Diffuse reflectance Fourier transform infrared substrate studies

SAMs of allgrlphosphonic acids (butylphosphonic acid, octylphosphonic acid, undecylphosphonic acid and octadecylphosphonic acid) on native niekel oxide allow substrates to be functionalized easily. Monolayer formation has been investigated by diffuse reflectance Fourier transform infrared spectroscopy, non-contact mode atomic force microscopy, contact angle measurements and matrix-assisted laser desorption ionization mass spectrometry. Cyclic voltammetry and electrochemical impedance spectroscopy studies showed that the monolayer increased surface resistance to oxidation. [Pg.291]

Abstract—This study extends previous work on silanized kaolin clays to other substrates, such as aluminum hydroxide. It will also show that high precision quantitative Fourier Transform Infrared Spectroscopy (FT-IR) diffuse reflectance measurements can be performed on this vinyl silanized substrate and predict that other silanized finely divided powders can be analyzed using these techniques. [Pg.289]

Also, Fourier transform infrared absorption spectroscopy provides relevant information regarding the specific interactions of different probes within substrates [17], especially in the diffuse-reflectance mode when applied to the study of powdered opaque surfaces that disperse the incident radiation. The extension of this technique to obtain time resolved transient absorption spectra in the IR wavelength range (laser flash-photolysis with IR detection) will certainly play in the near future an important role in terms of clarifying different reaction mechanisms in the surface photochemistry field [17c, 18]. [Pg.279]

Variable-temperature diffuse reflectance infrared Fourier transform spectroscopy was used in conjunction with pyridine desorption studies to assess the acidity of a siliceous surface. An amorphous, porous silica substrate was investigated. The results contribute to an understanding of the acidic strength and the distribution of acidic sites on this material. A hydrogen-bonding interaction was observed between pyridine and the surface. Isothermal rate constants and an activation energy for the desorption process are reported and can be used as direct measures of surface site acidity. [Pg.254]