Fourier-transform infrared study of the adsorption of acetophenones on niobic acid

被引：7

作者：

Ahmad, I ^{[1
]}

Dines, TJ ^{[1
]}

Anderson, JA ^{[1
]}

Rochester, CH ^{[1
]}

机构：

[1] Univ Dundee, Dept Chem, Dundee DD1 4HN, Scotland

来源：

SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY | 1999年 / 55卷 / 02期

关键词：

niobia; surface acidity; acetophenone; adsorption;

D O I：

10.1016/S1386-1425(98)00200-5

中图分类号：

O433 [光谱学];

学科分类号：

0703 ; 070302 ;

摘要：

Infrared spectra are reported of acetophenone, acetophenone-methyl-d(3), and 4-methoxyacetophenone adsorbed on niobic acid which had been preheated at 393, 473 or 773 K. The dominant modes of immediate adsorption were ligation to Lewis acidic sites at low coverages and weak physical adsorption at high coverages. Strong hydrogen bonding also occurred but adsorbate protonation at Bronsted acidic sites was more difficult to recognise even for the more strongly basic methoxy compound. A slow surface condensation reaction occurred leading to H/D surface-adsorbate exchange for the CD3 compound and generating new surface hydroxy species. Ketones should only be used as indicators of surface acidity with extreme caution. (C) 1999 Elsevier Science B.V. All rights reserved.

引用

页码：397 / 409

页数：13

共 31 条

[1] IR study of nitrotoluene adsorption on oxide surfaces [J].