Self-assembled rigid conjugated polymer nanojunction and its nonlinear current–voltage characteristics at room temperature

Abstract

A gold/polymer/gold nanojunction was fabricated by the self-assembly of a rigid polymer, namely poly(p-phenyleneethynylene)s with thioacetyl groups, between gold nanogap electrodes. The self-assembly depends on: (i) the ideal rigidity of the polymer molecules and (ii) the strong affinity of the thioacetyl/thiol end groups of the polymer for the Au surface. The current–voltage (I–V) characteristics of the conjugated polymer nanojunction exhibited stepwise features (some steps appeared as peaks) at room temperature. The I–V can be explained as electron tunneling through the nanojunction.