ABSTRACT

Silica spheres provide large specific area and uniformity, and hence, these are used as a catalyst, adsorbent, and host materials. These spheres have large applications in chromatography and cosmetics. Hollow mesoporous nanospheres are used in drug delivery. Nanocoated nanoparticles are used in optics, optoelectronics, chemical engineering, pharmaceutics, etc. and have high catalytic activities for hydrogenation, hydroformylation, carbonylation, etc. Surfactants and electrolytes have profound effect on the catalytic properties of nanoparticles on the silica sphere. Synthetic approach has been devised to convert Stöber silica spheres into mesoporous silica spheres. Silica spheres can be synthesized under both acidic and basic conditions. Various templating approaches have been adopted to synthesize the porous materials.