D. O’Carroll, C. Carter, Z. Shen, J. Tracey, C. Antonick
Keywords: OLEDs, stability, lifetime, cost, sustainability, embodied energy
Summary:Display and lighting technologies that use organic light-emitting materials are emerging as energy-efficient, versatile alternatives to liquid-crystal displays and inorganic light-emitting diode (LED)-based lighting. LEDs made entirely of inorganic compound semiconductor materials typically have large material embodied energies (due to high temperature and high energy-use fabrication processes) and are not compatible with the natural environment after degradation and being discarded (more than 50% of light sources are disposed of to landfills). OLEDs are being investigated as alternatives in order to create devices with low embodied energies that can decompose after use without significant harm to the environment. However, blue organic light-emitting devices exhibit operational lifetimes that are more than an order or magnitude shorter than green and red emitting devices, which limit their commercial use. Here we will present our research on different fluorescent and phosphorescent OLED device architectures that can be used to improve stability, cost and sustainability metrics such as operational lifetime, device cost, yearly operating cost, operating energy consumption per unit area, embodied CO2 emissions, and yearly operating CO2 emissions. Additionally, prospects for increasing blue light-emitting device operational lifetime using radiative decay rate engineering and by increasing light extraction efficiency using nanophotonic structures will be discussed.