TMNSPAREW’ !vlONCI.ITHIC METAL ION CONTAINING NANOPHASE AEROGELS
نویسندگان
چکیده
The formation of nlonolithie and transparent transition metal containing aerogel m~~ been achieved through co:,perative interactions of high molecular weight fictionalized carbohydrates and silica p .ecursors, which strong]y influence the kinetics of gelation. After initial gelation, subsequen: modification of the ligating character of the system, coordination of the group VIII metal ions, and supercritical extraction afford the aerogels. The structures at the nanophase Ievel have beer probed by photon and electron transmission and neutron scattering techniques to he!p elucida. e the basis for structural integrity together with the small entity sizes” that permit transparency i;! the visibIe range. They dso help with understanding the chemical reactivities of the metal-cl: ntaining sites in these very high surface area materials. These resuks are discussed in connectic: I with new reaction studies.
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