This Small Business Innovation Research (SBIR) Phase I project aims to develop transparent electrodes based on silver nanowires and polymer substrates to replace indium tin oxide for applications in thin-film and flexible electronic devices. The approach is to form a silver nanowire-polymer composite with sheet resistance and transmission comparable to indium tin oxide coated on glass. A transfer technique will be employed to produce smooth electrode surface free of protruding silver nanowires. The expected outcome of the project is a new transparent electrode technology, with less than 10 nm surface roughness, 85% transmission, and 10 ohm per square sheet resistance. The project will also demonstrate high-performance thin-film electronic devices based on the composite electrodes.
The broader/commercial impact of this project will be the potential to provide a viable alternative to indium tin oxide to reduce the production cost of important electronic devices such as organic light emitting diodes, thin-film solar cells, and liquid crystal displays. The combined markets for these devices represent a substantial growth opportunity in the near future. However, the rising cost of indium and the lack of flexibility of indium tin oxide have become a major challenge. In this project, new composite electrodes will be developed, which are anticipated to be low cost, flexible and even stretchable without compromising device performance.
National Science Foundation Award No. 1114047 Polyradiant Corp. Polyradiant Corp. developed a propriety process for transparent electrode based on silver nanowire-polymer composite, providing great potential in replacing indium-tin oxide and could find wide application in transparent electromagnetic shielding, touch screen, organic light emitting diode lighting and displays, and solar cells. The new transparent composite electrode addressesmain drawbacks from traditional transparent electrodes based on indium-tinoxide such as brittleness, hazardousand expensive starting material and high capital investment. The transparent electrode produced from our propriety process offers superior overall performance that no other material and process can match, including high transmittance, low surface resistance, low haze, low surface roughness and strong adhesion. The substrate can be varied from rigid, flexible to highly stretchable plastics. The low temperature ambient process can be easily implemented into a roll-to-roll manufacturing process and will be cost effective. During our phase I research period of this NSF SBIR project, tremendous technical progress has been made in multiple areas including synthesis and coating process of nanowires, new polymer formulations with improved optical/electrical/mechanical property. Blue, green and red of polymer light emitting devices were demonstrated with much higher efficiency and flexibility than control device from indium-tin oxide/glass. Electromagnetic shielding evaluation achieved satisfactory effectiveness by a touch screen manufacturer. Further customer validation is underway. Polyradiant Corp. is actively seeking collaborators to launch pilot/small scale production for transparent shielding films within a year, touch screen and organic light emitting diode based lighting and display products in the near future.
