Highly Flexible CsPbI₃ Perovskite Nanocrystal Light‐Emitting Diodes

Abstract

The superior optical and electrical properties of perovskite nanocrystals (NCs) make them attractive for light‐emitting diodes (LEDs). However, making stable flexible LEDs still remains a big challenge. Here, highly flexible CsPbI3 perovskite LEDs were fabricated using a photopolymer as the substrate, and an ultra‐smooth Ag films instead of ITO as the bottom electrode. Moreover, the device electron injection was also improved with Ag electrode. The flexible LEDs exhibited excellent electroluminescence characteristics with a low turn‐on voltage of 2.0 V and an external quantum efficiency of 8.2%. In addition, the flexible LEDs maintained their good performance after 1000 times of repeated 180 degree stretch‐release bending.

Ligand & band gap engineering: tailoring the protocol synthesis for achieving high-quality CsPbI3 quantum dots

“…QDs LEDs (EQE = 5.92 %, VON = 9.2 V), 30 KBr-passivated CsPbBr3-xIx QDs LEDs (EQE = 3.55 %, VON = 4.6), 64 and relatively close to the performance of highly flexible CsPbI3 QDs LEDs (EQE = 8.2 %, VON = 2 V). 65 Furthermore, the CsPbI3 LEDs fabricated in this study corresponds to a deep red color that have the CIE chromaticity coordinates (x,y), beyond the red emission coordinates according with the Rec. 2020 standards for red color (0.708, 0.292), 39 see Figure 5g,h and Table S4.…”

Ion Migration: A “Double‐Edged Sword” for Halide‐Perovskite‐Based Electronic Devices

“…Recently, inorganic perovskite materials such as CsPbI 3 , CsPbI 2 Br, and CsPb x Sn 1− x I 3 have been widely explored for solar cells, LEDs, photodetectors, and RS memory devices . Compared with HOIPs, the thermal stability of inorganic perovskite materials is greatly improved, greatly advantage toward real applications.…”

Charge transfer between lead halide perovskite nanocrystals and single-walled carbon nanotubes

“…Metal halide perovskites 1 have emerged among the superior materials for optoelectronic devices [2][3][4] including light-emitting diodes, 4 solar cells, 5,6 photodetectors, lasers, and in light harvesting. 2,3,[8][9][10][11][12] The efficacy of these applications relies on good absorption characteristics, easy charge carrier formation and transport in these materials. 2,[13][14][15] Besides, the low-cost solution synthesis of these perovskite nanocrystals (PNCs) results in intense uorescence and nearly unity quantum yield.…”