ToF SIMS analysis

The depth distribution of light stabilisers in coatings has been studied in 1 - 3 mg microtomed slices, by means of SFE-GC with ToF-SIMS and nitrogen thermionic detection, as well as by direct ToF-SIMS analysis results were in good agreement [59]. As the SFE effluent... 

Figure 15.1 Collision cascade and secondary ion production during ToF SIMS analysis...

Synthetic polymers are very important in conservation science because they are commonly used for the conservation and restoration of artworks. Consequently, their chemical characterization must be precise enough to well define their innocuousness for art objects and their long term stability. An example is given in the ToF-SIMS analysis of polymers... 

As ToF-SIMS is a surface analytical technique, it is well suited to the study of surface interaction between a material and its environment or between a material and products applied to it. The surface modifications can then be studied, making it possible to establish links with degradation processes. Published papers on the study of natural fibres related to cultural heritage typically illustrate this aspect of ToF-SIMS analysis. 

The last example of ToF-SIMS analysis of natural fibres is of a structural characterization of wood species for an eventual dendrochronological study [Saito et al. 2008], The aim of this research was to develop a new method to differentiate heartwood and sapwood. In dendrochronology, when bark is not present on the samples, the presence of sapwood is the key to determining felling date. Usually, heartwood and sapwood can easily been differentiated by their colour, with heartwood being much darker. Nevertheless, in the case of... 

In an article published in Analytical Chemistry in 2004, Keune and Boon [2004a] present the application of ToF-SIMS analysis to a paint cross-section. The sample used was from the panel painting The Descent from the Cross (Museo del Prado, Madrid) by the early Flemish painter Rogier van der Weyden (1399/1400 1464). Scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX) and infrared microscopy were also used to complete and confirm the results. 

In addition to these numerous results, two other points are discussed by the authors fatty acid speciation and oil identification. These two aspects are developed in another publication written by the same authors [Keune et al. 2005]. The fatty acid speciation is based on the positive ion ToF-SIMS analysis and aims to prove if the fatty acids detected exist as free fatty acids, ester bound fatty acids or metal soaps. On account of the study of different standards, it is shown that when free fatty acids are present, the protonated molecular ion and its acylium ([M-OH]+) ion are detected. In cases of ester-bound fatty acid only the... 

The time-of-flight secondary ion mass spectroscopy (ToF-SIMS) analysis was performed on a CAMECA ION-TOF Model IV spectrometer. This instrument was equipped with a reflection-type ToF mass analyzer and a pulsed 25 kV primary... 

For the TOF SIMS analysis, only slides treated with a natural pH HAPS solution were used. These were subsequently extracted with warm and hot water. They were mounted into a grid sample holder for transportation into a VG IX23S time-of-flight (TOF) SIMS instrument operating at a vacuum of < 10 Torr with a microfocused liquid Ga metal ion primary beam source (30 keVx 1.0 nA). For charge compensation, an electron flood gun was used. The working resolution of the spectrometer was determined from a lead phthalocyanine spectrum for Pb+ at mlz = 208 and the molecular ion at mlz = 720, it was 500 and 1000, respectively. 

Fig. 20 Group selective labeling agents for chemical microscopy by TOF-SIMS. Analysis of a CCOA-labeled (right) and an FDAM-labeled beech sulfite pulp...

TABLE 1. Ions detected by TOF SIMS analysis of different nanostructured hybrid xerogels ... 

TABLE 7. Correlation between hydrophobicity data and TOF-SIMS analysis for xero-gels 40, 73 and 20... 

After chemical analysis with XPS at the various states of samples preparation, imaging ToF-SIMS analysis was applied to identify characteristic fragments of MAD-Gal at the surface. Figure 3 illustrates the negative F ion distribution on a masked-assisted patterned sample after photobonding. 

Stephan T., Jessberger E. K., Heiss C. H., and Rost R. (2003) TOF-SIMS analysis of polycyclic aromatic hydrocarbons in Alan HiUs 84001. Meteorit. Planet. Sci. 38, 109-116. 

Stapel, D. Benninghoven, A. Application of atomic and molecular primary ions for TOF-SIMS analysis of additive containing polymer surfaces. Appl. Surf. Sci. 2001,174 (3-4), 261-270. 

Although inorganic surfaces have been traditionally studied most by SIMS, presently the technique is also applied to polymeric substrates. For instance, Volooj et al. have studied the adsorption of cationic detergents on keratin fibers [486]. KeUer et al. reported the TOF-SIMS analysis of small molecules, such as peptides, Nile Blue and cholesterol, on surfaces using Nafion 117 as a matrix for controlled formation of molecular ions [487, 488]. This already points to new possibilities for ionization with SIMS for the analysis of larger fragments. To date, however, only masses up to 1760 MU (for insulin) have been reported [489]. 

In the previous section, we came to the conclusion that two catalytic sites were always obtained simultaneously, but not in the same proportions, when an Fe precursor and an N precursor were present at the same time in the pyrolysis reactor. This demonstration was performed with the help of ToF SIMS analysis of either heat-treated iron acetate or CIFeTMPP adsorbed on N-enriched prepyrolyzed PTCDA . The two catalytic sites were labeled Fe-N4/C and Fe-N2/C, according to the relative abundance of their typical ions detected by ToF SIMS. While Fe-N4/C corresponds to the catalytic site proposed by van Veen and illustrated in Figure 3.5, the full coordination of Fe-N2/C, illustrated in Figure 3.19, is not completely known. Possible Fe-N2+2/C catalytic structures have been proposed by various authors > but have not yet been confirmed. In the following discussion we will continue to use the Fe-N4/C and Fe-N2/C labels to identify these catalytic sites. 

Ota H., Akai T, Namita H., Yamaguchi S., Nomura M. XAFS and TOF-SIMS analysis of SEI layers on electrodes, J. Power Sources 2003, 119-121, 567-571. 

Probably the most important aspect of ToF-SIMS analysis involves the use of the technique to understand the variation in surface properties, such as... 

Lefevre M, Dodelet JP, Bertrand P (2005) Molecular oxygen reduction in PEM fuel cell conditions ToF-SIMS analysis of co-based electrocatalysts. J Phys Chem B 109 (35) 16718-16724... 

The characterization, distribution, conformation, and orientation of biomolecules feature the use of TOF-SIMS. TOF-SIMS analysis techniques have been applied to a certain extent to the surface and interface investigation of biosamples and biodevices such as biosensors and implant- materials. Typical examples are introduced in this section. 

The chemical mapping of simple ions such as C, Na, and have been applied to the TOF-SIMS analysis of biological samples of organs, tissues, and cells [22-27,89,90], and 3D images of the elemental distributions [91] have also been obtained. In addition, lateral and 3D distributions of Na+, K+, Ca+, and isotope-labeled elements in cells can be obtained with dynamic secondary ion mass spectrometry (DSIMS) imaging techniques [91,92]. 

Vanden Eynde, X., Bertrand, E. (1999) Quantification of polystyrene blend surfaces based on end group ToF-SIMS analysis. Appl Surf. Set, 141,1-20. 

KoUmer, E, Bourdos, N., Kamischke, R., Benninghoven, A. (2003) NonresonantLaser-SIMS and TOF-SIMS analysis of sub-[mu] m structures. Appl Surf Sci, 203-204, 238-243. 

De Witte, H., Conard, T., Vandervorst, W, Gijbels, R. (2003) Ion-bombardment artifact in TOF-SIMS analysis of Zr02/Si02/Si stacks. Applied Surface Science, 203-204, 523-526. 

Nygren, H., Eriksson, C., Hederstierna, K., Mahnberg, P. (2008) TOF-SIMS analysis of the interface between bone and titanium implants—effect of porosity and magnesium coating. Appl. Surf. ScL,255,1092-1095. 

Fletcher, J., Lockyer, N.R, Vickerman, J.C. (2006) C60, Buckminsterfullerene its impact on biological TOF-SIMS analysis. Surf Interface Anal, 38,1393-1400. 

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