CHEMICAL DOPING OF POLYACENIC SEMICONDUCTIVE MATERIAL WITH VARIOUS LEWIS-ACIDS OF BULKY SIZE

It is demonstrated that porous polyacenic semiconductive (PAS) materia ls prepared by pyrolysis of phenol-formaldehyde resin can be doped wit h transition metal halides (FeCl3, NbCl5, MoCl5, TaCl5 and WCl6), caus ing a maximum increase in electrical conductivity of five orders of ma gnitude. The elemental analyses of the porous PAS samples doped with t ransition metal halides indicate that the electrical conductivities ha ve a nonlinear relationship with the metal concentration as has been r eported in polyacetylene. Furthermore, change of the coinductivity of the AsF5-doped PAS material is discussed in connection with decomposit ion of the dopant.