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Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: IDiscoid Bicelles as Efficient Templates for Pillared Lamellar Periodic Mesoporous Silicas at pH 7 and Ultrafast Reaction Times | Mohanty et al. Nanoscale Res Lett 2011 6 61 http www.nanoscalereslett.eom content 6 1 61 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Discoid Bicelles as Efficient Templates for Pillared Lamellar Periodic Mesoporous Silicas at pH 7 and Ultrafast Reaction Times Paritosh Mohanty Jinwoo Lee Kerney Jebrell Glover Kai Landskron Abstract We report the first synthesis of periodic mesoporous silicas templated by bicelles. The obtained materials form novel pillared lamellar structures with a high degree of periodic order narrow pore size distributions and exceptionally high surface areas. Hardly any other field of materials chemistry has experienced as much growth over the last 20 years as the field of periodic mesoporous materials 1 . Numerous applications have been found for periodic mesoporous materials in catalysis 2 separation 3 chemical storage 4 and delivery 5 . Periodic meosporous materials can be produced by either soft-templating 6 or hard-templating 4 methods. Soft-templating is the dominating technique because hard-templating requires additional undesirable reaction steps. With only one exception 7 all soft-templated periodic mesoporous materials are produced by templation of micelles. Most micellar templates are produced from cationic 6 or non-ionic 8 surfactants. Typical cationic surfactants are quaternized ammonium salts for example cetyltrimethyl ammonium bromide CTAB . Amphiphilic block-copolymers such as block-copolyethers have been extensively used as non-ionic surfactants. More recently micelles from anionic surfactants have been used as templates in the presence of co-structure directing agents 9 . The use of new micellar templates has substantially driven the field of periodic mesoporous materials because new templates have frequently led to the discovery of new mesostructures with new pore systems 9 . With the exception of folic acid 7 no other templates but surfactant-containing micelles are known today for the .
