Electrochemical polymerization of phenanthrene in mixed electrolytes of boron trifluoride diethyl etherate and concentrated sulfuric acid

摘要

A novel high-quality polyphenanthrene(PPH)film with electrical conductivity of 10~(-1)S cm~(-1)was synthesized electrochemically by direct anodic oxidation of phenanthrene in boron trifluoride diethyl etherate containing 10% concentrated sulfuric acid(v/v).The oxidation onset potential of phenanthrene in this medium was measured to be only 0.91 V versus saturated calomel electrode(SCE),which was lower than that determined in acetonitrile +0.1 mol L~(-1)Bu4NBF4(1.56 V versus SCE).As-formed PPH films from this medium showed good electrochemical behavior and stability.De-doped PPH films were thoroughly soluble in dimethylsulfoxide or CHCl3.The structure and morphology of the polymer were investigated using UV-visible and Fourier transform infrared(FTIR)spectroscopy and scanning electron microscopy.FTIR and ~1H NMR spectra showed that the PPH was grown via the coupling of the monomer mainly at the C_4,C_5,C_9 and C_(10)positions.Fluorescence spectral studies indicated that PPH was a blue-green light emitter.