum disulfide/graphene (MoS2/rGO) nanocomposites are a promising candidate for energy storage materials. However, it is still a challenge to uniformly disperse MoS2 on rGO nanosheets, which the performance mainly depends on. In this work, we demonstrate a novel method to synthesize the three-dimensional (3D) MoS2/rGO nanocomposites by the high-gravity reactive precipitation in a rotating packed bed (RPB) reactor combined with the hydrothermal method. The prepared nanocomposites have higher purity and larger specific surface area than that prepared in the traditional stirred tank reactor (STR). More importantly, MoS2 is uniformly and densely dispersed on rGO nanosheets, resulting in the formation of an even 3D network structure and contributing to the achievement of excellent energy storage performance. The specific capacitance of the nanocomposites reaches 294 F g−1 at a scan rate of 20 mV s−1, which is obviously higher than that of pure MoS2 (122 F g−1) and rGO (23 F g−1). The calculated energy density and power density are 57 Wh kg−1 and 50 W kg−1, respectively. Moreover, the preparation process is environmentally friendly, controllable and suitable for a large-scale production, which is significantly important for the development of the electrode materials applied in the supercapacitors.