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钙钛矿材料因其可调带隙和高荧光效率成为发光二极管（LED）的研究热点，但混合卤素（Br-/Cl-）体系的相分离问题严重制约蓝光LED的稳定性。本文提出通过调控前驱体中铯铅含量比，形成CsPb (Br1-xClx)3/Cs4Pb (Br1-xClx)6复合相结构。结果表明Cs4Pb (Br1-xClx)6相的纳米晶颗粒聚集并包复在CsPb (Br1-xClx)3大晶粒周围，物理上阻隔了卤素离子的迁移，避免了相分离的产生。宽带隙的Cs4Pb (Br1-xClx)6还引入了量子限域效应，钝化表面缺陷态，提升CsPb (Br1-xClx)3材料光电性能。优化后的器件在50 mA/cm2电流密度下光谱稳定性显著提升。该研究为高稳定性蓝光钙钛矿LED提供了新思路。This study tackles the significant challenge of phase separation in mixed halide (Br-/Cl-) perovskite systems, which severely impacts the spectral stability of blue perovskite light-emitting diodes (PeLEDs). A compositional engineering strategy is proposed, precisely controlling the Cs:Pb molar ratio (1:1 to 1.1:1) in precursor solutions to construct a CsPb(Br1-xClx)3/Cs4Pb(Br1-xClx)6 composite phase structure. TEM mapping and XRD analysis confirm the in situ growth of Cs4Pb(Br1-xClx)6 nanocrystals (5-8 nm in diameter) uniformly encapsulating CsPb(Br1-xClx)3 microparticles (50-100 nm). This composite architecture offers dual functional benefits: 1. the Cs4PbX6 shell acts as a physical barrier, reducing halide ion migration activation energy and suppressing phase segregation during continuous operation. 2. the wide-bandgap (3.9-4.3 eV) Cs4PbX6 induces quantum confinement effects, confining carriers within CsPbX3 while passivating defect states, thereby enhancing perovskite performance. The optimized PeLED achieves notable improvements in brightness, external quantum efficiency, and operational stability, maintaining stable emission at 478 nm under a 50 mA/cm2 current density. This is achieved through suppressed halide phase separation and enhanced carrier recombination efficiency enabled by the cesium lead halide heterojunction system. This work provides fundamental insights into phase-stable perovskite design via composite crystallization kinetics, offering a viable pathway toward commercial-grade blue PeLEDs for full-color displays.
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Keywords:
- Perovskite /
- Blue Light /
- Light-Emitting Diode (LED)
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[1] Stranks S D, Eperon G E, Grancini G, Menelaou C, Alcocer M, Leijtens T, Herz L M, Petrozza A, Snaith H J 2013 Science 342 341
[2] deQuilettes D W, Koch S, Burke S, Paranji R K, Shropshire A J, Ziffer M E, Ginger D S 2016 ACS Energy Lett. 1 438
[3] Steirer K X, Schulz P, Teeter G, Stevanovic V, Yang M, Zhu K, Berry J J 2016 ACS Energy Lett. 1 360
[4] Tan Z K, Moghaddam R S, Lai M L, Docampo P, Higler R, Deschler F, Price M, Sadhanala A, Pazos L M, Credgington D, Hanusch F, Bein T, Snaith H J, Friend R H 2014 Nature Nanotech 9 687
[5] Batignani G, Fumero G, Kandada A R S, Cerullo G, Gandini M, Ferrante C, Petrozza A, Scopigno T 2018 Nat. Commun. 9 1971
[6] Ivanovska T, Dionigi C, Mosconi E, De Angelis F, Liscio F, Morandi V, Ruani G 2017 J. Phys. Chem. Lett. 8 3081
[7] Feng S C, Shen Y, Hu X M, Su Z H, Zhang K, Wang B F, Cao L X, Xie F M, Li H Z, Gao X, Tang J X, Li Y Q 2024 Adv. Mater. 36 2410225
[8] Xing Z, Jin G, Du Q, Pang P, Liu T, Shen Y, Zhang D, Yu B, Liang Y, Yang D, Tang J, Wang L, Xing G, Chen J, Ma D 2024 Adv. Mater. 36 2406706
[9] Gao Y, Cai Q, He Y, Zhang D, Cao Q, Zhu M, Ma Z, Zhao B, He H, Di D, Ye Z, Dai X 2024 Sci. Adv. 10 eado5645
[10] Jiang Y, Sun C, Xu J, Li S, Cui M, Fu X, Liu Y, Liu Y, Wan H, Wei K, Zhou T, Zhang W, Yang Y, Yang J, Qin C, Gao S, Pan J, Liu Y, Hoogland S, Sargent E H, Chen J, Yuan M 2022 Nature 612 679
[11] Guo B, Lai R, Jiang S, Zhou L, Ren Z, Lian Y, Li P, Cao X, Xing S, Wang Y, Li W, Zou C, Chen M, Hong Z, Li C, Zhao B, Di D 2022 Nat. Photon. 16 637
[12] Kim J S, Heo J M, Park G S, Woo S J, Cho C, Yun H J, Kim D H, Park J, Lee S C, Park S H, Yoon E, Greenham N C, Lee T W 2022 Nature 611 688
[13] Jiang Y, Qin C, Cui M, He T, Liu K, Huang Y, Luo M, Zhang L, Xu H, Li S, Wei J, Liu Z, Wang H, Kim G H, Yuan M, Chen J 2019 Nat. Commun. 10 1868
[14] Chu Z, Zhao Y, Ma F, Zhang C X, Deng H, Gao F, Ye Q, Meng J, Yin Z, Zhang X, You J 2020 Nat. Commun. 11 4165
[15] Li Z, Chen Z, Yang Y, Xue Q, Yip H L, Cao Y 2019 Nat. Commun. 10 1027
[16] Xing J, Zhao Y, Askerka M, Quan L N, Gong X, Zhao W, Zhao J, Tan H, Long G, Gao L, Yang Z, Voznyy O, Tang J, Lu Z H, Xiong Q, Sargent E H 2018 Nat. Commun. 9 3541
[17] Li Z, Chen Z, Shi Z, Zou G, Chu L, Chen X K, Zhang C, So S K, Yip H L 2023 Nat. Commun. 14 6441
[18] Karlsson M, Yi Z, Reichert S, Luo X, Lin W, Zhang Z, Bao C, Zhang R, Bai S, Zheng G, Teng P, Duan L, Lu Y, Zheng K, Pullerits T, Deibel C, Xu W, Friend R, Gao F 2021 Nat. Commun. 12 361
[19] Bischak C G, Hetherington C L, Wu H, Aloni S, Ogletree D F, Limmer D T, Ginsberg N S 2017 Nano Lett. 17 1028
[20] Brennan M C, Draguta S, Kamat P V, Kuno M 2018 ACS Energy Lett. 3 204
[21] Xing J, Zhao Y, Askerka M, Quan L N, Gong X, Zhao W, Zhao J, Tan H, Long G, Gao L, Yang Z, Voznyy O, Tang J, Lu Z-H, Xiong Q, Sargent E H 2018 Nat. Commun. 9 3541
[22] Wang X, Ling Y, Lian X, Xin Y, Dhungana K B, Perez O F, Knox J, Chen Z, Zhou Y, Beery D, Hanson K, Shi J, Lin S, Gao H 2019 Nat. Commun. 10 695
[23] Wang L, Liu H, Zhang Y, Mohammed O F 2020 ACS Energy Lett. 5 87
[24] Du P, Li J, Wang L, Sun L, Wang X, Xu X, Yang L, Pang J, Liang W, Luo J, Ma Y, Tang J 2021 Nat. Commun. 12 4751
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