The innovation engine for new materials

Lucy Darago

Lucy Darago

University: 

University of California at Santa Barbara

Major: 

Chemistry

Site Abroad: 

Leibniz Institute for New Materials, Saarbrucken, Germany

Mentor(s): 

Dr. Sabine Heusing
Dr. Mario Quilitz

Faculty Sponsor(s): 

Dr. Peter Oliveira

Project Title: 

Single-walled carbon nanotube-based transparent conductive coatings

Project Description: 

Transparent conductive materials are key components of many devices such as organic light emitting diodes, liquid crystal displays, and solar cells. The brittleness and decreasing availability of the standard for transparent electronics, indium tin oxide (ITO), prompt a search for improved replacements. Carbon nanotube-based coatings are a possible alternative due to their high transparency in thin coatings and good conductivity. Conductivity in carbon nanotube coatings is achieved by a nanotube network, making the even dispersion of the nanotubes a key feature of good coatings. In this study, single-walled carbon nanotube (SWNT)-based coatings were investigated. Low concentration aqueous SWNT coatings and aluminium zinc oxide (AZO) and SWNT coatings were studied. Coatings of AZO mixed with SWNT were nonconductive. SWNT coatings were then layered with ITO coatings to try to improve conductivity of ITO coatings. An aqueous ITO and SWNT mixture was also attempted. All coatings were made by spin coating. The coatings were characterized by optical and electronic properties such as transparency, haze, and sheet resistance. Coating thickness was determined by ellipsometry. Two-layer aqueous SWNT coatings were observed to have transparency near 90% and sheet resistance near 450 ohms/square. These coatings had transparency comparable to that of ITO and sheet resistance lower than all other alternatives tested. Further studies must be done to achieve better dispersions of carbon nanotubes for superior coatings.