Characterization of a poly(3-methyl thiophene) film by an in-situ dc resistance measurement technique and in-situ FTIR spectroelectrochemistry

UV–Vis spectroscopy as well as in situ FTIR spectroscopy of pyridine and CO adsorption were applied to determine the nature of Co species in microporous, mesoporous, and mixed oxide materials like Co–ZSM-5, Co/Na–ZSM-5, Co/Al–SBA-15, and Co/Al2O3–SiO2. Because all sample types show comparable UV–Vis spectra with a characteristic band triplet, the former described UV–Vis band deconvolution method for determination and quantification of individual cationic sites in the zeolite appears doubtful. This is also confirmed by results of pyridine and CO adsorption revealing that all Co–zeolite samples contain two types of Co2+ species located at exchange positions as well as in oxide-like clusters independent of the Co content, while in Co/Al–SBA-15 and Co/Al2O3–SiO2 only Co2+ species in oxide-like clusters occur. Consequently, the measured UV–Vis spectra represent not exclusively isolated Co2+ species, and the characteristic triplet band is not only related to γ-, β-, and α-type Co2+ sites in the zeolite but also to those dispersed on the surface of different oxide supports. The study demonstrates that for proper characterization of the formed Co species, the use of complementary methods is required.

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In situ FTIR-ATR spectroscopic investigations on the polymerization process and the redox behavior of poly( thienylpyrrole) thin film electrodes in aqueous and non-aqueous solutions. Part 1. Characterization of the polymerization process in acetonitrile containing different supporting salts

Journal of Electroanalytical Chemistry ◽

10.1016/s0022-0728(96)04723-7 ◽

1996 ◽

Vol 416 (1-2) ◽

pp. 157-166 ◽

Cited By ~ 4

Author(s):

Zhao Ping ◽

G.E. Nauer

Keyword(s):

Thin Film ◽

Aqueous Solutions ◽

Polymerization Process ◽

Redox Behavior ◽

In Situ Ftir ◽

Spectroscopic Investigations ◽

Thin Film Electrodes

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Effects of Chlorinated Polypropylene on the Conformation of Polypropylene in Polypropylene/Chlorinated Polypropylene/Polyaniline Composites

Journal of Spectroscopy ◽

10.1155/2015/317813 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Jianjun Chen ◽

Yueyue Jia ◽

Zhiye Zhang ◽

Xinlong Wang ◽

Lin Yang

Keyword(s):

Intensity Ratio ◽

Maximum Level ◽

In Situ Ftir ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Infrared Band ◽

X Ray ◽

Polyaniline Composites

We investigated the changes in the conformation and crystalline structure of polypropylene (PP) using a combination of Fourier transform infrared spectroscopy (FTIR), wide-angle X-ray diffraction (WAXD), and differential scanning calorimetry (DSC) based on PP/chlorinated PP (CPP)/polyaniline (PANI) composites. The DSC heating thermograms and WAXD patterns of the PP/CPP/PANI composites showed that theβ-crystal was affected greatly by the CPP content. Characterization of the specific regularity in the infrared band variation showed that the conformational orders of the helical sequences in PP exhibited major changes that depended on the CPP content. Initially, the intensity ratio ofA840/A810increased with the CPP concentration and reached its maximum level when the CPP content was <13.22% before decreasing as the CPP content increased further. The effect of increased temperature on the conformation of PP was studied by in situ FTIR. Initially, the intensity ratio ofA999/A973decreased slowly with increasing the temperature up to 105°C before decreasing sharply with further increases in temperature and then decreasing slowly again when the temperature was higher than 128°C.

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