Hydrothermal synthesis of flower-like molybdenum disulfide microspheres and their application in electrochemical supercapacitors

Abstract

Three-dimensional flower-like molybdenum disulfide microspheres composed of nanosheets were prepared by a hydrothermal method using ammonium molybdate as the molybdenum source and thiourea as the sulfur source. Structural and morphological characterizations were performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy and X-ray photoelectron spectroscopy (XPS). The electrochemical properties of MoS2 electrode were studied by performing cyclic voltammetry (CV), galvanostatic charge-discharge analysis and electrochemical impedance spectroscopy (EIS). When used as an electrode material for supercapacitor, the hybrid MoS2 showed a high specific capacity of 518.7 F g-1 at a current density of 1 A g-1 and 275 F g-1 at a high discharge current density of 10 A g-1. In addition, a symmetric supercapacitor composed of MoS2 as positive and negative electrodes was prepared, which exhibited a high energy density of 12.46 W h kg-1 at a power density of 70 W kg-1 and still maintains an impressive energy density of 6.42 W h kg-1 at a large power density of 7000 W kg-1. The outstanding performance of the MoS2 electrode material indicates its great potential for applications in high-performance energy storage systems.