Manipulation of Charge and Exciton Distribution Based on Blue Aggregation‐Induced Emission Fluorophors: A Novel Concept to Achieve High‐Performance Hybrid White Organic Light‐Emitting Diodes

The aggregation-induced emission (AIE) phenomenon is important in organic light-emitting diodes (OLEDs), for it can potentially solve the aggregation-caused quenching problem. However, the performance of AIE fluorophor-based OLEDs (AIE OLEDs) is unsatisfactory, particularly for deep-blue devices (CIEy < 0.15). Here, by enhancing the device engineering, a deep-blue AIE OLED exhibits low voltage (i.e., 2.75 V at 1 cd m−2), high luminance (17 721 cd m−2), high efficiency (4.3 lm W−1), and low efficiency roll-off (3.6 lm W−1 at 1000 cd m−2), which is the best deep-blue AIE OLED. Then, blue AIE fluorophors, for the first time, have been demonstrated to achieve high-performance hybrid white OLEDs (WOLEDs). The two-color WOLEDs exhibit i) stable colors and the highest efficiency among pure-white hybrid WOLEDs (32.0 lm W−1); ii) stable colors, high efficiency, and very low efficiency roll-off; or iii) unprecedented efficiencies at high luminances (i.e., 70.2 cd A−1, 43.4 lm W−1 at 10 000 cd m−2). Moreover, a three-color WOLED exhibits wide correlated color temperatures (10 690–2328 K), which is the first hybrid WOLED showing sunlight-style emission. These findings will open a novel concept that blue AIE fluorophors are promising candidates to develop high-performance hybrid WOLEDs, which have a bright prospect for the future displays and lightings.

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