(556g) Synthesis and Morphology Characterization of Mesoporous Silica/Single Wall Carbon Nanotubes Composites

Hu, Q. - Presenter, General Motors R&D Center
He, J. - Presenter, Tulane University
Lu, Y. - Presenter, Tulane University

Since the discovery of the mesoporous silica named MCM-41 in the early 1990s, the synthesis of mesoporous materials has became one of the main areas in materials chemistry because of the unique properties of mesoporous materials such as high surface areas, high pore volumes, uniform pore size distributions, controlled morphologies and pore structures which may lead to widely applications. In recent years, there has been a great interest in the synthesis of porous carbon-silica nanocomposites. Carbon nanotubes with excellent mechnical, chemical and electrical properties have attracted much interest to fabricate carbon nanotube based nanocomposites for the applications of sensors, supercapacitors and photocatalysts. In these report, the ordered mesoporous silica/single wall carbon nanotubes (SWNTs) nanocomposites with different morphology including fiber and rod like structure have been synthesized in different conditions and different SWNT loading. The highly ordered mesoporous silica/SWNTS rods were easily prepared at static reaction condition, while, fiber-like nanocomposites were formed at stirring reaction conditions. The addition of SWNTs into the self-assembly process has significant effect on the morphology and structure of obtained nanocomposites. The experiments show that SWNTs induce the nucleation and promote the precipitation of silica. At static condition, the length of the rod like nanocomposites decreased from 1.5 ìm (Without SWNTs) to 0.8 ìm (10% SWNTs) with the increased SWNT loading; at stirring condition, the morphologies of obtained nanocomposites changed from small particles (Without SWNTs) to more than 50 ìm fibers (10% SWNTs). The samples are characterized by nitrogen sorption isotherms, SEM, TEM, XRD and TGA.