Yellow emission is crucial in RGBY display technology and in fabricating physiologically friendly, low color‐temperature lighting sources. Emitters with both wet‐ and dry‐process feasibility are highly desirable to fabricate, respectively, high‐quality devices via vapor deposition and cost‐effective, large‐area devices via roll‐to‐roll fabrication. Here, high‐efficiency organic light‐emitting diodes with a novel wet‐ and dry‐process feasible yellow‐emitting iridium complex, bis[5‐methyl‐7‐fluoro‐5H‐benzo(c)(1,5) naphthyridin‐6‐one]iridium (picolinate), are demonstrated. By spin coating, the device shows, at 1000 cd m−2, an external quantum efficiency (EQE) of 18.5% with an efficacy of 52.3 lm W−1, the highest among all reported yellow devices via wet‐process, while using vapor deposition, the EQE is 22.6% with a 75.1 lm W−1 efficacy, the highest among all dry‐processed counterparts. The high efficiency may be attributed to the replacement of the hydrogen atom with a fluorine atom on a 2‐substitutional site in the emitter to prevent dense molecular packing‐caused self‐quenching and to reduce radiationless deactivation rates, leading to a high quantum yield (71%).

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High efficiency green emission is crucial to the designs of energy‐saving display and lighting. Efficient electroluminescent green emitters with both wet‐ and dry‐process feasibility is highly desirable in order to realize, respectively, cost‐effective large roll‐to‐roll manufacturing and high performance products. In this study, high‐efficiency, phosphorescent, green organic light emitting diodes with a novel iridium complex, bis[5‐methyl‐8‐trifluoromethyl‐5H‐benzo(c)(1,5)naphthyridin‐6‐one] iridium (acetylacetonate), are demonstrated. They possess both wet‐ and dry‐processing possibilities. The emitter exhibits a short excited‐state lifetime, 1.25 μs, and a high quantum yield, 69%, due to the efficient intersystem crossing of the ground state to the excited state. Using 4,4′‐bis(carbazol‐9‐yl)biphenyl as a host, the device shows at 1000 cd m−2 an external quantum efficiency (EQE) of 21% and power efficiency of 64 lm W−1 via vapor deposition, while 26% EQE and 69 lm W−1 by spin‐coating, the highest among all reported wet‐processed green organic light emitting diodes. Besides electroluminescence, the high device efficiency may also be attributed to the employed device architecture enabling therein an electron trap to facilitate the injection of this minor carrier against that of a hole, leading to a balanced carrier‐injection, and hence a high carrier recombination and in turn a high device efficiency.

Yellow emission plays an important role in many display and lighting applications, such as RGBY display or blue hazard free lighting sources, while a wet-process enables soft devices to be manufactured cost-effectively.