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Perovskite quantum dots for light-emitting devices
摘要： Perovskite quantum dots (QDs) have been hotly pursued in recent decades owing to their quantum confinement effect and defect-tolerant nature. Their unique optical properties, such as high photoluminescence quantum yield (PLQY) approaching unity, narrow emission bandwidth, tunable wavelength spanning the entire visible spectrum, and compatibility with flexible/stretchable electronics, render perovskite QDs promising for next-generation solid lighting sources and information displays. Herein, the advances in perovskite QDs and their applications in LEDs are reviewed. Strategies to fabricate efficient perovskite QDs and device configuration, including material composition design, synthetic methods, surface engineering, and device optimization, are investigated and highlighted. Moreover, the main challenges in perovskite QDs of instability and toxicity (lead-based) are identified, while the solutions undertaken with respect to composition engineering, device encapsulation, and lead-replacement QDs are demonstrated. Meanwhile, perspectives for the further development of perovskite QDs and corresponding LEDs are presented.
关键词： device encapsulation,quantum confinement,Perovskite quantum dots,LEDs,instability,composition engineering,flexible electronics,photoluminescence,lead-replacement,stretchable electronics,toxicity,light-emitting devices
更新于2025-09-16 10:30:52
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Full-color persistent luminescence tuning: A marriage of perovskite quantum dots and lanthanide ions
摘要： In modern society, luminescent materials capable of emitting various colored lights are critically important for lighting and display systems. As a typical kind of luminescent materials, the persistent luminescence phosphors have been widely investigated as night-light vision materials due to their many significant applications such as emergency route signage and security signals, bio-labels, photocatalysts, anti-counterfeiting, optical sensors, and optical data storage. However, realizing multicolored persistent luminescence phosphors has been a long-standing challenge, thus posing a serious problem in their practical applications. In a recent publication in Angewandte Chemie International Edition, Prof. Xueyuan Chen and co-workers demonstrated a simple but effective approach to fine-tuning the persistent luminescence colors, based upon the composites of lanthanide ions doped CaAl2O4:Eu2+,Nd3+ (CAO) blue persistent phosphors with all-inorganic CsPbX3 (X = Cl, Br, and I) perovskite quantum dots (PeQDs). With the help of the radiative energy transfer from CAO blue persistent phosphors to CsPbX3 PeQDs, the persistent luminescence colors can be precisely controlled through tailoring of the PeQDs bandgap. The approach allowed access to full-spectrum persistent luminescence with wavelengths covering the entire visible spectral range by single-wavelength excitation, thus offering new opportunities for persistent luminescence materials in many important emerging applications.
关键词： persistent luminescence,lanthanide ions,full-color tuning,perovskite quantum dots
更新于2025-09-16 10:30:52
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Purcell-Enhanced Spontaneous Emission from Perovskite Quantum Dots Coupled to Plasmonic Crystal
摘要： Lead halide perovskite quantum dots (PQDs) have recently been proposed as scalable and color-tunable single emitters, but their slow spontaneous emission (1-10 ns) creates a mismatch with high-speed nanophotonic devices. Here we demonstrate Purcell enhanced emission rate in hybrid structure of PQDs coupled to plasmonic crystal at room temperature. A series of planar devices are produced in large scale via chemistry assembly using colloidal PQDs, Ag nanocubes and polyvinyl pyrrolidone (PVP) as building blocks. By varying the PVP spacer thickness as well as Ag nanocube surface density, a tunable photoluminescence enhancement is realized in both steady and time resolved measurements. We show a 3.5-fold enhancement in the total fluorescence intensity and simultaneously an increase in the emission rate of a factor of 4.5. Finally, a proof-of-concept tag using PVP spacer encoded inks is demonstrated, providing a promising approach for information security based on Purcell-enhanced emission.
关键词： perovskite quantum dots,plasmonic crystal,information security,spontaneous emission,Purcell-enhanced emission
更新于2025-09-16 10:30:52
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Nonvolatile photoelectric memory with CsPbBr3 quantum dots embedded in poly(methyl methacrylate) as charge trapping layer
摘要： Nonvolatile organic field-effect transistor (OFET) photoelectric memories have attracted tremendous attention due to special photoelectric memory mechanism and application area, such as image capture and light information storage. Unfortunately, conventional two-step preparation method of floating gate and tunneling layer is complex and not conducive to large-area. Here, a nonvolatile OFET photoelectric memory with perovskite quantum dots (QDs) embedded in poly(methyl methacrylate) (PMMA) as charge trapping layer is reported. The photoelectric memory can effectively accumulate and release photo-generated carriers during photo- or photoelectric programming operations and electrical erasing operation. The memory characteristics of the photoelectric memory are comparable to that of traditional memories with two-step preparation technique of floating gate and tunneling layer. In addition, the memory device presents well retention time and endurance property even after being exposed to air for two weeks. Hence, the memory using QDs/PMMA composites as charge trapping layer shows great potential for the application in photoelectric devices.
关键词： photoelectric memory,inorganic perovskite quantum dots,organic field-effect transistor
更新于2025-09-16 10:30:52
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In Situ Light-Initiated Ligands Crosslinking Enables Efficient All-Solution-Processed Perovskite Light-Emitting Diodes
摘要： Solution process has been considered to be an effective method to fabricate emitting layer (EML) in light-emitting diodes (LEDs). However, the fabrication of charge transport layer (CTL) above the perovskite EML by solution processing is challenging. Herein, we incorporated polymerizable molecules, conjugated linoleic acid (CLA), as surface ligands to passivate perovskite QDs. The polymerized CLA can create a crosslinked QD film, which allows the solution deposition of subsequent CTLs. The theoretical calculations reveal that the binding energy of polymerized CLA with QDs increased, and the strong ligands binding state can better passivate the surface and improve the stability of QDs. As a result, all-solution-processed multilayer perovskite LEDs were fabricated with performance of a max luminance of 2470 cd/m2 for CsPbBr3-based devices, and a peak EQE of 2.67% for CsPbI3-based devices. These results demonstrate that the in situ light-initiated ligands crosslinking can be an effective strategy in all-solution-processed optoelectronic devices.
关键词： optoelectronic devices,light-emitting diodes,solution processing,perovskite quantum dots,ligands crosslinking
更新于2025-09-16 10:30:52
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Reducing Photovoltage Loss in Inverted Perovskite Solar Cells by Quantum Dots Alloying Modification at Cathode Contact
摘要： The tremendous passion for inverted planar heterojunction perovskite solar cells (PSCs) is originated from their great tendency in the Roll-to-Roll process compatible fabrication and huge potential for integration into tandem solar cells. But the device efficiency is still lower than regular structured PSCs. Engineering of the cathode interface to efficiently control and reduce VOC loss light a lamp for increasing electrochemical properties and boosting overall performance. In this work, a simple interfacial modification strategy was developed by introducing a hybrid ligands interfacial layer to reduce VOC loss in PSCs with inverted planar structure. Heavily washed QDs was used as a neutral charged intermedia to enable alloying reaction to transfer ligands without damage perovskite. A band bending immediately generated on top surface of perovskite film after QDs modification, which was directly convinced by UPS and KPFM. This contributed to ~50 mV reduced VOC loss, leading to a VOC of 1.15 V and a PCE of 20.6% in inverted PSCs. Meanwhile, enhanced stability achieved for these devices after QDs modification, in which PCE keeping > 90% of initial value after 1000 hours' storage.
关键词： inverted planar heterojunction perovskite solar cells,perovskite quantum dots,photovoltage,electron transport layer,passivation
更新于2025-09-12 10:27:22
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Exploring Orbit–Orbit Interaction in Relationship to Photoluminescence Quantum Efficiency in Perovskite Quantum Dots through Rashba Effect
摘要： This study demonstrates the influence of orbit-orbit interaction on photoluminescence quantum efficiency (PLQE) of metal halide perovskite quantum dots (QDs) through Rashba effect. The orbit-orbit interaction between excitons was characterized by using the minimal excitation intensity required to generate photoluminescence difference (?PL) between linearly and circularly polarized photoexcitations. It was observed that changing the surface functionalization from PFOA-OA to PFSH-OAm and OA can largely increase the minimal excitation intensity for generating ?PL. This indicates that orbit-orbit interaction is essentially decreased in CsPbBr1I2 QDs with surface functionalization. Simultaneously, the PLQE is increased from 39 % to 59 % and 72 % in CsPbBr1I2 QDs upon surface functionalization. Furthermore, the PL lifetime is decreased with increasing the PLQE in CsPbBr1I2 QDs upon surface functionalization. This phenomenon implies that decreasing the orbit-orbit interaction can essentially weaken Rashba effect and consequently reduces the disallowed transitions, leading to an enhancement on PLQE in perovskite QDs.
关键词： Rashba effect,orbit-orbit interaction,Perovskite quantum dots,photoluminescence quantum efficiency
更新于2025-09-12 10:27:22
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Inkjet‐Printed Micrometer‐Thick Patterned Perovskite Quantum Dot Films for Efficient Blue‐to‐Green Photoconversion
摘要： Perovskite materials have attracted great attention as a potential color conversion material in the display field recently. However, preparing a large and thick patterned film remains to be a key challenge. Here, a patterned CsPbBr3 quantum dot color conversion layer is prepared using the inkjet-printing and UV-curing method. The prepared 6 μm film exhibits a uniform morphology without coffee-ring effect. Green emission is achieved with a brightness of 58 cd m?2 and narrow emission band is achieved using the 345 cd m?2 blue OLED excitation light. Furthermore, only 1.4% of decay in brightness is observed after the film is exposed to ambient environment for 1 month without any protection. Finally, a 6.6 in. active matrix perovskite quantum dot display prototype is demonstrated using the blue OLED backlight with 384 × 300 resolution for the first time.
关键词： color conversion,displays,inkjet printing,perovskite quantum dots
更新于2025-09-12 10:27:22
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Novel Bromide Quaternary Ammonium Ligand for Synthesizing High Fluorescence Efficiency CsPbBn Perovskite Quantum Dots and Their Fabrication of White Light-Emitting Diodes with Wide Color Gamut
摘要： We proposed a novel bromine quaternary ammonium ligand to synthesize high quantum yield (QY) CsPbBr3 quantum dots (QDs). The QY of CsPbBr3 QDs synthesized by this ligand reached 95% and the full width at half maximum (FWHM) was as narrow as 17nm. The peak wavelength of the prepared CsPbBr3 QDs was 530nm. And these QDs emitted high purity green light under ultraviolet light. The color coordinate of white LED (WLED) prepared with the CsPbBr3 QDs was (0.29, 0.31), which was very close to pure white light. The color gamut of the WLED covered 130% of the national television system committee (NTSC) color standard and 96% of the ITU-R Recommendation BT.2020 (Rec.2020) color standard.
关键词： CsPbBr3 Perovskite Quantum Dots,Bromide Quaternary Ammonium Ligand,Wide Color Gamut,White Light-Emitting Diodes
更新于2025-09-12 10:27:22
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Perovskite Quantum Dots Exhibiting Strong Hole Extraction Capability for Efficient Inorganic Thin Film Solar Cells
摘要： Inorganic semiconductor Sb2(S,Se)3 possesses a suitable bandgap, environmentally benign elemental composition, and excellent stability, offering ample promise for next-generation low-cost solar cells. Here, we demonstrate that perovskite quantum dots (QDs), including CH3NH3PbBr3 and CsPbBr3, can serve as highly efficient and air-stable hole extraction materials in Sb2(S,Se)3 solar cells. Through a proper pre-treatment of the colloidal QDs, a 25-nm-thick QD film can be obtained with excellent uniformity and charge transport properties. Spectroscopic and photoelectrochemical analysis show that perovskite QDs can effectively extract holes from Sb2(S,Se)3 with suppressed carrier recombination. The perovskite QDs/Sb2(S,Se)3 heterojunction also establishes an increased built-in potential so that open-circuit voltage is pronouncedly enhanced. Finally, the device based on perovskite QDs/Sb2(S,Se)3 heterojunction boosts the efficiency from 4.43% to 7.82%, setting a record value, to the best of our knowledge, in Sb2(S,Se)3 solar cells. Our research manifests another application of perovskite materials and practical strategy toward efficiency improvement of Sb2(S,Se)3 solar cells.
关键词： efficiency improvement,inorganic thin film solar cells,Perovskite quantum dots,Sb2(S,Se)3,hole extraction
更新于2025-09-12 10:27:22