Electrochemical Gating of Aligned Single-Walled Carbon Nanotube Network

Abstract

Electrochemical gating of carbon nanotubes has recently gained much attention due to its high gating efficiency and its potential application as ionic sensors. However, electrochemical gating effects of single-walled carbon nanotube (SWNT) networs have not been reported. Here, we report on the electrochemical gating effect of aligned SWNT network field-effect transistors. First, SWNTs were dispersed in dichlorobenzene by ultrasonc aggitation, then the solution was dropped on a pre-fabricated interdigitated electrodes(IDEs). The SWNTs were aligned between IDEs by AC dielectrophoresis with 10Vpp, 5MHz AC electric-field applied between the source and drain electrodes. The alinged SWNT network was stablized by applying 5 V, 1 ms voltage pulses between the electrodes that removed unstable connections. A 10 mM NaCl electrolyte solution was dropped on the sample and the electrolyte potential was modified using Ag electrodes. At positive gate voltages the current transport through the device was suppressed. As the applied electrolyte gate voltage increased in the negative direction the current through the device was also increased. We will present electrochemical gating of aligned SWNT networks with differing SWNT density and electrolyte concentrations.