Nanoscale Charge Percolation Analysis in Polymer‐Sorted (7,5) Single‐Walled Carbon Nanotube Networks

Abstract

The current percolation in polymer-sorted semiconducting (7,5) single-walled carbon nanotube (SWNT) networks, processed from solution, is investigated using a combination of electrical field-effect measurements, atomic force microcopy (AFM) and conductive AFM (C-AFM) techniques. From AFM measurements, the nanotube length in the as-processed (7,5) SWNTs network is found to range from ~100 nm to ~1500 nm, with a SWNT surface density well above the percolation threshold and a maximum surface coverage ≈ 58%. Analysis of the field-effect charge transport measurements in the SWNT network using a two-dimensional -2 -plane and reveal the isotropic nature of the as-spun (7,5) SWNT networks. This work demonstrates the tremendous potential of combining advanced scanning probe techniques with field-effect charge transport measurements for quantification of key network parameters including current percolation, surface coverage and degree of SWNT alignment. Most importantly, the proposed approach is general and applicable to other nanoscale networks, including metallic nanowires as well as hybrid nano-composites.

Large-area plastic nanogap electronics enabled by adhesion lithography

“…Three semiconductor types were investigated, namely the metal oxide semiconductor ZnO, the conjugated polymer F8BT and chirality selected PFO-wrapped semiconducting carbon nanotubes (PFO:CNT). 54 Figure 5a shows a schematic of the device architecture employed consisting of two symmetric Al/Al electrodes and a solution-processed semiconducting layer deposited on top. Figure 5b shows the low-voltage (−8 < V < 8 V) I-V scans for the three types of device.…”

“…The PFO:(5,7)CNT dispersion was prepared following the process described in refs. 54,64 and the respective chlorobenzene solution was spin-coated on the Al/Al nanogap electrodes followed by a mild annealing at 80°C to remove the solvent.…”

Modeling carrier density dependent charge transport in semiconducting carbon nanotube networks

“…Others investigated charge transport on a microscopic scale with, for example, conductive atomic force microscopy (c-AFM), and focused especially on segment and junction resistances. They found values of around 10 k μm −1 for nanotube segments and 10 2 -10 5 k for junctions [29,[35][36][37][38][39][40]. Most of these experiments investigated the role of metallic nanotubes within networks and the highly resistive Schottky barriers between metallic and semiconducting nanotubes.…”

Recent Advances in Applications of Sorted Single‐Walled Carbon Nanotubes

“…This pioneering work published by the leading authors has inspired researchers to advance this field. The main focus aims are improving the synthesis methods, enhancing the device performances, lowering the production cost and demonstrating new designs, and some of these studies included the composite materials based on SWCNTs …”