Fourier-transform laser Raman spectroscopy of adsorbed pyridine and nature of acid sites on calcined phosphate/Zr(OH)4

The ethylenediamine trimolybdate (ENTMo) can show unusually photochromic and thermochromic properties and there exists in the difference of chromic mechanisms, which has been proved in our previous work [1]. In this paper, X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) and laser Raman spectroscopy (LRS) of the colored samples are characterized and analyzed in detail. The crystal structure, the inorganic skeleton and the microenvironment of center ions of the colored samples do not substantively change except distortion. The color difference of the photochromic and the thermochromic samples is discussed and that the difference of reduction sites result in their different chromic mechanisms is suggested.

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Applications of Fourier Transform Raman Spectroscopy in an Industrial Laboratory

Applied Spectroscopy ◽

10.1366/0003702894202913 ◽

1989 ◽

Vol 43 (3) ◽

pp. 516-522 ◽

Cited By ~ 37

Author(s):

F. J. Bergin ◽

H. F. Shurvell

Keyword(s):

Raman Spectroscopy ◽

Fourier Transform ◽

Near Infrared ◽

Laser Raman Spectroscopy ◽

Analytical Technique ◽

Laser Raman ◽

Fourier Transform Raman Spectroscopy ◽

Ft Raman Spectroscopy ◽

Ft Ir ◽

Fourier Transform Raman

In the past, the usefulness of laser Raman spectroscopy as an analytical technique in industrial laboratories has been greatly reduced by problems of laser-induced fluorescence. One method of circumventing this problem is to use near-infrared excitation coupled with a modified FT-IR spectrometer. In this paper, we report the results of some initial exploratory experiments which indicate that significant fluorescence rejection can be achieved. This fluorescence rejection opens up new areas of application for Raman spectroscopy. The advantages and limitations of FT-Raman spectroscopy are discussed. In addition, some initial experiments are outlined on Fourier transform Raman microscopy using a conventional microscope.

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Controlled-Atmosphere Rotating Cell for in Situ Studies of Catalysts Using Laser Raman Spectroscopy

Applied Spectroscopy ◽

10.1366/0003702804730727 ◽

1980 ◽

Vol 34 (2) ◽

pp. 146-150 ◽

Cited By ~ 25

Author(s):

C. P. Cheng ◽

J. D. Ludowise ◽

G. L. Schrader

Keyword(s):

Raman Spectroscopy ◽

Molybdenum Trioxide ◽

Laser Raman Spectroscopy ◽

Controlled Atmosphere ◽

Pyridine Adsorption ◽

Laser Raman ◽

Considerable Portion ◽

Adsorbed Pyridine ◽

New Form

Laser Raman spectroscopy was used to characterize molybdenum on alumina catalysts using a controlled-atmosphere rotating cell. In situ spectra could be recorded at temperatures up to 600°C and pressures as low as 1.333 × 10−4 Pa. Catalysts were examined during the drying and calcining operations; adsorption of pyridine was also studied. Spectra of the dried and calcined catalysts indicated the presence of aggregated molybdenum species. Close resemblance to the aggregation of molybdenum species in aqueous solution was apparent. At higher loadings of molybdenum, a molybdenum trioxide phase developed. Adsorbed pyridine spectra indicated that a considerable portion of the alumina surface was not covered by molybdenum even after molybdenum trioxide was formed. A new form of pyridine adsorption associated with the aggregated phase was observed.

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