INOR 496 |
| Uniform gold nanorods well distributed in SBA-15 matrix were synthesized by performing a seed-mediated growth process in the channels of SBA-15 which functions as a hard-template to confine the diameter of gold nanorods. By simply changing the amount of gold precursor, gold nanorods prepared by this method posses a fixed diameter (6-7 nm) and tunable aspect ratios from 3 to 30. Both TEM and diffuse reflective UV spectra confirmed the formation of gold nanorods and their relatively narrow size distribution. To reveal the geometrical distribution of gold nanorods in SBA-15 matrix, E-tomography technology was utilized and a uniform 3-dimensional distribution of gold nanorods in the SBA-15 channels of different layers was found. After removing the host matrix, uniform unsupported gold nanorods were obtained. No significant decrease in surface area or pore size of composite was found in N2-absorption results, which indicates the growth of the nanorods did not block the open mesoporous structure of SBA-15. Our interest in this method lies not only in fabricating length tunable ultrafine gold nanorods but also in their potential application as catalysts. The gold nanorods/SBA-15 composite, with an open porous structure and catalyst center (gold nanorods) in tunable length but the same diameter, is a promising model to study shape-dependent catalytic activity. |
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Nanoscience - Characterization and Applications
9:00 AM-1:00 PM, Tuesday, April 8, 2008 Morial Convention Center -- Rm. 219, Oral
Division of Inorganic Chemistry |