用于原位催化研究的紫外激光诱导表面荧光光谱仪

The surface study of catalyst and the other solid materials are focus field in Chemistry and Material in recent years. The laser technology, especially the Laser Raman Spectroscopy can give some important information such as surface structure , phase and the surface adsorption species，and many applications have been achieved in these fields. Ultra violet (UV) Laser Raman Spectroscopy have found many application in catalysis because it can avoid the fluorescence influence. On the other hands, UV Laser Induced Fluorescence Spectroscopy (UVLIFS) is also a very sensitive spectral technology, which can give the characteristic surface fluorescence about the surface state, structure, and surface species in the visible region. In this point of view, the UVLIFS is a new potential technology in the surface studies. .In this study, the UV laser induced surface fluorescence spectrometer applied for in-situ studies in catalysis has been made in our group. The spectrometer includes UV laser bought, the in-situ fluorescence cell which can be used in the catalytic reactions, an elliptical fluorescence collection systern which can be used in the UV-Infrared region, am image spectrometer with high light reflectivity, and the Charge Coupled Device (CCD) in the UV-visible region. All the parameters of the instrument have been tested and qualified the standard. .Some unsolved problems in the catalysis studies are tried using the UVLIF spetrometer. The Fluorescence spectra of some ordinary oxides and supports such as Al2O3, SiO2, MgO, ZrO2, TiO2, La2O3 , and ZnO under different temperatures and pressures were measured.The UVLIFS of differently modified and unmodified zeolites such NaA, NaY, USY, HZSM-5, and NH4ZSM-5 were also studied. The UVLIFS of ZnOon differently modified and unmodified zeolites such NaA, NaY, USY, HZSM-5, NH4ZSM-5 were also studied.We have exentively studied the ZnO/SiO2 catalysts using in situ LIFS technique. The results exhibited that the luminescence properties of the ZnO/SiO2 catalysts are indicative of the changes of the enviroment, state and structure of the luminescent species on the surface of catalyst.We also studied the preparation process of the ZnO/SiO2 catalysts with different Zn precursors using in situ LIFS technique. The spectra indicated that the two visible emission bands of ZnO are rised from different O defects.

紫外激光诱导的催化剂表面荧光光谱具有非常特征的荧光谱峰结构和很高的灵敏度，可获得催化剂表面组成、结构和微量物种变化的信息。本项目基于紫外激光诱导表面特征荧光光谱和已有紫外共振喇曼光谱的基础，自行设计紫外收集光系统和用于原位催化的光谱装置，研制紫外激光诱导表面荧光光谱仪，用于研究真实反应条件下的催化剂和催化过程。.