Template-Based Synthesis of Aligned Carbon Nanotube Arrays for Microfluidic and Nanofluidic Applications

Abstract

A multifunctional nanofluidic device consisting of an array of aligned carbon nanotubes (CNTs) was fabricated. A template-based method was employed to manufacture the CNT array without the need for nanoassembly. The CNT synthesis was done inside the pores of anodized aluminum oxide (AAO) membranes using a chemical vapor deposition (CVD) process. The tips of the CNTs were partially exposed through a sodium hydroxide etching process. The wall thickness and inner and outer diameters of the resultant CNTs were determined by scanning electron microscopy (SEM). Fluid flow through the CNT array was observed and the pressure drop across the membrane was measured as a function of fluid flow rate and CNT inner diameter. Nanochannel wettability was then evaluated as a function of carbon deposition and wet etching time. The work demonstrates the feasibility of creating a device, consisting of an array of vertically-aligned CNTs, capable of simultaneously measuring electrical signals and transferring fluid through conductive nanotubes.