Enhanced performance of spectra stable blue perovskite light-emitting diodes through Poly(9-vinylcarbazole) interlayer incorporation

• Published in: Organic electronics 2021-09, Vol.96, p.106259, Article 106259
• Main Authors: Wu, Yanyan, Yuan, Fang, Fu, Feifei, Liu, Chenxing, Jiao, Bo, Zhang, Fanghui, Wu, Zhaoxin
• Format: Article
• Language: English
• Subjects: High stability; Interface modification; Light-emitting diode; Perovskite
• ISSN: 1566-1199; 1878-5530
• DOI: 10.1016/j.orgel.2021.106259

Since the emergence of organic-inorganic hybrid perovskites, the development of perovskite light-emitting diodes (PeLEDs) with green/red emission have made great progress, and the corresponding external quantum efficiency (EQE) has exceeded 20%. However, the research progress of blue-emitting PeLED still has certain challenges. In this article, a multi-cation per-bromine perovskite film is prepared by introducing polymer molecules poly(9-vinylcarbazole) (PVK) in an anti-solvent (chloroform). When the concentration of PVK is optimized to 0.1 mg/mL, a smooth, dense, high-quality film with photoluminescence quantum efficiency (PLQY) up to 20.70% is obtained. The introduction of PVK can assist the formation of perovskite films for interface modification via surface defect passivation. The optimized blue PeLED has a maximum brightness of 3136 cd/m2 and a maximum EQE of 3.49% at 488 nm. More importantly, the optimized blue PeLED has excellent color stability under high applied voltage up to 12 V or continuous operation. [Display omitted] •A per-bromine perovskite film is prepared by introducing polymer molecules poly(9-vinylcarbazole) in chloroform.•The PVK can assist the formation of perovskite films for interface modification via surface defect passivation.•The optimized blue PeLED has excellent color stability under high applied voltage up to 12 V or continuous operation.