title: Synthesis of hollow ellipsoidal silica nanostructures using a wet-chemical etching approach.
abstract: We have utilized wet-chemical etching of ellipsoidal silica nanoparticles (ESNs) to form silica nanoshells of a range of elliptical morphologies, with the thicknesses of the ellipsoidal silica nanoshells (ESSs) controlled through variation of synthesis conditions. A mechanism has been proposed to explain how the nanoshells are formed, and we demonstrate that the porosity of the silica ellipsoid plays a role in generating silica shells. Our self-templated, wet-etching approach is an attractive alternate procedure to the approaches presently in existence for the following reasons: (i) it is a facile, one-step process that directly produces ellipsoidal silica nanoshells, while overcoming barriers (such as requirement of removing a solid-core template seed) utilized in many reported chemical etching studies; (ii) it results in ellipsoidal silica nanostructures with dimension less than 100 nm; (iii) with an appropriate etchant, the roughness of the silica shells can be well-controlled; and (iv) it results in tunable, uniform size particles with controllable shell thicknesses. Moreover, the silica materials with the unique structures might be adjusted to meet practical application requirements.
authors.affiliation: Department of Chemistry, The City College of the City University of New York, New York, NY 10031, United States.
authors.forename: Henan
authors.initials: H
authors.lastname: Zhang
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.forename: Yueru
authors.initials: Y
authors.lastname: Li
authors.forename: Teresa J
authors.initials: TJ
authors.lastname: Bandosz
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Akins
mesh_terms: D001894:Borohydrides / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D054118:Nanospheres / Q000737:chemistry*; D010316:Particle Size; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001894:Borohydrides; D012822:Silicon Dioxide; C025364:sodium borohydride