Solid-State MAS NMR Studies of Br酶nsted Acid Sites in Zeolite H-Mordenite

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• 作者：Hua Huo ; Luming Peng ; Zhehong Gan ; Clare P. Grey
• 刊名：The Journal of the American Chemical Society
• 出版年：2012
• 出版时间：June 13, 2012
• 年：2012
• 卷：134
• 期：23
• 页码：9708-9720
• 全文大小：684K
• 年卷期：v.134,no.23(June 13, 2012)
• ISSN：1520-5126

文摘

¹⁷O鈥?sup>1H double resonance NMR spectroscopy was used to study the local structure of zeolite H-Mordenite. Different contact times were used in cross-polarization magic angle spinning (CPMAS) NMR, CP rotational-echo double resonance (CP-REDOR) NMR, and heteronuclear correlation (HETCOR) NMR spectroscopy to distinguish between Br酶nsted acid sites with different O鈥揌 distances. The accessibility of the various Br酶nsted acid sites was quantified by adsorbing the basic probe molecule trimethylphosphine in known amounts. On the basis of these experiments, locations of different Br酶nsted acid sites in H-Mordenite (H-MOR) were proposed. The use of ¹⁷O chemical shift correlations to help assign sites is discussed.