COLL 331 |
| Vinit Murthy1, Rohit K. Rana1, Jie Yu1, and Michael S. Wong2. (1) Department of Chemical Engineering, Rice University, P.O. Box 1892, Houston, TX 77251-1892, (2) Department of Chemical Engineering and Department of Chemistry, William M. Rice University, 6100 Main St., MS-362, Houston, TX 77251-1892 |
| There has been a revived interest in the synthesis of inorganic hollow microspheres (submicron and micron diameters) for potential use in applications that involve encapsulation or release. Chemical approaches to hollow spheres include sacrificial core methods, interfacial syntheses, and surfactant self-assembly (to form vesicles). We present a new technique in which micron-sized inorganic hollow spheres can be fabricated as easily as organic vesicles through the use of positively-charged polymers (such as poly-L-lysine) and nanoparticles (NPs, such as those of Au and SiO2). Under ambient conditions in aqueous medium, the polymer combines electrostatically with gold NPs to form a floc intermediate around which SiO2 NPs absorb to form the shell. This NP self-assembly of hollow spheres may be viewed as a new route towards nanoparticle-based structures in which an unusual three-dimensional spatial ordering of the NP building blocks can be achieved. |
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Nanoscience and Nanotechnology
8:30 AM-11:45 AM, Tuesday, March 30, 2004 Marriott -- Grand Ballroom J, Oral
Division of Colloid and Surface Chemistry |