Polylayer Formation

The formation of polylayers on electrode surfaces is a rather rare 

According to the above scheme, first a monomer solute molecule is adsorbed on the electrode surface by replacing a solvent molecule (or cluster), next dimers normal to the adsorbing surface are formed by the  

The polylayer formation is such a complicated phenomenon that, at least as a first approximation, we may use Atj) = A( ) and m = 1. Then, substitution ofEqs. (13) and (14) into fijs. (39) results in the following equilibrium equations  

The treatment of the polylayer formation is significantly simplified if we assume that the short-range interactions have a negligible effect on the equilibrium properties. This yields /a I f and 

The equilibrium properties of a polylayer film can be determined from Eqs. (40) and (41), which allow for the calculation of the surface composition in terms ofA(j). Next the charge density may be calculated 

The formation of polylayers on electrode surfaces is a rather rare phenomenon and for this reason the corresponding publications are few. Our previous studies on the formation of polylayers have 

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The adsorbed layer is the scene of various interesting phenomena, like re-orientation of the adsorbate molecules, co-adsorption, polylayer formation, surface aggregation, adsorption of oligomers and, finally, surface phase transformations. All these phenomena can be treated within the frames of either the STE model or the models based on the LBS approach in precisely the same way We express the equilibrium equations first in terms of chemical potentials and next we introduce into these equations the expressions of the chemical potentials given by Eqs. (13) and (14). In some cases certain modifications are needed, as discussed below. 

For comparison, the inset of Figure 11 shows experimental C vs. E plots taken from It is seen that both plots exhibit the same basic features, i.e., a characteristic dip at positive polarizations and a plateau in the negative region. The lack of capacitance peaks in the experimental plots is likely due to the presence of the supporting electrolyte. A more thorough investigation of the polylayer formation is given in... 

In contrast to the scarcity of polylayer formation on electrodes, surface aggregation processes have been observed in many cases. hi order to model them we may adopt the single step process, rAj or... 

The process of oligo- and polymerisation can occur either on the surface of the wet silica or in the toluene solution. The formation of polylayered coatings was investigated in detail by Gorski et al.,91 reporting on the chemisorption of 3-methylacryloxypropyltrimethoxysilane from acetone solutions, containing various amounts of water. 

In saturated and supersaturated solutions one can observe deep capacitance depressions, which appear to correspond to the formation of polylayers rather than monolayers. The distinguishing feature here seems to be that no stationary capacitance can be reached [17]. 

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