Hydrothermal Synthesis And Electrochemical Properties Of Amorphous MoS₂

MoS2nanomaterials have attracted a worldwide interest because of their uniquestructural characteristics and their potential applications in many fields. The structure of MoS2determines its performance. Therefore, exploring an effective synthetic method to control themorphology of MoS2becomes a trend. We successfully synthesized the rod-like and hollowMoS2microspheres. A series of investigations including the preparation, calcination andelectrochemical performance of MoS2have been performed in this dissertation.1. Rod-like and hollow microspherical MoS2were synthesized via a facile hydrothermalmethod at different reaction conditions using MoO3as the molybdenum source. Theformation of rod-like MoS2was result from the assembly and non-assembly, respectively.MoS2hollow microspheres with the diameter of1–2μm and the thickness of about100nmwere obtained. Based on a series of comparable experiments, it was found that the amount ofNH2OH·HCl played a key role in the formation of MoS2hollow microspheres. Themachenism of hollow MoS2microspheres was controlled by the Kirkendall effect.2. By increasing the calcination temperature, the crystallization rate of the crystal wasmarkedly accelerated, which confirmed that the most important factor to affect the graingrowth rate was the calcination temperature. It was found that when the sample was calcinedat900oC for2h, a better crystalline MoS2could be obtained. The calculation experimentproved that MoS2crystalline grain growth activation energy was50～60kJ/mol. Combinedwith the crystal growth kinetics, it was concluded that the grain growth was controlled by thegrain boundary diffusion mechanism.3. MoS2powder could be used as the anode material for lithium ion batteries. Theelectrochemical properties of MoS2nanomarerials were detected by cyclic voltammetry andgalvanostatic charge-discharge tests. The cyclic performance showed that the charge capacityof two kinds of MoS2nanomarerials obviously decreased with the increasing of the cyclenumber, from about500mAh/g for the first cycle to200mAh/g at the40th cycle.