Metal-to-Insulating Transition of Single Polyaniline (PANI) Nanowire: A Dedoping Effect

Abstract

We consider the metal-to-insulating transition on the electrical and optical characteristics of a single polyaniline (PANI) nanowire that was synthesized by nanochannel-assisted chemical oxidative polymerization. After treatment with a solution at pH 2, the conductivity of the PANI nanowire decreased to ∼0.95 S/cm, which was ∼1.3 times lower than that of an as-synthesized PANI nanowire at room temperature. We examined this dedoping effect (M-I transition) by studying low-temperature current−voltage characteristics and micro-Raman spectroscopy characteristics.