NMR and FTIR characterization of surface acidity of fluorinated gamma-Al2O3
文献类型：期刊论文
| 作者 | Liu, CK; Yie, ZH |
| 刊名 | CHEMICAL JOURNAL OF CHINESE UNIVERSITIES-CHINESE
 |
| 出版日期 | 2002-10-01 |
| 卷号 | 23期号:10页码:1952-1955 |
| 关键词 | fluorinated gamma-Al2O3 surface acidity adsorption solid NMR in situ FTIR |
| 英文摘要 | The effect of fluorination on the surface acidity of gamma-Al2O3 and the influence of the amount of. fluorine on the types strength and number of acid sites have been studied. IR spectra of pyridine(PY) and 2,6-dimethylpyridine(DMPY) adsorbed-desorbed on fluorinated gamma-Al2O3(F/gamma-Al2O3) and P-31 MAS NMR of trimethylphosphine (TMP) adsorbed on F/gamma-Al2O3 have been used to measure the acidities of F/gamma-Al2O3,. It has been found that F/gamma-Al2O3 presents both Bronsted and Lewis sites. IR spectra of pyridine adsorbed on F/gamma-Al2O3 pretreated in vacuum at 300 K show four bands at 1 451, 1 491, 1 580 and 1 617 cm(-1), the bands are assigned to PY adsorbed on Lewis acid sites, and two bands at 1 544 and 1 640 cm(-1) are assigned to PY adsorbed on Bronsted acid sites. IR spectra of 2,6-dimethylpyridine adsorbed on F/gamma-Al2O3 pretreated in vacuum at 300 K shows a major band at. 1 637 cm(-1) due to DMPY adsorbed on Bronsted acid sites. P-31 MAS NMR spectra of trimethylphosphine adsorbed on F/gamma-Al2O3 pretreated in vacuum at 353 K show three peaks at delta - 56.5, - 28.2 and -21.9 are assigned to TMP chemisorption to different types of Lewis sites, and a peak at delta - 2.8 is assigned to TMP chemisorption to Bronsted acid site. When the fluorine content increases, the total number of Lewis acid sites decreases, wheriaas their strength increases, a few of new types of Lewis acid sites are created simultaneously. The number and strength of Bronsted acid site presents a maximum for samples with 2%-3% of fluorine content. TMP as a sensitive NMR probe molecule is introduced for acidity measurements on F/gamma-Al2O3 surfaces in the present study. P-31 MAS NMR results agree with that of IR. |
| WOS标题词 | Science & Technology ; Physical Sciences |
| 类目[WOS] | Chemistry, Multidisciplinary |
| 研究领域[WOS] | Chemistry |
| 关键词[WOS] | SOLID-STATE NMR ; SITES |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000178758400029 |
| 公开日期 | 2015-12-08 |
| 源URL | [http://ir.wipm.ac.cn/handle/112942/8717]  |
| 专题 | 武汉物理与数学研究所_2011年以前论文发表（包括2011年） |
| 作者单位 | 1.Zhongshan Coll, Dept Appl Chem, Zhongshan 528402, Peoples R China 2.Chinese Acad Sci, Wuhan Inst Phys & Math, State Key Lab Magnet Resonance & Atom Mol Phys, Wuhan 430072, Peoples R China |
| 推荐引用方式 GB/T 7714 | Liu, CK,Yie, ZH. NMR and FTIR characterization of surface acidity of fluorinated gamma-Al2O3[J]. CHEMICAL JOURNAL OF CHINESE UNIVERSITIES-CHINESE,2002,23(10):1952-1955. |
| APA | Liu, CK,&Yie, ZH.(2002).NMR and FTIR characterization of surface acidity of fluorinated gamma-Al2O3.CHEMICAL JOURNAL OF CHINESE UNIVERSITIES-CHINESE,23(10),1952-1955. |
| MLA | Liu, CK,et al."NMR and FTIR characterization of surface acidity of fluorinated gamma-Al2O3".CHEMICAL JOURNAL OF CHINESE UNIVERSITIES-CHINESE 23.10(2002):1952-1955. |
入库方式： OAI收割
来源：武汉物理与数学研究所
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