Acta Chimica Sinica ›› 2021, Vol. 79 ›› Issue (3): 223-237.DOI: 10.6023/A20100463 Previous Articles     Next Articles

Review

钙钛矿组分和结构设计及其发光二极管器件性能研究进展

郭镇域1, 周欢萍1,*()   

  1. 1 北京大学工学院 北京 100871
  • 投稿日期:2020-10-09 发布日期:2020-11-24
  • 通讯作者: 周欢萍
  • 作者简介:

    郭镇域, 北京大学工学院2018级硕士研究生, 研究方向为有机无机杂化准二维钙钛矿发光二极管器件制备.

    周欢萍, 2010年博士毕业于北京大学化学与分子工程学院. 2010年至2015年期间, 于美国加州大学洛杉矶分校材料科学与工程系从事博士后工作研究. 2015年7月加入北京大学工学院材料科学与工程系, 研究方向为新型光电半导体材料以及相关器件.

Research Progress of Composition and Structure Design in Perovskites for High Performance Light-emitting Diodes

Zhenyu Guo1, Huanping Zhou1,*()   

  1. 1 College of Engineering, Peking University, Beijing 100871, China
  • Received:2020-10-09 Published:2020-11-24
  • Contact: Huanping Zhou

Over the past few years, the external quantum efficiency (EQE) of organic-inorganic hybrid perovskite light-emitting diodes (LEDs) has experienced a tremendous progress. The reported highest EQE of infrared and green perovskite LEDs has reached 21.6% and 20.3%, respectively, which is comparable to commercial organic light-emitting diodes. Even the slightly inferior blue perovskite LEDs have a recorded EQE of 12.3%. However, poor device stability is the biggest problem hindering the commercial application of perovskite optoelectronic devices, which is a severer problem in LEDs because the higher operating voltage will trigger acute ion migration. Encouragingly, however, the lifetime of perovskite LEDs has increased from the initial several seconds to over 200 hours, presenting a dramatic progress. The outstanding performance of perovskite LEDs is closely related with the excellent material properties, including tunable bandgaps, narrow full width at half maximum (FWHM), high defect tolerance, high electron/hole mobility and solution processibility. Moreover, the diversity of components and structure of perovskite makes the addition of various additives effective, enabling optimizing device performance through kinds of chemical methods. In this review, we analyzed the impacts of component and structure designing on the efficiency and stability of perovskite LEDs from the perspective of compositional designing, defect passivation and interfacial modification. We analyzed how compositional designing affects the optoelectronic properties through altering the ratio between organic and inorganic components or adding other molecules and ions to adjust the dimension of perovskites. As for defect passivation, we discussed various passivating reagents and their working mechanism. In addition, we summarized the significance of interfacial modification between different functional layers, including improving the wetting property of the substrates, achieving higher crystal quality of perovskite films, passivating the defects at the interfaces, blocking leakage current and reducing hole/electron injecting barrier. Finally, we discussed the scientific and technological challenges yet to be resolved before perovskite LEDs can be considered for commercial applications.

Key words: perovskite, light-emitting-diodes, compositional design, defect passivation, interfacial modification