Optimising Energy Transfer in Hyperfluorescence

ended

With an ever-growing population, reducing our demand for energy is a key challenge in building a sustainable future. As part of tackling this problem, Organic Lighting-emitting Diodes (OLEDs) show great potential for application in low-energy consumption displays, lighting, and lasers. OLEDs are increasingly featured in high end consumer electronics; however, their potential is yet to be realised. Undoubtedly, the largest problem OLEDs face today is the instability of the blue emitter. Commercial OLEDs currently employ either an inefficient but stable blue emitter (resulting in energy wastage) or an efficient but unstable blue emitter (resulting in short-lived devices). By splitting the task of energy conversion and emission between two molecules within a device, stable and efficient blue emission is achievable. However, the current approach is to disperse these two molecules within a host, which leads to unpredictable orientations and distances between molecules. This results in detrimental processes within the device that reduce both efficiency and lifetime. Traditionally thought to be a device engineering problem, I propose a step change in thought. In a new approach to molecule design, I aim to tether the molecules together using a rigid bridging unit, forming a ‘dyad’ which gives precise control over the orientation and distances within a device. I aim to explore the efficiency of energy transfer as a function of the bridging unit to develop a structure-function relationship. The results of this work will establish design criteria for dyads which will facilitate the development of both efficient and stable blue emitters.