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Emissive organic semiconductors are highly demanding for organic light‐emitting transistors (OLETs) and electrically pumped organic lasers (EPOLs). However, it remains a great challenge to obtain organic semiconductors with high carrier mobility and high photoluminescence quantum yield simultaneously. Here, a new design strategy is reported for highly emissive ambipolar and even n‐type semiconductors by introducing perfluorophenyl groups into polycyclic aromatic hydrocarbons such as perylene and anthracene. The results reveal that 3,9‐diperfluorophenyl perylene (5FDPP) exhibits the ambipolar semiconducting property with hole and electron mobilities up to 0.12 and 1.89 cm2 V−1 s−1, and a photoluminescence quantum yield of 55%. One of the crystal forms of 5FDPA exhibits blue emission with an emission quantum yield of 52% and simultaneously shows the n‐type semiconducting property with an electron mobility up to 2.65 cm2 V−1 s−1, which is the highest value among the reported organic emissive n‐type semiconductors. Furthermore, crystals of 5FDPP are utilized to fabricate OLETs by using Ag as source–drain electrodes. The electroluminescence is detected in the transporting channels with an external quantum efficiency (EQE) of up to 2.2%, and the current density is up to 145 kA cm−2, which are among the highest values for single‐component OLETs with symmetric electrodes. [ABSTRACT FROM AUTHOR]

Organic semiconductors with combinative high carrier mobility and efficient solid‐state emission are full of challenges but urgently pursued for developing new emerging optoelectronics. Herein, by delicately regulating the crystal packing of an anthracene‐based molecular crystal via terminal tert‐butylation, we developed a superior high mobility emissive molecule, 2,6‐di(6‐tert‐butylnaphthyl)anthracene (TBU‐DNA). The unique "slipped herringbone" packing motif of TBU‐DNA enables its appropriate exciton‐exciton coupling and electron‐phonon coupling, thus resulting in remarkably high solid‐state emission (photoluminescence quantum yield, ΦF≈74.9 %) and efficacious charge transport (carrier mobility, μ=5.0 cm2 V−1 s−1). Furthermore, OLETs based on TBU‐DNA show an external quantum efficiency (EQE) of 1.8 %, which is among the highest EQE values for single component OLETs reported till now. This work presents a crystal engineering strategy via exquisite molecular design to realize high mobility emissive organic semiconductors. [ABSTRACT FROM AUTHOR]

The development of high mobility organic laser semiconductors with strong emission is of great scientific and technical importance, but challenging. Herein, we present a high mobility organic laser semiconductor, 2,7‐diphenyl‐9H‐fluorene (LD‐1) showing unique crystallization‐enhanced emission guided by elaborately modulating its crystal growth process. The obtained one‐dimensional nanowires of LD‐1 show outstanding integrated properties including: high absolute photoluminescence quantum yield (PLQY) approaching 80 %, high charge carrier mobility of 0.08 cm2 V−1 s−1, Fabry‐Perot lasing characters with a low threshold of 86 μJ cm−2 and a high‐quality factor of ≈2400. Furthermore, electrically induced emission was obtained from an individual LD‐1 crystal nanowire‐based light‐emitting transistor due to the recombination of holes and electrons simultaneously injected into the nanowire, which provides a good platform for the study of electrically pumped organic lasers and other related ultrasmall integrated electrical‐driven photonic devices. [ABSTRACT FROM AUTHOR]