KES5-0888
Flexible/Stretchable Light-Emitting Devices for Intelligent Wearable Electronics
When and Where
Sep 30, 2026
16:25 - 16:50
Presenter(s)
Tae-Woo Lee (Seoul National University)
Co-Author(s)
Abstract
Flexible and stretchable light-emitting devices are emerging as key components of wearable electronics, enabling mechanically compliant platforms that can sense, display, and process information. Here, we present advances in light-emitting devices for wearable systems, focusing on high-efficiency fully stretchable OLEDs and neuromorphic light-emitting transistors that combine low-voltage light emission with signal processing and memory.
The efficiency limitations of fully stretchable OLEDs arise from poor charge injection from stretchable electrodes and inefficient exciton utilization in stretchable emitters. Herein, we developed 2D-contact stretchable electrodes, in which graphene or MXene on silver nanowire networks enhances charge spreading and enables work function tuning. In addition, we introduced an exciplex-assisted phosphorescent layer (ExciPh) to overcome suppressed exciton energy transfer in emitters caused by insulating elastomers. ExciPh enables elastomer-tolerant triplet recycling, allowing triplet excitons to be efficiently harvested through Förster resonance energy transfer. Combining ExciPh with 2D-contact stretchable electrodes yielded fully stretchable OLEDs with a record efficiency of 17.0%.
We also introduce a single-active-layer electrochemical organic light-emitting transistor as a neuromorphic optoelectronic platform. An ion-transport enhancer in the emissive polymer channel forms a drain-side electric double layer, facilitating charge injection, enabling light emission below 3.5 V, and producing a broad, spatially confined recombination zone. The device exhibits a recombination zone width of 267 μm and a maximum luminance of 826 cd m⁻² at 3.5 V. Flexible, large-area devices powered by two 1.50 V batteries demonstrate their potential for stand-alone wearable systems.
Together, these advances suggest a path toward mechanically compliant wearable optoelectronic platforms that can visualize, process, and respond to information.
The efficiency limitations of fully stretchable OLEDs arise from poor charge injection from stretchable electrodes and inefficient exciton utilization in stretchable emitters. Herein, we developed 2D-contact stretchable electrodes, in which graphene or MXene on silver nanowire networks enhances charge spreading and enables work function tuning. In addition, we introduced an exciplex-assisted phosphorescent layer (ExciPh) to overcome suppressed exciton energy transfer in emitters caused by insulating elastomers. ExciPh enables elastomer-tolerant triplet recycling, allowing triplet excitons to be efficiently harvested through Förster resonance energy transfer. Combining ExciPh with 2D-contact stretchable electrodes yielded fully stretchable OLEDs with a record efficiency of 17.0%.
We also introduce a single-active-layer electrochemical organic light-emitting transistor as a neuromorphic optoelectronic platform. An ion-transport enhancer in the emissive polymer channel forms a drain-side electric double layer, facilitating charge injection, enabling light emission below 3.5 V, and producing a broad, spatially confined recombination zone. The device exhibits a recombination zone width of 267 μm and a maximum luminance of 826 cd m⁻² at 3.5 V. Flexible, large-area devices powered by two 1.50 V batteries demonstrate their potential for stand-alone wearable systems.
Together, these advances suggest a path toward mechanically compliant wearable optoelectronic platforms that can visualize, process, and respond to information.
