Spatially resolved surface chemistry

RIC 13] Richter B., Pauloehrl T., Kaschke J. et al, Three-Dimensional Microscaffolds Exhibiting Spatially Resolved Surface Chemistry , Advanced Materials, vol. 25, pp. 6117-6122, 2013. 

Spatially (Laterally) Resolved Surface Chemistry Analysis... 

Figure 9.5. Trapping of nucleophiles, here amines, with photogenerated thioaldehydes and selected examples of ToFSIMS images evidencing the successful spatially resolved surface grafting. The underpinning phenacyl sulfide ligation reaction can be found in Figure 9.1 b) (bottom reaction pathway). Reproduced with kind permission from the Royal Society of Chemistry from [PAU 13a]. For a color version of this figure, see WWW. iste. CO. uk/lalevee/dye.zip...

We can siunmarize at this point that the forces measured in AFM adherence force (and frequently friction) measurements depend crucially on the chemistry of the AFM tip and the surface of interest, as well as the medium in which the contact takes place. Hence by systematic variation of the tip chemistry via chemical modification/functionahzation and of the medium chemical contrast spatially resolved chemical imaging becomes possible. 

Spatially resolved functionalization via photoenol chemistry cannot only be applied on planar surfaces as described above, but also on cellulose and HA for the spatially controlled conjugation of S5mthetic polymers and peptides [BAL 77, DIS 09, SWA 70, TIS 13]. The general strategy is depicted in Figure 9.8. 

Films of InP on SiO are used as substrates for the fabrication of many semiconductor devices. Although there are in general no particular problems associated w ith the in-.service performance of the substrates, it is instructive to examine their surface chemistries, since during fabrication of devices both InP and SiO I lid their interfaces, become exposed. The various phases that appear are to be found distributed among a series of well-defined surface structures of various shapes and dimensions. Here it is clear that the material is laterally inhomogeneous. and if the local composition and chemistry are to be studied, then spatially resolved information, probably on the scale of a few pm. is necessary. 

Behm RJ. Spatially resolved chemistry on bimetallic surfaces. Acta Phys Pol A 1998 93 259-272. 

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