Percolation in Transparent and Conducting Carbon Nanotube Networks

TLDR

The study explores avenues to enhance the conductance of carbon nanotube networks. Ultrathin, uniform single‑walled carbon nanotube networks of varying densities were fabricated at room temperature using vacuum filtration. Sheet conductance measurements revealed 2D percolation behavior, while transparency measurements matched thin‑film theory (σac = σdc at 550 nm), demonstrating the films’ suitability as transparent conductive coatings.

Abstract

Ultrathin, uniform single-walled carbon nanotube networks of varying densities have been fabricated at room temperature by a vacuum filtration method. Measurements of the sheet conductance as a function of nanotube network density show 2D percolation behavior. In addition, the network transparency in the visible spectral range was examined and the results are in agreement with a standard thin-film model: fits to the standard theory indicate σac = σdc for transmission measurements at 550 nm. Transmission measurements also indicate the usefulness of nanotube network films as a transparent, conductive coating. Avenues for improvement of the network conductance are discussed.