I-Corps: Materials for Organic Light Emitting Diodes

Mississippi State University, Mississippi State MS

Investigators

Abstract

The broader impact/commercial potential of this I-Corps project is in the arena of energy-efficient solid state lighting. It has been estimated that 20% of all electricity generated in the US is for lighting purposes. Solid state lighting uses far less energy to produce the same amount of effective lighting than incandescent or fluorescent bulbs. Additionally, it neither poses the environmental risk of releasing elemental mercury, nor does it require restricted disposal as do compact fluorescent bulbs. Organic Light Emitting Diodes (OLEDs) are more energy efficient and flexible than simple Light Emitting Diodes (LEDs), which are made of brittle inorganic materials. OLEDs are >90% more efficient than incandescent light bulbs, and have the potential to be >98% more efficient. Therefore, OLED technology has the potential to dramatically reduce lighting costs and the associated electrical generation preventing the release of billions of tons of carbon dioxide into the atmosphere. OLED screens are steadily displacing other technologies used in portable, battery-operated devices such as cell phones, laptops, and tablets, and in TV's, airplane cockpits, and cars. This I-Corps project addresses a technological bottleneck for current OLED devices in the materials used for the generation of blue light. The materials currently in use have a fluorescent emission, which requires higher voltages resulting in greater energy consumption, more heat generation, and faster breakdown of the material in the device. Current manufacturers have adapted by using a layer of blue material that is twice the thickness of that in the red and green diode, which poses challenges for engineering the device structurally. The red and green diodes use a phosphorescent material requiring less voltage for generating the emission, thus, reducing energy consumption and heat generation. This project will evaluate the market potential of a new phosphorescent, true-blue emitting material for commercial applications that has greater thermal and chemical stability and is highly quantum efficient. During the project period, the team will gather information from OLED manufacturers to device makers to discern the need, cost-point, and interest for new raw materials, and how to fine tune the materials to better suit applications.