Vibrational spectroscopy morphology

Schlapka A, Kasberger U, Menzel D, Jakob P. 2002. Vibrational spectroscopy of CO used as a local probe to study the surface morphology of Pt on Ru(0001) in the submonolayer regime. Surf Sci 502/503 129. 

In this review, the relationships between structure, morphology, and surface reactivity of microcrystals of oxides and halides are assessed. The investigated systems we discuss include alkali halides, alkaline earth oxides, NiO, CoO, NiO-MgO, CoO-MgO solid solutions, ZnO, spinels, cuprous oxide, chromia, ferric oxide, alumina, lanthana, perovskites, anatase, rutile, and chromia/silica. A combination of high-resolution transmission electron microscopy with vibrational spectroscopy of adsorbed probes and of reaction intermediates and calorimetric methods was used to characterize the surface properties. A few examples of reactions catalyzed by oxides are also reported. 2001... 

The purpose of this chapter is to demonstrate the usefulness of vibrational spectroscopy [1-8] and atomic force microscopy (AFM) [9,10] in the studies of monolayers on air/solid interfaces. In this chapter, considerable attention is paid to the combined use of vibrational spectroscopy and AFM. These two techniques, widely used in the studies of monolayers on air/solid interfaces, have complementary advantages vibrational spectroscopy is suitable to investigate structure and orientation of monolayers [2,3,6-9], while AFM is useful to observe the surface morphology and the thickness of the monolayers [9]. 

IR spectroscopy is largely used for the characterization of metal oxide catalysts in relation to their structural features, with additional possible information on their morphology. Several collections of IR, Raman or both IR and Raman spectra of inorganic materials and minerals have been published, and are available electronically. In the following we will briefly review some of the applications of vibrational spectroscopies in the characterization of such materials. 

The reactivity of oxide supported metals has received considerable attention because of the importance of such systems in heterogeneous catalysis. The morphology (structure and size) of the supported particle and its stability, the interaction of the particle with the support, and the crossover of adsorbed reactants, products and intermediates between the metal and oxide phases are all important in determining the overall activity and selectivity of the system. Because of the relative insensitivity of an optical technique such as IR to pressure above the catalysts, and the flexibility of transmission and diffuse reflection measurement techniques, vibrational spectroscopy has provides a considerable amount of information on high area (powder) oxide supported metal surfaces. Particularly remarkable was the pioneering work of Eichens and Pliskin [84] in which adsorbed CO was characterised by IR spectroscopy on... 

Vibrational spectroscopy is one of the most widely used techniques for the morphological characterisation of high gas and aroma barrier materials used in food packaging. However, because of the highly hydrophobic character of ethylene-vinyl alcohol (EVOH) resins, it is usually LDPE, a high water barrier material that is put in direct contact with the packaged commodity, i.e., multi-layer EVOH-LDPE film [46]. 

Vibrational spectroscopy makes it possible to assess morphological parameters (e.g. order and orientation) of the blend constituents separately. This has, for instance, been demonstrated with PP/polyamide melt spun fibers. The composition and morphology of microdomains in PP... 

Analysis of Structural Unit-SiZG. The strength of vibrational spectroscopy lies in its ability to characterize chemical composition and localized structure of polymers. The observation of the intense longitudinal acoustic mode (LAM) in the extremely low frequency region (<50 cm ) of the Raman spectra of semicrystalline polymers provides a very different morphological tool for measurement of structural subunits in the order of several hundreds of angstroms. 

A series of copolymers of D,L-lactide and CL were synthesized by ROP using zinc lactate as a catalyst and carrying out the reaction at 145""C for 8 days. The characterization of PCL and its copolymers with lactides is often done by size exclusion chromatography, DSC, NMR, and stress-strain analysis. Kister et al. used vibrational spectroscopy, particularly Raman spectroscopy, for determination of morphology, conformation, configuration, and composition of the copolymers [49]. Raman spectroscopy thus appeared to be a suitable method for the identification of P(DLA-co-CL) samples directly from solid samples without any special preparation. 

Characterisation of molecular orientation is important since many physical and mechanical properties of polymers depend upon the extent and uniformity of that orientation. Orientation can be measured by using a variety of techniques [260,261]. Vibrational spectroscopy is particularly attractive since it is widely applicable, it often allows characterisation of amorphous and crystalline phases separately, it simultaneously provides morphological data (section 4.9), and it can be used to map orientation with high spatial resolution. 

Vibrational spectroscopy techniques will continue to be key tools in polymer characterisation and structure elucidation. The general applicability of FTIR techniques to all morphological and processed forms has been enhanced by the arrival of the simply operated FT-Raman systems, which supplement a wide range of established and complementary uses of Raman spectroscopy. 

Going along with high morphological diversity (cell size ranges from single micrometer up to several hundred micrometers) and environmental situations in the natural habitat, the experimental setup for algae analysis by vibrational spectroscopy has to be adapted to the scientific point of interest in... 

It should be borne in mind that the cooling or stretching of certain elastomers can lead to crystallisation. Hence, the morphology of such samples can be studied using vibrational spectroscopy. 

Chen C, Wang J, Woodcock SE, Chen Z. Surface morphology and molecular chemical structure of poly(n-butyl methacrylate)/polystyrene blend studied by atomic force microscopy (AFM) and sum frequency generation (SFG) vibrational spectroscopy. Langmuir 2002 18 1302-9. 

Figure 11.3 ATR-FTIR analysis of commercial silicone elastomeric foam (Dow Corning RTV 5370). Although the overall chemical functionalities of the silicone are observable using vibrational spectroscopy, they provide only broad average of the materials structure and provide little information on the network structure and morphology.

Fourier Transform (FT) Ranun spectroscopy (Model RFS 100/S, BRUKER Co.) using ND YAG laser was used to analyze the products on their structure electronic and vibration properties. The morphology of CNTs was observed by scanning dartron microscopy (SEM, Model S-4200, Hitach Co.) and transmission electron microscope (TEM, Modd JEOL 2000FX-ASID/EDS, Philips Co.). 

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