Preparation and adsorption capacity of porous MoS2 nanosheets

Abstract

Layered porous MoS₂ with high adsorption capacity was synthesized directly using molybdenum trioxide and potassium rhodanate as Mo and S sources in a facile hydrothermal method without any surfactant and sacrificial template. The influences of varying the hydrothermal temperature on the morphology and adsorptive properties of MoS₂ are discussed. As-prepared MoS₂ samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible spectrophotometry (UV-Vis), room-temperature photoluminescence spectroscopy (RT-PL), thermogravimetric analysis (TGA) and Brunauer–Emmet–Teller (BET) measurements. MoS₂ samples exhibited an optimal nanostructure, specific surface area and thermal stability when the hydrothermal temperature was 190 °C, and the layered porous structure is comprised of many thin nanosheets. In addition, the final adsorption capacities of the layered MoS₂ toward RhB, MB and MO were studied. The sample exhibited ultrafast adsorption for dye removal and could reach 163.0 mg g⁻¹, 499.0 mg g⁻¹ and 125.1 mg g⁻¹ at 420 min, respectively. The adsorption mechanism was also studied. The results indicate that layered MoS₂ structures possess a significant adsorption ability, which may be useful for further research and practical applications of the layered MoS₂ adsorbent in wastewater treatment.