In situ diffuse reflectance infrared spectroscopy study of CO adsorption on SnO2
In situ diffuse reflectance infrared spectroscopy study of CO adsorption on SnO2
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DOI：
10.1016/s0040-6090(01)00979-8
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发表时间：
2001-07-16
期刊：
影响因子：
2.1
通讯作者：
Hoffmann, V
中科院分区：
文献类型：
--
作者：
Emiroglu, S;Bârsan, N;Hoffmann, V
采用室温漫反射红外傅里叶变换（DRIFT）光谱法研究了不同制备的二氧化锡样品与CO的表面相互作用。作为样品，使用商业粉末（Merck）和通过溶胶-凝胶制备获得的自制粉末。结果表明，样品中存在多条与OH基团、配位水和凝聚水相对应的谱带，这些谱带的形态和强度与样品来源和储存条件有关。此外，所有样品的光谱显示对应于不同的水合质子（H3 O+，H5 O2+）和不同强度的碳酸根离子的频带。为了获得有关SnO 2粉末和CO之间的相互作用的信息，进行了原位测量。我们发现，不同的束缚水和特定的表面OH-基团与CO反应，表面碳酸根离子解离，因为酸性中间产物。结果，对应于物理吸附的CO的不同谱带出现在约2200 cm（-1）处，以及对应于共价结合的螯合和桥接双齿碳酸盐和羧酸盐的区域中的变化（在1700和1000 cm（-1）之间）。(C)2001 Elsevier Science B. V.保留所有权利。
The surface interaction between differently prepared tin oxide samples and CO was studied by Diffuse Reflectance Infrared Fourier Transform (DRIFT)-spectroscopy at room temperature. As samples, commercial powders (Merck) and home-made powders obtained by a sol-gel preparation were used. Several bands corresponding to isolated and rooted OH groups, coordinated water and condensed water in two forms: ordered lavers of water molecules and water in the liquid form, were found. Their appearance and intensity depended on the sample origin and storing conditions. Moreover, the spectra of all samples show bands corresponding to different hydrated protons (H3O+, H5O2+) and carbonate ions of different intensities. To get information about the interaction between SnO2 powders and CO, in-situ measurements were conducted. We found that differently bound water and specific surface OH-groups react with CO and that surface carbonate ions dissociate because of acidic intermediate products. As a result, different bands corresponding to physisorbed CO appear at approximately 2200 cm(-1), together with changes in the region corresponding to covalent bound chelating and bridging bidentate carbonates and carboxylate (between 1700 and 1000 cm(-1)). (C) 2001 Elsevier Science B.V. All rights reserved.