title: Silica encapsulated CdS tabular nanocomposites via a template directed agglomeration mechanism.
abstract: Silica coated CdS tabular nanocomposites were synthesized through precipitation of CdS nanoparticles in octylamine/water bilayer system followed by in situ hydrolysis of tetraethoxylsilicate (TEOS) precursor. Face diameter of the nanoplatelets was in the range of 50-250 nm with a variable thickness (3 to 25 nm) dictated by octylamine content or R ratio ([water]/[octylamine]). A uniform SiO2 outer shell of about 15 nm was observed regardless of the size of the high aspect ratio CdS nanoplatelets, which appeared to be agglomerated primarily owing to the confined bilayer template. Morphology and microstructure of the CdS/SiO2 tabular nanocomposites were characterized using atomic force microscope (AFM) and high resolution transmission electron microscope (HRTEM). A noticeable enhancement in absorbance for the UV-vis spectra was observed due to the SiO2 coating layer. Growth mechanism of nanocomposite platelets and potential applications associated with this anisotropic nanocomposite are discussed.
authors.affiliation: NSF Particulate Materials Center Materials Research Institute and Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Sollenberger
authors.forename: Ying
authors.initials: Y
authors.lastname: Yuan
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Yosenick
authors.forename: James H
authors.initials: JH
authors.lastname: Adair
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D019187:Cadmium Compounds; D046911:Macromolecular Substances; D018036:Selenium Compounds; D012822:Silicon Dioxide; C058667:cadmium selenide