Ultrathin film modification

The book is directed to advanced students and scientists working in the fields of electrochemistry, phase formation and crystal growth, surface chemistry and physics, ultrathin film formation, and structuring and modification of solid state surfaces. 

The investigation on the electrochemical epitaxial growth of palladium on gold and platinum singlemonolayer coverage of palladium on Pt(lll) electrode by the immersion technique for the first time [74]. Llorca and coworkers investigated the irreversibly adsorbed palladium on Pt(hiJ) in acidic solution [75] and reported that electrocatalytic activity for the oxidation of formic acid on the Pt(lOO) electrodes vras improved drastically by the palladium-adlayer modification, while that on the Pt(lll) electrode was not greatly affected by the Pd-modification [76]. However, it is difficult to prepare an ultrathin film of palladium with various thickness by the immersion technique, and STM observation of the atomic structure of these surfaces is not available yet. 

In this section, the reader will first be introduced to the general properties of polaritons at the interface of two media and within a layer. Then, following Vinogradov [26] and Ruppin [23], the results of a quasi-static treatment will be discussed to gain insight into the physical nature of the absorption bands observed in the IR spectra of ultrathin films. For further detailed discussion of both the theoretical and experimental aspects of the polariton theory and its approximations, several reviews [12-14] and monographs [15, 16, 24] are recommended. Modifications of polaritons in superlattices are considered in Refs. [27-29]. 

To simplify routine analysis of bulk samples, the ATR accessories of the new generation have optimized optical configurations with predetermined angles of incidence. These accessories, however, are less effective for studying ultrathin films as compared to the older modifications, which allow one to optimize the angle of incidence for a given system. A more detailed information on different ATR accessories is presented, for example, in Refs. [25, 27, 30],... 

Sun, F., et al. Polymer ultrathin films by self-assembly bound perfluorinated monolayers and their modification using in situ derivatization strategies. Thin Solid Films 242(1-2), 106-111 (1994)... 

It is well known that the surface/interface of materials usually exhibits properties and behaviors that are considerably different from the bulk phase. The functionality of the soKd surface modified by an organic thin film, such as a self-assembled monolayer (SAM), Langmuir-Blodgett (LB) ultrathin film or polymer thin film, depends significantly on its surface molecular structure [1-4]. Therefore, elucidation and control of the surface molecular structure is essential to understand the novel functionality introduced by the modification. Most existing surface techniques require the sample to be placed in an ultrahigh vacuum (UHV) environment [5] and are therefore unsuitable for studies in either air or liquid. On the other hand, as comprehensively reviewed in this chapter, a number of modem instrumental analysis methods, such as infrared reflection absorption... 

Key words Self assembly - surface modification - ultrathin films -polymers... 

The cathode photocurrent is in proportion to the number of TCPP layers at least up to 10 cycles. The efficiency is greatly dependent on the kinds of oxide gel. These experimental observations suggest that electron transfer from the electrode to the porphyrin via the oxide gel layer is an essential mechanism of the photocurrent generation. Oxygen molecules as an electron acceptor readily diffuse in the oxide gel films of about 20 nm thickness. The electron transfer from the electrode to the porphyrin is assisted by satisfactory conductivity of the gel layer. The overall photocurrent value is considerably smaller than the conventional wet solar cell [11]. However, modification of the electrode surface by ultrathin oxide gel films will facilitate the design of novel light harvesting devices. 

J.N. D Amour, C.W. Frank, and U. Okoroanyanwu, Measuring thermophysical properties of ultra thin photoresist films, Proc. SPIE 4690,936 942, 2002 Modifications to thermophysical behavior in ultrathin polymer films, Proc. SPIE 5039, 996 1007 (2003). 

Ultrathin polymer films (in the extreme case, only one monomolecular layer thick as a SAM) are of special interest from an applied point of view for all kinds of surface modifications — lubrication, isolation, adhesion, or any possible purpose. Langmuir monolayers are also ultrathin layers which can be assembled in multilayer supramolecular structures by means of the LBK technique. 

Bhushan B, Hansford D, Lee KK (2006) Surface modification of silicon and polydimethylsiloxane surfaces with vapor-phase-deposited ultrathin fluorosilane films for biomedical nanodevices. J Vac Sci Technol A 24(4) 1197-1202... 

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