The novel and facile preparation of multilayer MoS2 crystals by a chelation-assisted sol-gel method and their electrochemical performance

Abstract

Multilayer molybdenum disulfide (MoS2) was facilely prepared by a chelation-assisted sol-gel method with ammonium molybdate tetrahydrate ((NH4)6Mo7O24·4H2O) as the molybdenum source, thioacetamide (CH3CSNH2) as the sulfur source and diethylenetriamine pentaacetic acid (Dtpa) as the chelating agent, subsequently followed by high-temperature calcination. The chelating agent Dtpa ingeniously mediated the chelation reaction of the system and promoted the formation of a monolithic gel. The hexagonal MoS2 crystal (2H-MoS2) with good crystallinity precipitated after calcination at 1000 °C with the Mo and S mass ratio of 1 : 3. The adjustable MoS2 layers stacked together to form MoS2 flakes, and these flakes aggregated to construct crystalline MoS2 particles. The electrochemical tests showed the possibility of as-prepared MoS2 crystals applied as a negative electrode for lithium ion batteries.