کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
76129 49132 2008 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The radial dependence of the spatial mesostructure of monodisperse mesoporous silica spheres
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
The radial dependence of the spatial mesostructure of monodisperse mesoporous silica spheres
چکیده انگلیسی

The pore structure of monodisperse mesostructured silica spheres has been investigated by a combination of X-ray diffraction, nitrogen sorption isotherms and transmission electron microscopy (TEM). The radial dependence of the mesostructure has been obtained by TEM analysis of thin microtomed slices taken at different distance from the particle core. A structural model is proposed based on the TEM observations where bundles of the hexagonally ordered cylindrical channels bend and twist, without any preferred direction, close to the particle core and attain a radially extended structure closer to the particle surface. Thermal calcination results in a pore shrinkage of about 16% and some loss of the long-range mesostructure while radiative disintegration and partial removal of the organic template by an UV/Ozone treatment had a negligible effect on the inorganic framework in terms of pore size or spatial pore arrangement.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Microporous and Mesoporous Materials - Volume 112, Issues 1–3, 1 July 2008, Pages 589–596
نویسندگان
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