Functionalized MoO₃ Nanosheets for High-Efficiency RhB Removal

2D nanostructured materials have been applied for water purification in the past decades due to their excellent separation and adsorption performance. However, the functional 2D nanostructured molybdenum trioxide (MoO₃)has rarely been reported for the removal of dyes. Here, functionalized MoO₃ (F-MoO₃) nanosheets are successfully fabricated with a high specific surface area (106 cc g^-1) by a one-step mechanochemical exfoliation method as a highly effective adsorbent for removing dyes from water. According to the Raman, X-ray photoelectron spectroscopy, Fourier transform infrared (FTIR), and selected area electron diffraction analysis, functional groups (hdroxyl groups, amide groups, amine groups and amino groups) are identified in the as-prepared F-MoO₃ nanosheets. The attached functional groups not only facilitate the dispersal ability of F-MoO₃ nanosheets but also enhance the adsorption capacities. Thus, the performance (up to 556 mg g^-1 when the initial concentration of Rhodamine B solution is 100 mg L^-1) of as-prepared F-MoO₃ nanosheets is almost two times higher than other reported MoO₃ materials. Furthermore, the FTIR spectra, isotherm, and several factors (e.g., adsorbent dosage and adsorbate dosage) are also systematically investigated to explore the adsorption mechanism. Therefore, this work demonstrates that the F-MoO₃ nanosheets are a promising candidate for wastewater treatment.