Semiconductors ferrocene polymers

Third, metallocene units, such as ferrocene or ruthenocene, have been linked to phosphazene cyclic trimers or tetramers and these were polymerized and substituted to give polymers of the type mentioned previously (41). Polyphosphazenes with ferrocenyl groups can be doped with iodine to form weak semiconductors. Polymer chains that bear both ruthenocenyl and ferrocenyl side groups are prospective electrode mediator systems. 

The same type of methodology was also used to prepare ferrocene-containing arylidene polyesters 122 in good yields from dicarboxyl ferrocenes and organic diols. These materials were characterized by elemental analysis, IR spectroscopy, viscometry, and WAXS. The polymers were found to be semicrystalline but were soluble in polar organic solvents. Conductivity studies showed an n-type semiconductor behavior (cr = 3 x 10 Scm at room temperature) that followed a one-term Arrhenius-type equation with increasing conductivity over the range 25-220 °G. 

Ferrocenes that are separated by other type of spacer units such as CH=CH groups, [poly(ferrocenylenevinylene)s] (M s of 3,000-10,000 MJM - 2.2-2.S) have been prepared by a Zn/TiCU-catalyzed condensation reaction of l,r-ferrocenyl dialdehydes (Fig. 8.8) [3]. Analogous to poly(vinylferrocene)s, these polymers are also insulators however, they can be converted to semiconductors upon doping [29]. 

In many classical thermoelectrochemical experiments in open cells, which are directed at modem substances or actual processes, transport properties were of interest [89-93]. In a comprehensive impedance study of a conducting polymer, poly(tetracyanoquinodimethane) (polyTCMQ), Inzelt determined fundamental constants like diffusion coefficient, double-layer capacity and other quantities of the semiconductor layer as a function of temperature [89], Reduction kinetics of buckminsterfullerene Ceo has been studied [90] diffusion coefficients of different systems have been determined [91-93], among them/) of ferrocene/ferricinium in acetonitrile [92] and of vanadium ions [93]. In the latter example, activation energy of diffusion was also of interest. 

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