Enhanced dyes removal properties of hollow SnO2Microspheres and SnO2@C composites

Abstract

SnO2 hollow microspheres are controllably synthesized with the assistance of sulfonated polystyrene (sPS) colloidal spheres as hard templates. Via the interaction between ions of Sn2+ from the precursor SnSO4 which are in ethanol–aqueous medium and -SO3H ions on the template surface, sPS spheres-SnO2 precursor (sPS@SnO2) core–shell composite microspheres are prepared through a one-step hydrothermal method. The hollow SnO2 microspheres can be obtained after removal of the sPS microspheres by calcination in air. Furthermore, SnO2@C composite hollow spheres were fabricated with the further carbonization of the sPS@SnO2@glucose composite microspheres. By scanning electron microscopy, transmission electron microscopy, and BET measurements; the morphology, specific surface area, and the core–shell structure were investigated. Application for hollow and composite spheres in sewage treatment of dye solution was evaluated. SnO2 hollow spheres and SnO2@C composite hollow spheres are adsorbent materials which can adsorb Congo red (CR), basic fuchsine, and methylene blue in solutions. SnO2 hollow spheres can be simulated adsorption process of CR solution under acidic conditions. This process is regenerated and the regeneration performance is stable. The adsorption properties of SnO2@C composite hollow spheres are improved than SnO2 hollow spheres and they could be widely applied to sewage treatment.