Flexible and Stretchable Light-Emitting Diodes and Photodetectors for Human-Centric Optoelectronics

Abstract

Optoelectronic devices with unconventional form factors, such as flexible and stretchable light-emitting or photoresponsive devices, are core elements for the nextgeneration human-centric optoelectronics. For instance, these deformable devices can be utilized as closely fitted wearable sensors to acquire precise biosignals that are subsequently uploaded to the cloud for immediate examination and diagnosis, and also can be used for vision systems for human-interactive robotics. Their inception was propelled by breakthroughs in novel optoelectronic material technologies and device blueprinting methodologies, endowing flexibility and mechanical resilience to conventional rigid optoelectronic devices. This paper reviews the advancements in such soft optoelectronic device technologies, honing in on various materials, manufacturing techniques, and device design strategies. We will first highlight the general approaches for flexible and stretchable device fabrication, including the appropriate material selection for the substrate, electrodes, and insulation layers. We will then focus on the materials for flexible and stretchable lightemitting diodes, their device integration strategies, and representative application examples. Next, we will move on to the materials for flexible and stretchable photodetectors, highlighting the state-of-the-art materials and device fabrication methods, followed by their representative application examples. At the end, a brief summary will be given, and the potential challenges for further development of functional devices will be discussed as a conclusion.

Conjugated polymers with near-infrared (NIR) optical absorption: structural design considerations and applications in organic electronics

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Dynamics of Polyalkylfluorene Conjugated Polymers: Insights from Neutron Spectroscopy and Molecular Dynamics Simulations

“…Conjugated polymer materials have received considerable attention over the last decades because they can be integrated in flexible and stretchable lightweight optoelectronic and bioelectronic devices − such as organic led emitting diodes (OLEDs), − organic solar cells (OSCs), − organic field effect transistors (OFETs), − and more recently, organic electrochemical transistors (OECTs). − These devices could be, in principle, fabricated at low cost using roll-to-roll solution processing techniques. Initially, the development of conjugated polymers has focused on engineering the π-conjugated backbone as it gives rise to the optoelectronic properties of the material with the flexible side chains, mainly alkyl side chains, being primarily used as necessary solubilizing groups.…”

Structural Dynamics of Polymer:Non-Fullerene Organic Solar Cell Blends: A Neutron Spectroscopy Perspective

“…Conjugated polymer materials have received considerable attention over the last decades because they can be integrated in flexible and stretchable light-weight optoelectronic and bioelectronic devices [1][2][3] such as organic led emitting diodes (OLEDs), [4][5][6][7] organic solar cells (OSCs), [8][9][10] organic field effect transistors (OFETs) [11][12][13][14] and more recently in organic electrochemical transistors (OECTs). [15][16][17] These devices could be in principle fabricated at low cost using roll-to-roll solution processing techniques.…”