Hollow Inorganic Spheres

This chapter focuses on the hollow oxide nanoparticles prepared by liquid-phase deposition methods. This chapter reviewed recent advances in the preparation of hollow oxide nanoparticles by liquid-phase deposition methods. Among hollow inorganic particles, silica-based particles are the most extensively studied because of their ease of synthesis, structural and compositional diversities, and wide range of applications such as in coatings catalysis, adsorption, and drug delivery system (DDS). Hollow silica particles can be synthesized by either templating or template-free methods. Hollow particles with various compositions, controlled shell structures, and controlled shapes and sizes have successfully been obtained by employing either template or template-free method, and many interesting properties arising from their unique structural features have been reported. Large-scale and low-cost production by environment-friendly processes promises practical applications in many fields.