Two-phase porous silica: Mesopores inside controlled pore glasses
Two-phase porous silica: Mesopores inside controlled pore glasses
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两相多孔二氧化硅：可控孔玻璃内的中孔
DOI：
10.1023/a:1017593411465
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发表时间：
2001
影响因子：
4.5
通讯作者：
W. Gille
中科院分区：
文献类型：
--
作者：
D. Enke;K. Otto;F. Janowski;W. Heyer;W. Schwieger;W. Gille
研究了由硅胶在大孔玻璃骨架原始孔内形成的介孔系统组成的“两相多孔二氧化硅”的结构和织构性质。采用77K氮气吸附、汞侵入、小角X射线散射(SAXS)、程序升温脱附(TPD)和27Al MAS核磁共振谱进行了表征。所研究的不同介孔玻璃的比表面积高达300m2/g，总孔容约为0.16 cm~3/g，孔径大小为~lt；2~10 nm，这取决于分相后的钠硼硅酸盐初始玻璃的酸浸条件。用碱性溶液去除介孔细分散硅胶相后，对大孔“框”玻璃的织构进行了表征。用Al(NO3)3溶液浸取分离相的初始玻璃，然后进行热处理，通过铝在二氧化硅骨架中的四面体配位，在所得到的介孔玻璃的表面形成Brnsted酸中心。
The structural and textural properties of “Two-Phase Porous Silica” consisting of a mesoporous pore system formed by finely dispersed silica-gel inside the original pores of a macroporous glass framework have been carefully investigated. Nitrogen adsorption at 77 K, Mercury Intrusion, Small Angle X-ray Scattering (SAXS), Temperature-Programmed Desorption (TPD) of ammonia and 27Al MAS NMR spectroscopy were used. Different mesoporous glasses investigated show BET surface areas up to 300 m2/g, a total pore volume of about 0.16 cm3/g and pore sizes of <2–10 nm, depending on the acid leaching conditions of the phase-separated sodium borosilicate initial glass. The texture of the macroporous “frame” glass was characterized after removing the mesoporous finely dispersed silica-gel phase with alkaline solution. Leaching of the phase-separated initial glass with Al(NO3)3 solution and followed by thermal treatment lead to the formation of Brönsted acid sites at the surface of the resulting mesoporous glasses by an incorporation of aluminium in tetrahedral coordination in the silica framework.