A Strategy for Architecture Design of Crystalline Perovskite Light‐Emitting Diodes with High Performance. Issue 25 (7th May 2018)

• Record Type: Journal Article
• Authors: Shi, Yifei; Wu, Wen; Dong, Hua; Li, Guangru; Xi, Kai; Divitini, Giorgio; Ran, Chenxin; Yuan, Fang; Zhang, Min; Jiao, Bo; Hou, Xun; Wu, Zhaoxin
• Is Part Of: Advanced materials. Volume 30:Issue 25(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-05-07
• Subjects: insulator–perovskite–insulator -- LED -- perovskite -- tunneling; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201800251
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: All present designs of perovskite light‐emitting diodes (PeLEDs) stem from polymer light‐emitting diodes (PLEDs) or perovskite solar cells. The optimal structure of PeLEDs can be predicted to differ from PLEDs due to the different fluorescence dynamics and crystallization between perovskite and polymer. Herein, a new design strategy and conception is introduced, "insulator–perovskite–insulator" (IPI) architecture tailored to PeLEDs. As examples of FAPbBr3 and MAPbBr3, it is experimentally shown that the IPI structure effectively induces charge carriers into perovskite crystals, blocks leakage currents via pinholes in the perovskite film, and avoids exciton quenching simultaneously. Consequently, as for FAPbBr3, a 30‐fold enhancement in the current efficiency of IPI‐structured PeLEDs compared to a control device with poly(3, 4ethylenedioxythiophene):poly(styrene sulfonate) as hole‐injection layer is achieved—from 0.64 to 20.3 cd A −1 —while the external quantum efficiency is increased from 0.174% to 5.53%. As the example of CsPbBr3, compared with the control device, both current efficiency and lifetime of IPI‐structured PeLEDs are improved from 1.42 and 4 h to 9.86 cd A −1 and 96 h. This IPI architecture represents a novel strategy for the design of light‐emitting didoes based on various perovskites with high efficiencies and stabilities. Abstract : A concept and new architecture tailored to PeLEDs is demonstrated for the first time: "insulator–perovskite–insulator (IPI)", a pair of ultrathin insulator layers (LiF) sandwiching a perovskite film. Compared with conventional PeLEDs with a traditional holeinjection layer, a 30–40‐fold enhancement in current efficiency (CE) of IPI‐structured PeLEDs based on FA(MA)PbBr3 is achieved, with a maximum CE of 20.3 cd A −1 .