Byeongmoon Lee

Softening of thermoelectric generators facilitates conformal contact with arbitrary-shaped heat sources, which offers an opportunity to realize self-powered wearable applications. However, existing wearable thermoelectric devices inevitably exhibit reduced thermoelectric conversion efficiency due to the parasitic heat loss in high-thermal-impedance polymer substrates and poor thermal contact arising from rigid interconnects. Here, we propose compliant thermoelectric generators with intrinsically

The ability to image pressure distribution over complex three-dimensional surfaces would significantly augment the potential applications of electronic skin. However, existing methods show poor spatial and temporal fidelity due to their limited pixel density, low sensitivity, or low conformability. Here, we report an ultraflexible and transparent electroluminescent skin that autonomously displays super-resolution images of pressure distribution in real time. The device comprises a transparent pr

Stretchable hybrid electronics (SHE) that combine high-performance rigid electronic devices with stretchable interconnects offer a facile route for accessing and processing bio-signals and human interactions. Incorporated with sensors and wireless communications, SHE achieves novel applications such as biomedical diagnosis, skin prosthetics, and robotic skin. The implementation of reliable SHE requires the comprehensive development of stretchable electrodes, bonding techniques, and strain-engine

Random networks of single-walled carbon nanotubes (SWCNTs) offer new-form-factor electronics such as transparent, flexible, and intrinsically stretchable devices. However, the long-standing trade-off between carrier mobility and on/off ratio due to the coexistence of metallic and semiconducting nanotubes has limited the performance of SWCNT-random-network-based thin-film transistors (SWCNT TFTs), hindering their practical circuit-level applications. Methods for high-purity separation between met

High-fidelity patterning of thin metal films on arbitrary soft substrates promises integrated circuits and devices that can significantly augment the morphological functionalities of freeform electronics. However, existing patterning methods that decisively rely on prefabricated rigid masks are severely incompatible with myriad surfaces. Here, we report printable, stretchable metal-vapor-desorption layers (s-MVDLs) that can enable high-fidelity patterning of thin metal films on freeform polymeri

In light field microscopy (LFM), the F-number of the micro lens array (MLA) should be matched with the image-side F-number of the objective lens to utilize full resolution of an image sensor. We propose a new F-number matching method that can be applied to multiple objective lenses by using an elastic MLA. We fabricate an elastic MLA with polydimethylsiloxane (PDMS) using a micro contact printing method and address the strain for the F-number variation. The strain response is analyzed, and the L

A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-21629-y

Single-walled carbon nanotube (SWCNT) random networks have become strong candidates for next-generation electronics due to their exceptional mechanical, electrical, and optical properties. However, metallic nanotubes in networks generally incur a trade-off between the charge carrier mobility and on/off ratio, limiting the performance of SWCNT-based devices. Therefore, various methods to increase the purity of semiconducting nanotubes in entire random networks have been reported, but this directi

We demonstrate a novel all‐ink‐jet‐printed wearable information display. A variety of key technologies including ink‐jet‐printed stretchable interconnects, direct chip‐bonding, and printable crossover for high level system integration are developed. As a conceptual demonstration, a stretchable 4‐digit 7‐segment display is implemented, and it well operates under ~15% biaxial strain.

Abstract Printing solid-state elastic conductors into self-supporting three-dimensional (3D) geometries promises the design diversity of soft electronics, enabling complex, multifunctional, and tailored human–machine interfaces. However, the difficulties in manipulating their rheological characteristics have only allowed for layerwise deposition. Here, we report omnidirectional printing of elastic conductors enabled by emulsifying elastomer composites with immiscible, nonvolatile solvents. The s