Extremely stable-color flexible white organic light-emitting diodes with efficiency exceeding 100 lm W−1
Abstract
A flexible white organic light-emitting diode (WOLED) based on a polyethylene naphthalate (PEN) substrate has been developed, simultaneously achieving extremely high efficiency and extremely stable color. By using a superior combination of mechanical, electrical and optical properties, the resultant flexible WOLED can exhibit a maximum forward-viewing power efficiency (PE) of 101.3 lm W−1, 77.0 lm W−1 at 100 cd m−2, which remains as high as 58.2 lm W−1 at 1000 cd m−2. Besides, the device exhibits an excellent color-stability with a Commission International de L'Eclairage variation of (0.004, 0.005) when the luminance increases from 100 cd m−2 to 10 000 cd m−2. Moreover, the origin of the high efficiency and stable color has been comprehensively unveiled. The presented results provide an effective way to realize high-performance flexible WOLEDs.