One-Step Synthesis of Molybdenum Disulfide and Mechanism for Effective Adsorption of Cationic Dyes

Graphical This paper reports the one-step synthesis of 1T-MoS₂ nanosheets using a simple hydrothermal method at 140 °C. The highest adsorption abilities for methylene blue and rhodamine b are 605 and 795 mg g⁻¹, respectively. This paper reports on the one-step synthesis of molybdenum disulfide (MoS 2 ) nanosheets with excellent adsorption properties for cationic dyes using a simple hydrothermal method. Compared with 2H-MoS 2 prepared at 220 °C, 1T-MoS 2 prepared at 140 °C showed better adsorption of cationic dyes, with highest adsorption abilities of 605 and 795 mg g⁻¹ for methylene blue and rhodamine b, respectively. The adsorption process follows a pseudo second-order kinetic model, which indicates that the process is mainly controlled by chemisorption. At the same time, the Langmuir isotherm model is more suitable for describing the adsorption process, suggesting a monolayer adsorption on a homogeneous surface of 1T-MoS 2 . Adsorption equilibrium times were observed at 1–6 h in the initial dye concentration range of 100–400 mg/L. The zeta-potential and XPS results suggest that 1T-MoS 2 possesses a negatively charged surface and abundant oxygen-containing functional groups, making it more effective in adsorbing cationic dyes. The excellent adsorption performance of 1T-MoS₂ provides fresh perspectives for the development of MoS₂-based adsorbents.