TADF Compounds

About

About The use of TADF emitters represents a paradigm shift in emitter development wherein inexpensive small molecule organic compounds can now be used to harvest 100% of the excitons in an electroluminescent device and so obtain excellent power efficiencies. We have developed a series of deep blue TADF emitters for Organic Light-Emitting Diodes (OLED). TADF allows purely organic emitters to harvest the triplet states as an alternative to the existing heavy-metal based phosphorescent OLEDs, which are known to be expensive and environmentally hostile. The emitters contain both carbazole donors and oxadiazole acceptors to effectively form excitons by a charge trapping mechanism. The blue colour emission wavelength of these emitters can be a valuable asset as there is currently a dearth of bright blue-emitting phosphorescent emitters for OLEDs. The invention is primarily used for blue-emitting OLEDs or, when operating in parallel with green and red emitters, for energy-efficient white lighting devices. Due to the nature of TADF, potential applications also include temperature or oxygen sensors. Key Benefits Harvesting 100% of excitons via TDF for OLED devices Inexpensive organic emitters Environmentally more benign Deep blue emission colour Ambipolar characteristic Applications Blue-emitting OLEDs To operate in parallel with red and green emitters for energy efficient white light devices Due to the nature of TADF, potential applications also include temperature or oxygen sensors IP Status Subject to UK patent application number 1507340.6 filed 29 April 2015.