Facile preparation of a monodispersed CuO yolk-shelled structure with enhanced photochemical performance

Tailored design of photocatalysts with complicated hollow structures is of great importance for promoting environmental remediation. Herein, a monodispersed CuO yolk-shelled structure is synthesized for the first time by simple calcination treatment of a pre-synthesized Cu-EG (ethylene glycol) complex with yolk-shelled structure using a simple, environmentally friendly and glycerol-mediated solvothermal method. Ostwald ripening is the main formation mechanism for the yolk-shelled structure. Such CuO yolk-shelled structures show excellent photocatalytic activity, which is 3.65 times faster than that of the commercial CuO powders and is one of the highest reported photocatalytic activities to date in the CuO nanomaterials for the degradation of rhodamine B (RhB) under visible light irradiation. Such a preferable photocatalytic activity is mainly attributed to the unique yolk-shelled structure, which can enable higher multiple light reflections and scattering between the outer spherical shell and the interior core compared with commercial CuO powders, to provide a more efficient way to enhance light-harvesting efficiency.