Modulating low-dimensional domains of self-assembling quasi-2D perovskites for efficient and spectra-stable blue light-emitting diodes

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2021-07, Vol.415, p.129088, Article 129088
• Main Authors: Tian, Yu, Qian, Xiao-Yan, Qin, Chao-Chao, Cui, Ming-Huan, Li, Yan-Qing, Ye, Yong-Chun, Wang, Jing-Kun, Wang, Wen-Jun, Tang, Jian-Xin
• Format: Article
• Language: English
• Subjects: Blue emission; Low-dimensional domains; Perovskite light-emitting diode; Self-assembling construction
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2021.129088

[Display omitted] •The DETA additive is used for domain regulation and radiative recombination.•The layer numbers of metal halide octahedron PbBr64− can be precisely adjusted.•The emission of pure-bromide perovskites is tuned from violet to greenish-blue.•Efficient blue perovskite light-emitting diodes are achieved.•The EQEs are 1.74%, 2.44% and 5.71% for deep-, pure- and sky-blue emissions. Perovskite light-emitting diodes (PeLEDs) with green and red emissions have made tremendous progress in recent years. However, the realization of efficient and spectra-stable blue-emission PeLEDs remains challenging, which greatly limits their future commercialization. Here, a self-assembling strategy is proposed to achieve efficient blue PeLEDs with stable emission by modulating low-dimensional domains of pure-bromide perovskites to Bohr’s radii. A spacer of butylamine with polyamine is used as a modifier to facilitate the formation of homogeneous perovskite films with precious tailoring of the numbers (N) of metal halide octahedron PbBr64− layers. The cubic-phase quasi-2D perovskite films featuring the improved domain distributions and the enhanced luminance are realized, and their emissions can be modulated from violet (~436 nm) to greenish region (~500 nm), corresponding to the emission from N = 2 to N > 3 layered perovskites. The PeLEDs with deep-blue, pure-blue, and sky-blue emissions are obtained with the colour coordinates of (0.13, 0.06), (0.11, 0.13), and (0.08, 0.25), respectively, yielding the maximum external quantum efficiencies of 1.74%, 2.44%, and 5.71%. The approach demonstrated in this work paves the way for constructing efficient, endurable, spectra-stable perovskite emitters for the next-generation display and lighting technologies.