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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]

As a novel family of 2D materials, MXenes have drawn intensive interests owing to its fascinating property profile. The ability to grow high‐quality MXenes in a controllable way would in turn further promote the development of fabrication techniques and expand wide advanced applications. Then 2D MXenes crystals are highly desirable and many approaches have been explored to realize the mass production. Chemical vapor deposition (CVD) provides compelling benefits over other alternatives in controllability, uniformity and scalability. In this review, the recent advances in growth of MXenes crystals by CVD method will comprehensively present. Several typical kinds of MXenes crystals are demonstrated to be fabricated with a precise control in terms of size, morphology and thickness. Further, a series of MXenes heterostructures are constructed including vertical and lateral spatial orientations. Then, the properties and applications of MXenes crystals are exhibited, of which superconductivity and electrochemical catalysts will be mainly emphasized. Finally, the authors put forward views on the future development in the synthesis of MXenes. With continuous efforts devoted, a bright future of MXenes crystals prepared by CVD is expected. [ABSTRACT FROM AUTHOR]

Organic semiconductor crystals (OSCs) present better charge transport characteristics than organic semiconductor films. OSCs have captured worldwide attention because they show great potential for optoelectronic devices, including organic field-effect transistors, active-matrix organic light-emitting diodes, radio frequency identification tags, and sensors. Well-patterned OSCs minimize crosstalk between neighboring devices and decrease leakage current. Therefore, patterning OSCs offers more opportunities for advanced optoelectronic applications. In this work, OSC patterning strategies, advances in applications based on well-patterned OSCs, and challenges and outlooks in the field are discussed. [ABSTRACT FROM AUTHOR]

Cocrystals of 4-styrylpyridine and 1,2,4,5-tetracyanobenzene were successfully prepared by supramolecular self-assembly. Donor-acceptor interactions between the molecular components are the main driving force for self-assembly and contribute to intermolecular charge transfer. The cocrystals possess two-photon absorption properties that are not observed in the individual components; suggesting that two-photon absorption originates from intermolecular charge-transfer interactions in the donor-acceptor system. The origin of two-photon absorption in multichromophore systems remains under-researched; thus, the system offers a rare demonstration of two-photon absorption by cocrystallization. Cocrystal engineering may facilitate further design and development of novel materials for nonlinear optical and optoelectronic applications. [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]

[Display omitted] Tissue-equivalent pure organic semiconducting crystals (OSCs) have unique advantages in direct X-ray detectors (DXDs), especially for biological tissue fluoroscopy, but their low carrier mobility and inherent weak absorption restrict the limit-of-detection (LoD) and sensitivity of DXDs. High-mobility OSCs theoretically facilitate charge collection and performance leaps, however, they are rare and suffer from poor solubility due to high conjugation, leading to nearly impossible crystal growth from solution and subsequent device applications. Here we report an ingenious solution-processed crystal-growth and high-performance DXD using 2,6-diphenylanthracene (2,6-DPA), a high-mobility OSC we developed recently. In contrast to previous OSCs, high-mobility 2,6-DPA exhibits low dark current density and large photoconductive gain, resulting in record-breaking LoD of <85 nGy air s−1 and sensitivity of >103 μC Gy air −1 cm−2. Compared with semiconductors containing high- Z atoms (Z is atomic number), the accuracy of 2,6-DPA based DXDs is not affected by near-edge absorption effects. Moreover, the non-linear relationship between irradiation current and dose rate is confirmed as a high injection effect. High mobility and ingenious crystal growth strategy make 2,6-DPA an ideal active material for DXDs and also provide the possibility for more optoelectronic applications. [ABSTRACT FROM AUTHOR]