Development of the SbOCl@NbSe Composite: The Impact of 2H-NbSe Nanoparticles on SbOCl and Their Application for the Removal of Cr(VI)/Fe(III) and Methyl Orange from Wastewater.

A potential adsorbent, SbOCl@NbSe composite, was generated from the SbOCl photocatalyst and 5 wt % layered 2H-NbSe nanoparticles for the highly effective removal of Cr(VI) and Fe(III) ions and methyl orange (MO) from aqueous solution, and a comparison was drawn against the precursors. SbOCl crystallites and NbSe nanoparticles were synthesized hydrothermally, and the composite was prepared by the incipient wetness impregnation technique. The crystal structure of SbOCl was determined by single-crystal X-ray diffraction (SCXRD) data. Powder X-ray diffraction (PXRD) study revealed the 2H phase of NbSe nanoparticles. Field emission scanning electron microscopy (FESEM) analysis confirmed the formation of the spherical-shaped NbSe nanoparticles from rod-shaped bulk 2H-NbSe. Morphological changes from the hexagonal to irregular prismatic shape were found upon the formation of the SbOCl@NbSe composite compared to pure SbOCl. Negative ζ-potential values indicated that electrostatic interactions were the predominant factor for the adsorption process. SbOCl@NbSe provided removal efficiencies of 99% for MO in 6 h, 96.52% for Cr(VI) within 2.5 h, and 92.43% for Fe(III) within 4 h of 10 mg/L initial concentration. The maximum adsorption capacities of the composite for MO, Fe(III), and Cr(VI) were found to be 66.56, 131.48, and 122.30 mg/g, respectively, as calculated using the Langmuir isotherm equation.