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

Abstract 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.