Fabrication of submicron Cu2O hollow spheres in an O/W/O multiple emulsions

In the current paper, the submicron Cu2O hollow spheres composed of small Cu2O nanoparticles of 22 nm in size were successfully prepared via using a multiple emulsion (O/W/O) system as the template. In this system, the interior oil phase was used as the core and exterior oil phase as the dispersion medium to prevent the product from aggregating; the reactants are dissolved in interim water layer. The liquid-droplet of the multiple emulsions plays a template and space-limiting role in addition to preventing the product from aggregation.