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Perovskite quantum dots (PQDs) photoresists are promising building blocks for photolithographically patterned devices. However, their complex synthesis and combination processes limit their optical properties and potential patterning applications. Here, we present an exceptionally simple strategy for the synthesis of PQDs photoresist. Unlike traditional approaches that involve centrifugation, separation, and combination processes, our direct synthesis technique using polymerizable acrylic monomer as solvent to fabricate PQDs photoresists without complex post‐synthesis process. We demonstrate that the change in solubility of the precursors is the main reason for the formation of PQDs in the polymerizable monomer. By direct photolithography, colorful PQD patterns with high photoluminescence quantum yields and high thickness are successfully demonstrated. This work opens a new avenue for the direct synthesis of PQDs photoresist, expanding their applications in various integrated applications, such as photonic, energy harvesting, and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Precise pixel control of quantum dots (QDs) offers unparalleled opportunities for various display applications, such as the OLED and Micro-LED. However, precise selective patterning of QDs is still a challenge due to the lack of a design methodology. Therefore, the aim of this study was thus to develop a photoinitiator-grafted oligomer for "on demand" control of active free radicals to improve the line edge roughness in QD patterning. This photosensitive oligomer was constructed by grafting the photosensitive benzophenone structure onto a phenolic resin oligomer, thus resulting in the confinement of active free radicals and highly selective photolithography. As a proof of concept, we have demonstrated high-quality QD patterns with high resolution and low edge roughness by using direct in situ photolithography. This work opens an avenue for the precise design and synthesis of QD photoresists, improving the precision of QD patterning for display applications. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) have become the most valuable luminescent materials due to their excellent optical properties, such as high color purity, high photoluminescence quantum yield (PLQY), and tunable luminescence spectra. QDs‐based display devices have been used commercially and have shown outstanding advantages such as wide color gamut, high brightness, etc. However, for high‐end displays such as micro‐light‐emitting diodes (Micro‐LED), fine precise patterning of QDs is still a prerequisite and key challenge. Recently, direct photolithography, a method based on photochemical reactions of QDs photoresist (QDPR), has been considered as the most potential patterning technology to achieve high resolution and high‐throughput. This review focuses on the recent progress of QDPR from the point of view of different photochemical reaction mechanisms: starting the monomer polymerization, followed by the ligand crosslinking or decomposition, and eventually introducing crosslinking additives. Furthermore, a comprehensive overview of the current applications of QDPR in displays is provided based on the different types of LED devices. Finally, existing problems in QDs direct photolithography are discussed, along with possible reasons and solutions. This review is expected to accelerate the development of direct photolithography patterning method and provide general guidance for the further design of QDPR for high‐end displays. [ABSTRACT FROM AUTHOR]

The heavy use of toxic and volatile solvents such as dimethylformamide (DMF) and dimethylsulfoxide (DMSO), in the chemical synthesis of perovskites is known to pose several sustainability challenges that significantly hinder their mass production for commercial applications. Herein, a polymerizable monomer solvent (4‐acryloylmorpholine, ACMO) is introduced that permits the growth and optical lithography of perovskite quantum dots (PQDs) through in situ polymerization. Morphological, structural, and optical analyses show that this polymerizable monomer can act both as a solvent to dissolve the perovskite precursor and as a monomer for photopolymerization reactions, allowing direct in situ fabrication and patterning of PQDs. By direct photolithography, colorful PQD patterns with high photoluminescent quantum yields, high resolution (minimum size of 5 µm), and excellent fluorescence uniformity, are successfully demonstrated. The work provides a new sustainable way of in situ patterning PQDs using polymerizable monomer solvents, leading to significant advances in various integrated applications, such as photonic, energy harvesting, and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Achieving high-performance circularly polarized organic room temperature phosphorescence (CPRTP) holds significant academic and industrial importance. Herein, a series of near-infrared, color-tunable, and long-lived CPRTP materials have been successfully constructed by doping achiral luminescent guests into chiral crystallizable hosts. Naphthalimide derivatives are chosen as the guest molecules owing to the large conjugation and good structure tunability. (−)-Di-p-toluoyl- L - and (+)-di-p-toluoyl- D -tartaric acid are selected as the host molecules on account of the outstanding chirality and crystallinity. Through doping naphthalimide into tartaric acid derivatives, the resultant materials show the desirable CPRTP with a luminescence dissymmetry factor equal to 1.14 × 10−2. The host stabilizes and protects triplet excitons generated from the guest and induces the chirality of phosphorescence. Impressively, the doping material is emissive in the near-infrared region of 720 nm, which has hardly been achieved before. By modifying the chemical structure of the guest, the phosphorescent color of doping materials can be well-modulated from green to yellow and red. Moreover, the doping material displays a lifetime of up to 2.14 s. It is highly anticipated that this work will provide a new design strategy for high-performance CPRTP materials. [ABSTRACT FROM AUTHOR]

Organic near‐infrared room temperature phosphorescence (RTP) materials offer remarkable advantages in bioimaging due to their characteristic time scales and background noise elimination. However, developing near‐infrared RTP materials for deep tissue imaging still faces challenges since the small band gap may increase the non‐radiative decay, resulting in weak emission and short phosphorescence lifetime. In this study, fused‐ring pyrrole‐based structures were employed as the guest molecules for the construction of long wavelength emissive RTP materials. Compared to the decrease of the singlet energy level, the triplet energy level showed a more effectively decrease with the increase of the conjugation of the substituent groups. Moreover, the sufficient conjugation of fused ring structures in the guest molecule suppresses the non‐radiative decay of triplet excitons. Therefore, a near‐infrared RTP material (764 nm) was achieved for deep penetration bioimaging. Tumor cell membrane is used to coat RTP nanoparticles (NPs) to avoid decreasing the RTP performance compared to traditional coating by amphiphilic surfactants. RTP NPs with tumor‐targeting properties show favorable phosphorescent properties, superior stability, and excellent biocompatibility. These NPs are applied for time‐resolved luminescence imaging to eliminate background interference with excellent tissue penetration. This study provides a practical solution to prepare long‐wavelength and long‐lifetime organic RTP materials and their applications in bioimaging. [ABSTRACT FROM AUTHOR]

In an electronic (fermionic) system, these chiral edge states (CESs) allow inversely polarized carriers to propagate in opposite directions at the edge of the topological insulators, which is related to the time-reversal symmetry (TRS) in fermionic systems. However, in acoustic (bosonic) systems, unlike those exhibited by fermionic systems, since there is no inherent polarization, it is generally believed that the CESs protected by fermionic TRS with independent counter-propagating cannot be supported. Herein, a strategy that achieves the counter-propagating CESs in topological metamaterials with fermionic TRS is reported in a 3D acoustic system. First, we designed a Floquet evolution protocol to incorporate effective fermionic TRS. Furthermore, by utilizing metamaterials, we creatively employ two subwavelength structures, that is, a cavity structure for adjusting the phase shift and a tube structure for providing coupling, which allows the model to be miniaturized. Finally, our experiment verifies the effectiveness of our approach. Our research results enrich the knowledge of topological metamaterials in the field of topological physics and pave the way for exploring fermionic properties in bosonic systems. [ABSTRACT FROM AUTHOR]

In this work, we studied the effect of the different thickness buffer layer on the electrical characteristics of InZnO (IZO) transistors. We found that when a 20nm layer of indium‐aluminum‐zinc oxide (IAZO) was added as the buffer layer between S/D electrodes and the active layer, the IZO transistor exhibited optimum electrical performance, with a high on/off drain current ratio of 2.61 ×107, the field‐effect mobility (μFE) of 15.75 cm2/Vs, the subthreshold swing (SS) of 129.85 mV/decade, and the turn‐on voltage (VON) of ‐0.4 V. [ABSTRACT FROM AUTHOR]