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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]

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]

White light-emitting diodes (WLEDs) based on all-inorganic perovskite CsPbX3 (X = Cl, Br, I) quantum dots (QDs) have attracted much attention and rely on mixing several colors of perovskites. However, this inevitably leads to a non-uniform light distribution and serious light loss. Here, a novel strategy was demonstrated to obtain white emission by combining the orange and blue emission from CsPb/Mn(Cl/Br)3 QDs. Notably, highly efficient white emission with a photoluminescence quantum yield of 94% was achieved by an anion exchange surface engineering (AESE) strategy. After AESE treatment the surface traps can be eliminated, resulting in improved exciton and Mn2+ emission. A prototype WLED device was fabricated and exhibited excellent optical stability, demonstrating great potential for perovskite QDs in the field of optoelectronics. [ABSTRACT FROM AUTHOR]

The tunable wavelength and high photoluminescence quantum yield of metal halide perovskite quantum dots (QDs) make them an extraordinary material for white light-emitting diodes (WLEDs). However, when perovskites with different halides are mixed, anion exchange occurs between them, limiting the development of WLEDs based on the perovskite. Meanwhile, the red emitting perovskite containing iodine is not stable, which is also a problem to overcome. In this paper, only bromide perovskites were adopted to fabricate the WLED. Hence, the anion exchange reaction can be avoided during their mixing process. CsPbBr3 nanoplatelets, CsPbBr3 QDs, and Mn-doped PEA2PbBr4 nanosheets were used as the blue, green, and red components of the WLEDs, respectively. All these perovskites preserve high luminance and stability, especially the red emitting component. Thus, the WLED shows high efficiency and excellent stability. By adjusting the amounts of these perovskites, WLEDs with different color temperatures were achieved, and the color rendering index reached up to 94. [ABSTRACT FROM AUTHOR]