Lewis and Bronsted acidic sites in M4+-doped zeolites (M = Ti, Zr, Ge, Sn, Pb) as well as interactions with probe molecules: A DFT study
Yang, Gang1,3; Zhou, Lijun1; Han, Xiuwen2
刊名journal of molecular catalysis a-chemical
2012-11-01
卷号363页码:371-379
关键词Bronsted acidity Lewis acidity Density functional calculations Adsorption energy Probe molecules
英文摘要tetravalent-ion (m4+)-doped zeolites show excellent performances for a variety of catalytic processes, including the focusing biomass conversions. in this work, density functional calculations were performed to probe the lewis and bronsted acidities of various m4+-doped zeolites as well as to study interactions with probe molecules. the lewis and bronsted acidities increase in the orders of silicalite-1 << ge < ti < pb < sn < zr and silicalite-1 << ti < ge < zr approximate to b < pb < sn < al, respectively. the lewis acidities should be defined as the local sites around the m4+ ions, explaining why the adsorption energies give a more consistent order with lumo energies and absolute electronegativity rather than fukui functions. the formation of bronsted acidic sites is facilitated by doping with m4+ ions. albeit the bronsted acidities of these m4+-doped zeolites change greatly with sn being the strongest, their strengths are far below that of al3+. the interactions of five probe molecules of changing basicities with the bronsted acidic sites indicate that the formations of covalent and/or ionic structures are the proton-competing results: the covalent and ionic structures co-exist only for trimethyphosphine and pyridine of comparable basicity; otherwise, proton transfer will take place and result in only the ionic or covalent structures. the proton affinity fails to predict the bronsted acidity of zr and is evidenced, especially by formation of the covalent structure during pyridine adsorption. thus, this work presents a dynamic image of acid-base interactions and aids our understanding toward the catalysis of solid-state acids. (c) 2012 elsevier b.v. all rights reserved.
WOS标题词science & technology ; physical sciences
类目[WOS]chemistry, physical
研究领域[WOS]chemistry
关键词[WOS]density-functional theory ; effective core potentials ; fukui function indexes ; isomorphously substituted zsm-5 ; mcm-22 zeolite ; non-negativity ; mfi framework ; ts-1 zeolites ; active-sites ; beta-zeolite
收录类别SCI
语种英语
WOS记录号WOS:000309443400048
公开日期2015-11-17
内容类型期刊论文
源URL[http://159.226.238.44/handle/321008/143092]  
专题大连化学物理研究所_中国科学院大连化学物理研究所
作者单位1.NE Forestry Univ, Minist Educ, Engn Res Ctr Forest Biopreparat, Harbin 150040, Peoples R China
2.Chinese Acad Sci, Dalian Inst Chem Phys, State Key Lab Catalysis, Dalian 116023, Peoples R China
3.Eindhoven Univ Technol, Dept Chem Engn & Chem, NL-5600 MB Eindhoven, Netherlands
推荐引用方式
GB/T 7714
Yang, Gang,Zhou, Lijun,Han, Xiuwen. Lewis and Bronsted acidic sites in M4+-doped zeolites (M = Ti, Zr, Ge, Sn, Pb) as well as interactions with probe molecules: A DFT study[J]. journal of molecular catalysis a-chemical,2012,363:371-379.
APA Yang, Gang,Zhou, Lijun,&Han, Xiuwen.(2012).Lewis and Bronsted acidic sites in M4+-doped zeolites (M = Ti, Zr, Ge, Sn, Pb) as well as interactions with probe molecules: A DFT study.journal of molecular catalysis a-chemical,363,371-379.
MLA Yang, Gang,et al."Lewis and Bronsted acidic sites in M4+-doped zeolites (M = Ti, Zr, Ge, Sn, Pb) as well as interactions with probe molecules: A DFT study".journal of molecular catalysis a-chemical 363(2012):371-379.
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