Charge-transfer doping

N.D. Lang, Ph. Avouris, Carbon-Atom Wires Charge-Transfer Doping, Voltage Drop, and the Effect of Distortions, Phys. Rev. Lett. 84 (2000) 358. 

The emeraldine salt, (II-7), can also be obtained directly from leucoemeraldine by charge transfer doping, with reactions analogous to (II-1) and (II-3). Thus, the doping of polyaniline has been described as two-dimensional in a space where one axis describes the charge transfer chemistry and the second, orthogonal axis describes the acid/base (protonation) chemistry [37]. 

Again, with respect to the last two points, surface oxidation might result in effective charge-transfer doping even at room temperature and thereby enhancing the density of free carriers and the effective mobility. 

Results of surface studies of subatomic layers of metals formed on polymer layers (discussed in Section IV.c.2.) have shown clear evidence for chemical interactions between metal and polymer, which range from charge transfer doping for alkali metals and calcium to covalent interactions for aluminum. In this case, the tunneling model is at odds. Research on the charge injection mechanism at the interface between polymer and metals must be continued. 

The optical and electronic properties of blends of soluble polythiophene derivatives and polystyrene (PSt) were investigated over the full range of compositions. The polyblend films, made conducting by charge transfer doping (reaction with NOPFe in acetonitrile) display an insulator-metal transition at the percolation threshold a volume fraction of 16% conducting polymer in PSt. 

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