Rattle-type Carbon–Alumina Core–Shell Spheres: Synthesis and Application for Adsorption of Organic Dyes

Abstract

Porous micro- and nanostructured materials with desired morphologies and tunable pore sizes are of great interests because of their potential applications in environmental remediation. In this study, novel rattle-type carbon–alumina core–shell spheres were prepared by using glucose and metal salt as precursors via a simple one-pot hydrothermal synthesis followed by calcination. The microstructure, morphology, and chemical composition of the resulting materials were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N₂ adsorption–desorption techniques. These rattle-type spheres are composed of a porous Al₂O₃ shell (thickness ≈ 80 nm) and a solid carbon core (diameter ≈ 200 nm) with variable space between the core and shell. Furthermore, adsorption experiments indicate that the resulting carbon–alumina particles are powerful adsorbents for the removal of Orange-II dye from water with maximum adsorption capacity of ∼210 mg/g. It is envisioned that these rattle-type composite particles with high surface area and large cavities are of particular interest for adsorption of pollutants, separation, and water purification