Synthesis of Ag nanoparticle-decorated MgO hollow spheres for enhancing photocatalytic activity

Ag nanoparticle-decorated MgO hollow spheres and MgO hollow spheres were fabricated by a facile hydrothermal method using Ag@carbon and carbon microspheres as templates, respectively. The obtained products were identified by several characterization techniques. The photocatalytic activities of the prepared samples were evaluated by degradation of RhB dye in an aqueous medium. After 120 min of UV illumination, above 98% of Rhodamine B was degraded in the presence of MgO/Ag hollow spheres, while only 48% is degraded within the same time using MgO hollow spheres. The higher specific surface area of MgO/Ag hollow spheres with respect to MgO hollow spheres along with its longer photogenerated charge carrier lifetime cause MgO/Ag hollow spheres to exhibit superior RhB dye photodegradation activity in comparison to MgO hollow spheres. The presence of Ag in MgO/Ag hollow spheres creates a Schottky junction between silver and magnesium oxide, resulting in efficient charge separation and enhancing the rate of photocatalytic reactions.