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.