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Organic semiconductor single crystals, with the unique advantages of high carrier transport properties, high optical quality, and low defect density, are ideal candidates for constructing high‐performance organic light‐emitting transistors (OLETs) and advancing their related potential applications, including smart displays, micro‐nano light sources, organic electrically pumped lasers, and integrated photonic circuits. Recently, significant progress has been made in organic semiconductor single‐crystal light‐emitting transistors (OSSCLETs), particularly high‐mobility emissive organic semiconductor single crystals, high‐performance light‐emitting transistors, and color‐tunable organic semiconductor single crystals and OLETs. In this review, the exciting advances in OSSCLETs are summarized in terms of advanced organic semiconductor materials, high‐quality organic semiconductor single crystals, advanced device technologies, and high‐performance light‐emitting transistors. Finally, the challenges and prospects of OSSCLETs as well as promising research directions in this field are briefly summarized. [ABSTRACT FROM AUTHOR]

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]

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]

Keywords: Charge Transport; Crystal Engineering; Light Emission; Molecular Crystals; Organic Semiconductor EN Charge Transport Crystal Engineering Light Emission Molecular Crystals Organic Semiconductor 1 1 1 11/03/22 20221107 NES 221107 B An anthracene-based molecular crystal b with a unique "slipped herringbone" packing motif was developed by crystal engineering through terminal I tert i -butylation. Appropriate exciton-exciton coupling/electron-phonon coupling originating from the unique crystal packing induces a remarkably strong solid-state emission and efficient charge transport, as reported by Wenping Hu et al. in their Research Article (e202206825). Appropriate exciton-exciton coupling/electron-phonon coupling originating from the unique crystal packing induces a remarkably strong solid-state emission and efficient charge transport, as reported by Wenping Hu et al. in their Research Article (e202206825). [Extracted from the article]

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]

Field‐effect transistors are the fundamental building blocks for electronic circuits and processors. Compared with inorganic transistors, organic field‐effect transistors (OFETs), featuring low cost, low weight, and easy fabrication, are attractive for large‐area flexible electronic devices. At present, OFETs with planar structures are widely investigated device structures in organic electronics and optoelectronics; however, they face enormous challenges in realizing large current density, fast operation speed, and outstanding mechanical flexibility for advancing their potential commercialized applications. In this context, vertical organic field‐effect transistors (VOFETs), composed of vertically stacked source/drain electrodes, could provide an effective approach for solving these questions due to their inherent small channel length and unique working principles. Since the first report of VOFETs in 2004, impressive progress has been witnessed in this field with the improvement of device performance. The aim of this review is to give a systematical summary of VOFETs with a special focus on device structure optimization for improved performance and potential applications demonstrated by VOFETs. An overview of the development of VOFETs along with current challenges and perspectives is also discussed. It is hoped that this review is timely and valuable for the next step in the rapid development of VOFETs and their related research fields. [ABSTRACT FROM AUTHOR]

The development of blue‐emissive ambipolar organic semiconductor is an arduous target due to the large energy gap, but is an indispensable part for electroluminescent device, especially for the transformative display technology of simple‐structured organic light‐emitting transistor (SS‐OLET). Herein, we designed and synthesized two new dibenzothiophene sulfone‐based high mobility blue‐emissive organic semiconductors (DNaDBSOs), which demonstrate superior optical property with solid‐state photoluminescent quantum yield of 46–67 % and typical ambipolar‐transporting properties in SS‐OLETs with symmetric gold electrodes. Comprehensive experimental and theoretical characterizations reveal the natural of ambipolar property for such blue‐emissive DNaDBSOs‐based materials is ascribed to a synergistic effect on lowering LUMO level and reduced electron injection barrier induced by the interfacial dipoles effect on gold electrodes due to the incorporation of appropriate DBSO unit. Finally, efficient electroluminescence properties with high‐quality blue emission (CIE (0.179, 0.119)) and a narrow full‐width at half‐maximum of 48 nm are achieved for DNaDBSO‐based SS‐OLET, showing good spatial control of the recombination zone in conducting channel. This work provides a new avenue for designing ambipolar emissive organic semiconductors by incorporating the synergistic effect of energy level regulation and molecular‐metal interaction, which would advance the development of superior optoelectronic materials and their high‐density integrated optoelectronic devices and circuits. [ABSTRACT FROM AUTHOR]

The development of blue‐emissive ambipolar organic semiconductor is an arduous target due to the large energy gap, but is an indispensable part for electroluminescent device, especially for the transformative display technology of simple‐structured organic light‐emitting transistor (SS‐OLET). Herein, we designed and synthesized two new dibenzothiophene sulfone‐based high mobility blue‐emissive organic semiconductors (DNaDBSOs), which demonstrate superior optical property with solid‐state photoluminescent quantum yield of 46–67 % and typical ambipolar‐transporting properties in SS‐OLETs with symmetric gold electrodes. Comprehensive experimental and theoretical characterizations reveal the natural of ambipolar property for such blue‐emissive DNaDBSOs‐based materials is ascribed to a synergistic effect on lowering LUMO level and reduced electron injection barrier induced by the interfacial dipoles effect on gold electrodes due to the incorporation of appropriate DBSO unit. Finally, efficient electroluminescence properties with high‐quality blue emission (CIE (0.179, 0.119)) and a narrow full‐width at half‐maximum of 48 nm are achieved for DNaDBSO‐based SS‐OLET, showing good spatial control of the recombination zone in conducting channel. This work provides a new avenue for designing ambipolar emissive organic semiconductors by incorporating the synergistic effect of energy level regulation and molecular‐metal interaction, which would advance the development of superior optoelectronic materials and their high‐density integrated optoelectronic devices and circuits. [ABSTRACT FROM AUTHOR]

The organic molecules combining light-emitting and charge-transporting property are highly expected. We designed and synthesized a pair of isomers, 2,6-diphenylfuro[2,3- b ]quinoxaline (26dPFQ) and 2,7-diphenylfuro[2,3- b ]quinoxaline (27dPFQ), and investigated effect of changing substituent position on molecule packing motif, conducting and luminescence feature of resulting materials. In CH 2 Cl 2 solution, both isomers, 26dPFQ and 27dPFQ, emit deep blue light with a wavelength of 422 nm and shows photoluminance quantum yield (PLQY) of 58.9% and 48.7%, respectively. In crystal, the 26dPFQ employs H-type packing motif and retains blue florescent emission with low PLQY (10.0%) while 27dPFQ adopts J-aggregated packing motif and shows enhanced green fluorescent emission with a PLQY of 55.0%. The organic light-emitting devices for both emitters show deep blue emission, the EL peak at 410 nm for 26dPFQ and 424 nm for 27dPFQ, and respectively presents the maximum EQE of 1.2% and 1.0%. The 26dPFQ shows better charge transport capability over 27dPFQ. Our results suggested 2,6-substitution on furo[2,3- b ]quinoxaline core are expected to afford such dual functional materials. [Display omitted] • A pair of isomers, 2,6-diphenylfuro[2,3- b ]quionzaline (26dPFQ) and 2,7-diphenylfuro[2,3- b ]quionzaline (27dPFQ) were synthesized. • Both isomers emit deep blue light (422 nm), but the 2,6-position substituted isomer 26dPFQ shows better PLQY (58.9%) over 27dPFQ (48.7%) in solution. • The 26dPFQ, employing H-type packing motif and show significant better charge transport capability over 27dPFQ adopting J-aggregated packing. • 2,6-substitution on furo[2,3- b ]quionzaline core are expected to afford organic molecules combining light-emitting and charge-transporting property. [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]

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]