Using Carbons As Scaffolds for Morphological Control of Metal Oxide Nanoparticles

Metal oxide submicron particles with a yolk-shell structure are achieved utilizing a facile aerosol-based process on the basis of the competitive mechanisms of sucrose carbonization and the precipitation of soluble metal salts followed by calcination. Sucrose carbonization and metal salts precipitation can be easily controlled to occur sequentially in an aerosol droplet by controlling operating temperature, leading to large amounts of metal salts precipitating on the external surface with a small portion of metal salts being trapped inside of the carbonized particles. Further calcination of particles can remove carbon scaffold and result in formation of yolk-shell structure metal oxide. The void between shell and core allows loading of active materials. Further treatment of metal oxide provides particles with opportunity to possess other desired properties such as magnetism. This work is supported by the National Science Foundation.