Nanoelectrode Ensembles Consisting of Carbon Nanotubes
Gabrielle R. Dangel, Hope Kumakli, Connor E. Rahm, Ryan J. White, Noe T. Alvarez
Abstract
Incorporating the nanoscale properties of carbon nanotubes (CNTs) and their assemblies into macroscopic materials is at the forefront of scientific innovation. The electrical conductivity, chemical inertness, and large aspect ratios of these cylindrical structures make them ideal electrode materials for electrochemical studies. The ability to assemble CNTs into nano-, micro-, and macroscale materials broadens their field of applications. Here, we report the fabrication of random arrays of CNT cross-sections and their performance as nanoelectrode ensembles (NEEs). Single ribbons of drawable CNTs were employed to create the CNT-NEEs that allows easier fabrication of nanoscale electrodes for general electrochemical applications. Surface analysis of the prepared NEEs using scanning electron microscopy showed a random distribution of CNTs within the encapsulating polymer. Electrochemical testing via cyclic voltammetry and scanning electrochemical cell microscopy revealed voltametric differences from the typical macroelectrode response with the steady-state nature of NEEs. Finally, when the NEE was employed for Pb2+ detection using square-wave anodic stripping voltammetry, a limit of detection of 0.57 ppb with a linear range of 10–35 ppb was achieved.