High electrical conductivity in directionally polymerized C60 nanowires by grazing incidence of single particles†

Abstract

As organic electronics continue to evolve, there is a growing demand for nanometer-scale microfabrication techniques for organic semiconductors. Although precise 2D alignment and 3D integration are essential for future device applications, significant challenges remain, particularly with organic materials. Here, we demonstrate the successful fabrication of highly oriented nanowire arrays of fullerene (C₆₀) via directional polymerization, mediated by grazing incidence of high-energy charged particles. These C₆₀ nanowires exhibit remarkably high electrical conductivity, comparable to that of undoped germanium, which is attributed to a unique polymerization process induced by particle irradiation. Field-effect transistor (FET) measurements revealed that electrons serve as the primary charge carriers in the nanowires. Temperature-dependent electrical measurements further indicate that the conduction mechanism follows a thermally activated hopping process, rather than conventional band conduction, reflecting the amorphous and crosslinked nature of the polymerized nanowires. Furthermore, a measurable change in conductivity upon nitrobenzene adsorption suggests their potential application as highly sensitive, electron-based organic gas sensors.