化学学报 ›› 2023, Vol. 81 ›› Issue (12): 1695-1700.DOI: 10.6023/A23070344 上一篇    下一篇

研究论文

通过聚(3,4-乙烯二氧噻吩)-聚苯乙烯磺酸改性实现高性能蓝色钙钛矿发光二极管

张璇, 熊军, 张旺*()   

  1. 深圳技术大学 新材料与新能源学院 深圳 518118
  • 投稿日期:2023-07-18 发布日期:2023-09-30

High Performance Blue Perovskite Light Emitting Diode Realized by Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) Modification

Xuan Zhang, Jun Xiong, Wang Zhang()   

  1. College of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, China
  • Received:2023-07-18 Published:2023-09-30
  • Contact: *E-mail: zhangwang@sztu.edu.cn

金属卤化物钙钛矿材料因其独特的光电特性, 在光电器件领域引起了相当大的关注和研究. 特别是近年来, 绿色和红色钙钛矿发光二极管(PeLEDs)研究取得了显著进展. 然而, 蓝色PeLEDs的发展落后于绿光和红光PeLEDs, 效率也要低得多. 其中一个主要原因是空穴传输层与蓝色钙钛矿材料的能级不匹配. 在这项研究中, 通过使用聚(4-苯乙烯磺酸钠)(PSS-Na)和溴化钾(KBr)改性空穴传输层材料聚(3,4-乙烯二氧噻吩)-聚苯乙烯磺酸(PEDOT:PSS), 抑制PEDOT:PSS与钙钛矿材料界面之间的非辐射复合. 并通过降低膜的粗糙度来提高钙钛矿膜的质量. 结果表明, PSS-Na和KBr有效地提高了空穴传输能力, 从而提高了PeLEDs器件的整体性能. 通过PSS-Na改性PEDOT:PSS制备的蓝色PeLEDs具有低启亮电压(仅为3.3 V)和高外量子效率(EQE)(达到4.12%). 随着PEDOT:PSS中进一步加入KBr, 蓝色PeLEDs最大EQE达到6.25%, 启亮电压降至3 V. 此外, 与其他蓝光钙钛矿器件相比, 该器件在不同电压下也表现出了良好的光谱稳定性. 说明通过改性空穴传输层, 可以提高钙钛矿发光器件的效率和稳定性, 显示出钙钛矿发光二极管在彩色显示器和固态照明中的潜力.

关键词: 钙钛矿材料, 蓝光PeLEDs, 空穴传输层, 改性

Metal halide perovskite materials, with their high stability and excellent optical properties, have attracted considerable attention and research in the field of optoelectronic devices. Especially in recent years, the research of green and red perovskite light-emitting diodes (PeLEDs) has made remarkable progress. However, the development of blue PeLEDs has lagged behind that of green and red PeLEDs, and is much less efficient, limiting the applications of perovskite light-emitting devices in color displays and solid-state lighting. One of the main reasons is the mismatch between the energy levels of the hole transporting layer and the blue perovskite material. In this study, we inhibited the non-radiative recombination between the interface of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) and perovskite materials by first modifying the hole transporting layer material PEDOT:PSS with poly(sodium 4-styrenesulfonate) (PSS-Na) and potassium bromide (KBr). The quality of the perovskite layer film was improved by optimizing the fabrication process to reduce the roughness of the hole transporting layer film. Finally, perovskite light emitting devices are fabricated by vacuum evaporation. It is shown that the use of PSS-Na and KBr can effectively increase the hole transporting capacity and thus improve the overall performance of the PeLEDs device. Moreover, the blue PeLEDs prepared by PEDOT:PSS modified by PSS-Na alone have low on-voltage (only 3.3 V) and high external quantum efficiency (EQE) (up to 4.12%). With the further addition of KBr to the modified PEDOT:PSS of PSS-Na, the maximum EQE of the final blue PeLEDs reaches 6.25%, the on-chip voltage drops to 3 V, and the peak wavelength is 488 nm, which is a blue sky perovskite light emitting device. In addition, compared to other blue-emitting perovskite devices, this device also exhibits excellent spectral stability at different voltages. The efficiency and stability of perovskite light-emitting devices can be improved by modifying the hole transporting layer, showing the potential of perovskite light-emitting diodes for color displays and solid-state lighting.

Key words: perovskite material, blue PeLEDs, hole transporting layer, modification