NATURE
·
2025
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IF 48.5
Wu Qianqian,Cao Fan,Yu Wenke,Wang Sheng,Hou Wenjun,Lu Zizhe,Cao Weiran,Zhang Jiaqi,Zhang Xiaoyu,Yang Yingguo,Jia Guohua,Zhang Jianhua,Yang Xuyong
The electroluminescence performance of heavy-metal-free blue quantum dot (QD) light-emitting diodes (QLEDs) is much lower than that of state-of-the-art cadmium-based counterparts. Ecofriendly ZnSeTe QDs are an ideal alternative to cadmium-based blue QDs 1 , 2 , but face issues with colour impurity and inferior stability caused by the aggregated tellurium (Te n ≥2 ) that dominates compositional inhomogeneity 3 , 4 . Here we developed an isoelectronic control strategy using congeneric sulfur coordinated with triphenyl phosphite (TPP-S) to construct homogeneous ZnSeTeS QDs with pure-blue emissions and near-unity photoluminescence quantum yield. TPP with low electron-donating capability promotes the reactivity balance among anionic precursors, favouring the growth of QDs with uniform composition. The acceptor-like S with high electronegativity weakens the hole localization of the Te atoms by interfering with their surrounding carriers, thereby suppressing the formation of Te n ≥2 isoelectronic centres. Furthermore, the congeneric S increases the configurational entropy of the QDs and eliminates the stacking faults and oxygen defects, leading to improved structural stability and reduced non-radiative carrier density. Consequently, the resulting pure-blue QLEDs based on core–shell ZnSeTeS/ZnSe/ZnS QDs emitting at 460 nm show a high external quantum efficiency of 24.7%, a narrow linewidth of 17 nm, and long operational half-lifetime ( T 50 ) close to 30,000 hours at 100 cd cm −2 , rivalling state-of-the-art cadmium-based blue QLEDs.
研究领域:
材料科学
·
光电工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 7
·2980-2985
·
IF 3.288
Zhen Li,Li Li,Huali Liu,Fei Li,Jiaqi Zhao,Yu Wang
Mn2+-doped CsPbBr3 nanocrystals (NCs) within MCM-41 mesophase silica have been prepared via a template-assisted strategy by using MCM-41 as the template. The template-synthesized CsPb1−xMnxBr3 NCs (x = 0–1) with the investigated perovskite compositions are luminescent with 465 nm pure blue light. The coprecipitation of bulk materials can be controlled by varying the amount of Mn2+ doping because the formation energy of CsPbBr3 NCs rises slightly on increasing the Mn2+ content and then decreases with the further increase in the Mn2+ content. Furthermore, they also exhibit excellent UV and air stability due to the existence of MCM-41 mesoporous silica and can be used as phosphors for solid-state lighting.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Wei Shen,Ye Yu,Wenzhu Zhang,Yanfeng Chen,Jianbin Zhang,Liu Yang,Jingting Feng,Gang Cheng,Lihui Liu,Shufen Chen
Exploitation of next-generation blue light-emitting diodes (LEDs) is the foundation of the revolution in lighting and display devices. Development of high-performance blue perovskite LEDs is still challenging. Herein, 4-aminobenzenesulfonic acid (SA) is introduced to passivate blue CsPbBr3 nanoplates (NPLs), reducing the ionic migration via a more stable Pb2+–SO3–– formation, and the trap state density of films shows a 50% reduction. The inevitable Br– vacancy defects after the multistep washing process can be suppressed by a suitable MABr treatment, which can boost the external quantum efficiency (EQE) performance. It should be noted that the coverage of NPL films is another key factor to realize reproducible pure blue electroluminescence (EL). Therefore, we proposed an alternate droplet/spin coating method to improve the coverage and thickness of NPL layer to prevent hole transport layer emission and increase the reproducibility of LED performance and spectra. Furthermore, we designed hole transport layers to decrease the hole transport barrier and improve the energy-level alignment. According to SA passivation, MABr treatment, alternate droplet/spin coating method, and device structure optimization, a CsPbBr3 NPL-based pure blue (0.138, 0.046) LED with 3.18% maximum EQE can be achieved, and the half-lifetime of EL can be enhanced 1.71 times as compared to that of the counterpart LED without SA. Both performance and stability of pure blue NPL LEDs can be greatly improved via ligand passivation, alternate droplet/spin coating method, and device structure optimization, which is a trend to promote the development of pure blue perovskite LEDs in future.
研究领域:
材料科学
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光学工程
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电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Dicai Zhuang,Yingyu Wang,Qiuting Cai,Lanlan Zhai,He Huang,Guanghong Yang,Yun Yang,Lijie Zhang,Chao Zou
Quasi-two-dimensional perovskite has been widely used in blue perovskite light-emitting diodes. However, the performance of these devices is still hampered by random phase distribution, nonradiative recombination, and imbalanced carrier transport. In this work, an effective strategy is proposed to mitigate these limitations by inserting lithium salts at the interfaces between the hole transport layer (HTL) and the perovskite layer. The perovskite film on the inserted Li2CO3 layer exhibits reasonable n-value redistribution, which leads to the repressive nonradiation recombination and enhanced carrier transport. Moreover, the inserted Li2CO3 layer also improves the electrical conductivity of PEDOT:PSS and hinders indium ion diffusion from the PEDOT:PSS layer to the perovskite film, which inhibits exciton quenching and nonradiative recombination loss at the HTL/perovskite interface. Taking advantage of these merits, we have successfully fabricated efficient pure-blue PeLEDs with an external quantum efficiency of 6.2% at 472 nm and a luminance of 726 cd cm–2. The restraint of nonradiative recombination at the interface offers a promising approach for efficient pure-blue PeLEDs.
研究领域:
材料科学
·
光电技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Jie Guo,Qiang Hu,Min Lu,Asu Li,Xiaoyu Zhang,Ren Sheng,Ping Chen,Yu Zhang,Jinlei Wu,Yuhao Fu,Guang Sun,William W. Yu,Xue Bai
One-dimensional (1D) semiconductor nanorods (NRs) are very promising materials for light-emitting diodes (LEDs) due to their unique optoelectronic properties, while the research on 1D perovskite NRs is relatively rare. Herein, the 1D CsCdBr 3 perovskite NRs were synthesized by simple thermal injection method, in which the [CdX 6 ] 4- octahedra sharing opposite faces can form infinite linear chains along the c axis. But their low photoluminescence quantum yields (PL QYs) limit their application in LEDs. To improve the optoelectronic properties of CsCdBr 3 NRs, the PbBr 2 is chosen as the dopant to synthesize the Pb 2+ doped CsCdBr 3 perovskite NRs. When the molar ratio of PbBr 2 :CdBr 2 is 0.25, the perovskite NRs with the PL QYs of 48% and pure-blue emission centered at 459 nm were obtained. Furthermore, the optimized NRs were used as the emissive layer to fabricate a perovskite LED that is the only one blue perovskite LED based on 1D NRs. This device shows bright pure-blue emission with good spectral stability, suggesting that the 1D perovskite NRs are good choice to achieve next-generation lighting and display.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2022
·Vol. 32
·期 44
·2207069
·
IF 19.924
Aqiang Liu,Chenghao Bi,Jianjun Tian
Solution-processed light-emitting diodes (LEDs) show great potential for low-cost fabrication of large-area display panels, but the efficient perovskite LEDs (PeLEDs) cannot be achieved by all solution process, because the perovskite emitter is easily destroyed by subsequent solution. In particular, the solution-processed PeLEDs with blue emission wavelength in 460–470 nm (pure-blue, meeting Rec. 2020 standards) still is inferior. Here, highly efficient and stable pure-blue PeLEDs are achieved by all solution process based on colloidal perovskite quantum dots and difunctional ZnO (D-ZnO) nanocrystals. The D-ZnO nanocrystals are obtained by a ligand strategy of phenethylammonium bromide, which not only repairs the perovskite surface destroyed by the solvent of the D-ZnO solution, but also enables the balanced charge injection to suppress Auger recombination. The PeLED presented pure-blue emitting at 470 nm wavelength, a maximum luminance of 11 100 cd m -2 , and external quantum efficiency of 8.7% (record efficiency for pure-blue emission). The device also showed a continuous operation half-lifetime of 35 h at luminance of 100 cd m -2 .
研究领域:
材料科学
·
光电技术
✓ 已验证
DOI
高影响因子
Materials Today Physics
·
2022
·
IF 11.021
Siqi Sun,Pei Jia,Qizhang Huang,Min Lu,Po Lu,Feisong Qin,Guang Sun,Yanbo Gao,Xue Bai,Zhennan Wu,Yu Zhang
Despite rapid development of perovskite nanocrystal (PeNC) light-emitting diodes (LEDs), it remains challenging to achieve efficient and stable blue PeLEDs , especially for pure-blue PeLEDs required for displays. Mixed halide CsPb(Br/Cl) 3 NC is a common strategy to achieve pure-blue emission, but suffers from low photoluminescence quantum yield (PLQY) and spectra instability. Here, a facile approach for the synthesis of high-quality pure-blue emitting CsPb(Br/Cl) 3 NCs is reported by introducing an organic sulfonate, phenyl trifluoromethanesulfonate (PTFMS), which works as an efficient surface passivator. As a result, the optimized PeNCs achieve a high PLQY of 85% and enhanced conductivity. Furthermore, the LED based on the optimized PeNCs is developed with pure-blue emission at 469 nm, which yields an external quantum efficiency (EQE) of 1.20% and luminance of 355 cd m −2 . More impressively, the device shows excellent spectra and operation stability under voltage bias , resulting from the suppressed ion migration channels by efficient defect passivation .
研究领域:
材料科学
·
光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Yingyi Nong,Jisong Yao,Jizhong Song
The mixed-halide CsPbCl 3-x Br x perovskite quantum dots (QDs) have emerged as promising candidates for pure-blue light-emitting diodes (LEDs). However, the widely existing defects in these mixed-halide perovskites, arising from uncontrollable crystallization and low Cl vacancy formation energy, significantly restrict the device performance. Herein, a cation-anion pair-assisted synthesis strategy is proposed to obtain high-quality CsPbCl 3-x Br x QDs. Guanidinium sulfate (GA 2 SO 4 ) is introduced during the synthesis process, in which sulfate anions passivate undercoordinated Pb 2+ defects, effectively reducing the non-radiative recombination, and the guanidinium cations interact with halides on the QD surface via hydrogen bonds, inhibiting the formation of Cl vacancy defects. Benefiting from this synergistic passivation effect of the cation-anion pair, the photoluminescence quantum yield of the QDs increases from 42% to 86%. Meanwhile, the QDs exhibit high crystalline quality, which facilitates the transport of charge carriers. Resultantly, the QLEDs achieve a record external quantum efficiency of 24.9% at 470 nm, showing a 1.6-fold improvement over that of the control devices. This work demonstrates that a synergistic ion-pair passivation strategy is a practical design approach for realizing efficient and stable pure-blue perovskite LEDs.
研究领域:
材料科学
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纳米技术
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半导体器件
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光电子学
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凝聚态物理
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Jiaqing Fang,Hanlin Jia,Guangmei Zhai,Jiahao Chen,Shilong Liu,Song Cao,Yang Xu,Chunyan Yu,Yaling Wang,Wei Jia,Bingshe Xu
Colloidal quantum dots (QDs) usually surfer from incomplete ligand coverage due to the steric hinderance of bulky long-chain ligands used in the synthesis stage and ligand desorption during the purification process. In this work, a metal halide ligand-assisted purification (LAP) method is developed for the first time and applied to enhance the luminescence performance of eco-friendly ZnSeTe-based pure-blue QDs synthesized without HF. Compared to the traditional purification (TP) method, the LAP approach is capable of enhancing the photoluminescence quantum efficiency (PLQY) and environmental stability of the QDs without compromising their colloidal stability and solution processability for uniform thin-film fabrication. Among the three zinc halide ligands (ZnCl 2 , ZnBr 2 , and ZnI 2 ), ZnCl 2 -assisted purification achieved the most significant photoluminescence enhancement, increasing the QDs’ PLQY from 57% (obtained through TP) to 82%. This improvement is attributed to the fact that the small-sized chloride ligands effectively passivate QD surface defects via binding to undercoordinated surface atoms during purification. The pure-blue light-emitting diode based on the optimal LAP-QDs displayed a 4-fold increase in maximum luminescence intensity and a 1.5-fold enhancement in peak external quantum efficiency compared to that based on the TP-QDs. This study demonstrates a simple yet efficient purification strategy for improving colloidal QD luminescence.
研究领域:
材料科学
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纳米科技
·
半导体物理
·
光电子学
·
胶体化学
·
发光二极管
·
环境友好材料
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Bufan Yu,Xingxing Duan,Zhaohui Xing,Jiacheng Liu,Yutong Pan,Lei Wang,Jiangshan Chen,Dongge Ma
Quasi-2D perovskites are emerging as promising materials for light-emitting applications due to their pronounced quantum confinement effects. Blue perovskite light-emitting diodes (PeLEDs) remain fundamentally challenging yet critically demanded for display applications. Current strategies employing quasi-2D perovskites face inherent trade-offs: 1) increased spacer cation content enhances quantum confinement for blueshift but deteriorates charge transport through insulating organic layers; 2) multiphase quantum well formation broadens emission spectra (fwhm >25 nm), compromising color purity; 3) chloride incorporation for bandgap widening induces deep-level traps and accelerates halide segregation under operational voltage. Herein, we address these intertwined challenges through multifunctional additive engineering using phenylbiguanide (PBG). The conjugated molecular structure with dual −NH2/═NH groups enables 3-fold functionality: First, strong Pb–PBG coordination effectively passivates uncoordinated halide vacancies, suppressing nonradiative recombination and achieving a high photoluminescence quantum yield (PLQY) of 76.6%. Second, hydrogen-bonding networks between PBG and [PbX6]4– frameworks immobilize halide ions, inhibiting electric-field-driven Cl/Br phase segregation. Third, PBG modulates crystallization kinetics to produce a narrow quantum well distribution for narrow emission (fwhm = 21 nm) at 472 nm and efficient Förster resonance energy transfer. The synergistic effects yield pure-blue PeLEDs with an impressive EQE of 9.32% at 472 nm, with stable emission and a 10-fold enhancement of lifetime compared to the pristine device without PBG. This work offers a promising approach to the development of high-performance blue PeLEDs using quasi-2D perovskites.
研究领域:
材料科学
·
光电子学
·
半导体器件
·
发光二极管
·
钙钛矿材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）