High-Efficiency Area-Emissive White Organic Light-Emitting Transistor for Full-Color Display

The construction of high-performance white organic light-emitting transistor (OLET) with uniform area emission is crucial for smart display technologies but remains greatly challenging. Herein, high-efficiency uniform area-emissive OLETs based on a unique lateral-integrated device configuration which incorporates efficient energy transfer of phosphorescent and fluorescent guests, enabling color-tunable and white emission, are demonstrated. Through precisely regulating the energy transfer between host and guests, high external quantum efficiency of 13.9% for white-emission OLETs is achieved due to the improved high exciton utilization and light outcoupling efficiency which is the highest value reported so far for OLETs and prevents exciton-charge annihilation and electrode photon losses. Moreover, good loop stability is also achieved, along with effective gate tunability and ultralow driving voltage of below 5 V. Finally, a 4 x 6 white-emission OLET array for full-color display is demonstrated for the first time, suggesting its great potential applications for advanced display technologies. Uniform area-emissive white OLET device with an efficiency of 13.9% is realized by incorporating phosphorescent blue emissive and fluorescent yellow emissive guests in the active layer based on a unique lateral-integrated device configuration, which is the highest value in the field and demonstrates great potential for full-color display as backlight source for the first time.image

Automated summary

This study demonstrates the construction of high-efficiency uniform area-emissive OLETs that enable color-tunable and white emission through efficient energy transfer. The OLETs achieve a high external quantum efficiency and exhibit good loop stability and low driving voltage.