Materials, Structures, and Strategies for Foldable Electroluminescent Devices

Abstract

Foldable electroluminescent (EL) devices have attracted much attention in recent years. By folding, 2D EL devices can be transformed to 3D structures, which play an important role in foldable, portable, and 3D displays. Foldability is similar to flexibility, but there are differences. Foldable electronic devices mainly focus on the properties of the folding regions, which are flexible or stretchable, while the non‐folding regions may be rigid. On the other hand, folding deformation is usually accompanied by severe and sharp compression and stretching in the folding regions, which have a significant impact on device performance. The unique deformation characteristics make foldable devices complicated in materials, structures, and strategies. In this review, the progress of foldable electronic devices is summarized. According to the crease characteristics, foldable devices are divided into a free‐folding type and a crease‐preset type. First, the materials, structures, and strategies of various non‐luminescent foldable electronic devices are summarized, which will enlighten the research of foldable EL devices. Then, the progress of foldable EL devices is summarized. Foldable EL devices are still in the early stage of research and still face many problems and challenges. It is hoped that this review can promote their rapid development.

Structural and Material-Based Approaches for the Fabrication of Stretchable Light-Emitting Diodes

“…Recently, design strategies inspired by paper artwork, named kirigami and origami, have been extensively applied to a wide range of electronics, encompassing antennas [ 78 ], image sensors [ 79 , 80 ], battery [ 81 , 82 ], and bioelectronics [ 83 , 84 ]. A kirigami-based structure involves cutting the edges or central parts of devices [ 85 , 86 ], while an origami-based structure involves the controlled folding of devices into desired patterns [ 87 , 88 , 89 ]. When applied to stretchable LEDs, kirgami and origami-inspired structures can provide a reliable route for transforming the 2D plane-wise LED structures into various 3D forms under the applied external forces [ 90 , 91 , 92 ].…”

Enhanced LED Performance by Ion Migration in Multiple Quantum Well Perovskite

“…In recent years, the LED field has attracted much attention due to the discovery and development of new electroluminescent materials. These new materials aim to reduce manufacturing costs, improve color purity, and open new possibilities such as manufacturing flexible devices which show a great promise in organic LED (OLED), light emitting electrochemical cells (LEC), and perovskite based light emitting diodes (PeLEDs). , These devices share a similar architecture based on an electroluminescent material layer. Understanding the mechanism of these devices is an important step toward their commercialization.…”