MICROFLUIDIC ASSEMBLY OF CARBON NANOTUBES INTO FUNCTIONAL NETWORKS

Abstract

Microfluidic devices are finding increasing applications as biomedical devices, tools for chemistry and biochemistry, assembly tools for nanoparticles, and systems for fundamental research. In this project, microchannel devices in poly(dimethylsiloxane) (PDMS) elastomer were built using rapid prototyping and replica molding techniques with SU-8™ negative photoresist. Inlet and outlet connections to these microchannels were made through capillary tubes. These microchannels will then be connected to pressure-driven shear flows of carbon nanotubes (CNTs) suspension by micropump with the attempt to align as many CNTs as possible with the flow. Before these processes, the CNTs were pretreated. The pretreatment included filtration to remove impurities and reduce the length of the CNTs; functionalization of the CNTs with the fluorophore DiOC16 to enhance the visualization. Flow of CNTs suspension inside the microchannels was studied showing that microfluidic assembly of CNTs is feasible. Degree of alignment of CNTs was also analyzed.