A5023297818- Advanced Sensor and Energy Harvesting Materials
- Advanced Materials and Mechanics
- Nanomaterials and Printing Technologies
- Tactile and Sensory Interactions
- Conducting polymers and applications
- Dielectric materials and actuators
- Micro and Nano Robotics
- Modular Robots and Swarm Intelligence
- Organic Light-Emitting Diodes Research
- Hydrogels: synthesis, properties, applications
- 3D Printing in Biomedical Research
- Supercapacitor Materials and Fabrication
- Nanowire Synthesis and Applications
- Gold and Silver Nanoparticles Synthesis and Applications
- Neuroscience and Neural Engineering
- EEG and Brain-Computer Interfaces
- Semiconductor materials and devices
- Soft Robotics and Applications
- Random lasers and scattering media
- Polydiacetylene-based materials and applications
- Polymer composites and self-healing
- Thermal properties of materials
- Advanced Chemical Sensor Technologies
- Microfluidic and Capillary Electrophoresis Applications
- Photochromic and Fluorescence Chemistry
Carnegie Mellon University
2020-2024
Seoul National University
2016-2022
Government of the Republic of Korea
2016-2018
University of Illinois Urbana-Champaign
2015-2017
A soft, skin-mounted microfluidic device captures microliter volumes of sweat and quantitatively measures biochemical markers by colorimetric analysis.
Significance Conventional electroencephalogram (EEG) recording systems, particularly the hardware components that form physical interfaces to head, have inherent drawbacks limit widespread use of continuous EEG measurements for medical diagnostics, sleep monitoring, and cognitive control. Here we introduce soft electronic constructs designed intimately conform complex surface topology auricle mastoid, provide long-term, high-fidelity data. Systematic studies reveal key aspects extreme levels...
Recent research progress of relieving discomfort between electronics and human body involves serpentine designs, ultrathin films, extraordinary properties nanomaterials. However, these strategies addressed thus far each face own limitation for achieving desired form electronic-skin applications. Evenly matched mechanical anywhere on the imperceptibility are two essentially required characteristics future (E-skin) devices. Yet accomplishing main simultaneously is still very challenging....
Future electronics are expected to develop into wearable forms, and an adequate stretchability is required for the forthcoming considering various motions occurring in human body. Along with stretchability, transparency can increase both functionality esthetic features future electronics. In this study, we demonstrate, first time, a highly stretchable transparent electromagnetic interference shielding layer electronic applications silver nanowire percolation network on elastic...
Abstract To add more functionalities and overcome the limitation in conventional soft robots, highly anisotropic actuators with color shifting function during actuation is demonstrated for first time. The electrothermally operating installed transparent metal nanowire percolation network heater allow easy programming of their direction instantaneous visualization temperature changes through change. Due to unique dependent coefficient thermal expansion mismatch, suggested actuator...
Abstract State monitoring of the complex system needs a large number sensors. Especially, studies in soft electronics aim to attain complete measurement body, mapping various stimulations like temperature, electrophysiological signals, and mechanical strains. However, conventional approach requires many sensor networks that cover entire curvilinear surfaces target area. We introduce new measuring system, novel electronic skin integrated with deep neural network captures dynamic motions from...
Air quality has become a major public health issue in Asia including China, Korea, and India. Particulate matters are the concern air quality. We present first environmental application demonstration of Ag nanowire percolation network for novel, electrical type transparent, reusable, active PM2.5 filter although been studied as very promising transparent conductor optoelectronics. Compared with previous particulate matter study using relatively weaker short-range intermolecular force polar...
Well dispersed very long and thin silver nanowires are synthesized using glucose as a reducing agent chloride source. The wire lengths in the range of 200 to 500 microns with an average diameter 45–65 nm.
Abstract Development of an artificial camouflage at a complete device level remains vastly challenging task, especially under the aim achieving more advanced and natural characteristics via high-resolution patterns. Our strategy is to integrate thermochromic liquid crystal layer with vertically stacked, patterned silver nanowire heaters in multilayer structure overcome limitations conventional lateral pixelated scheme through superposition heater-induced temperature profiles. At same time,...
Abstract Kirigami, a traditional paper‐cutting art, is promising method for creating mechanically robust circuitry unconventional devices capable of extreme stretchability through structural deformation. In this study, design approach expanded upon by introducing Liquid Metal based Elastic Kirigami Electrodes (LM‐eKE) in which kirigami‐patterned soft elastomers are coated with eutectic gallium‐indium (EGaIn) alloy. Overcoming the mechanical and electrical limitations previous efforts...
Significance Existing options for electrical power generation and storage in wearable electronics are incompatible with thin geometries, soft, stretchable mechanics, lightweight construction needed long‐lived, intimate interfaces the skin. Here we demonstrate concepts that allow integration of collections thin, millimeter-scale solid-state batteries multijunction solar cells into electrically interconnected arrays simultaneously provide high-performance operation biocompatible mechanics at...
Although solution processed metal nanowire (NW) percolation networks are a strong candidate to replace commercial indium tin oxide, their performance is limited in thin film device applications due reduced effective electrical areas arising from the dimple structure and percolative voids that single size NW inevitably possess. Here, we present transparent electrode based on dual-scale silver (AgNW) network embedded flexible substrate demonstrate significant enhancement area by filling large...
Liquid metal embedded elastomers (LMEEs) are composed of a soft polymer matrix with droplets alloys that liquid at room temperature. These matter composites exhibit exceptional combinations elastic, electrical, and thermal properties make them uniquely suited for applications in flexible electronics, robotics, management. However, the fabrication LMEE structures has primarily relied on rudimentary techniques limit patterning to simple planar geometries. Here, we introduce an approach direct...
Abstract Stretchable electronics is playing an integral role in fields such as wearable and soft robots. Among conductive materials, liquid metal drawing intense attention electrode material due to its nature at room temperature. However, the merits of conductor are limited by presence substrates or enclosed microchannels from physical disturbances underlying substrate when applying it 3D surface modifying complex circuit. To overcome this limitation, we develop freestanding patterned...
Owing to its low mechanical compliance, liquid metal is intrinsically suitable for stretchable electronics and future wearable devices. However, invariable strain-resistance behavior according the strain-induced geometrical deformation difficulty of circuit patterning limit extensive use metal, especially strain-insensitive wiring purposes. To overcome these limitations, herein, novel liquid-metal-based electrodes fragmented eutectic gallium-indium alloy (EGaIn) Ag nanowire (NW) backbone...
Due to emerging demands in soft electronics, there is an increasing need for material architectures that support robust interfacing between substrates, stretchable electrical interconnects, and embedded rigid microelectronics chips. Though researchers have adopted rigid-island structures solve the issue, this approach merely shifts stress concentrations from chip-conductor interfaces rigid-island-soft region substrate. Here, a gradient stiffness-programmed circuit board (GS-PCB) possesses...
Since transparent conducting films based on silver nanowires (AgNWs) have shown higher transmittance and electrical conductivity compared to those of indium tin oxide (ITO) films, the electronics industry has recognized them as promising substitutes. However, due haze value AgNW ITO clarity is decreased when are applied optoelectronic devices. In this study, we develop a highly transparent, low-haze, very long percolation network. Moreover, confirm that analyzed chemical roles can easily be...
Bundled metal nanowire network transparent conductor with enhanced mechanical characteristics was fabricated from random crack patterns.
Transparency in electronics can provide extra functionality and esthetic impression. plays an important role accurate soft robot control because one directly observe target surface condition that is usually blocked by a robot's body. Nowadays, demand for actuators has been rapidly increasing robots have attracted much attention recently. However, conventional are nontransparent with simple isotropic bending, limited performance, functionality. To overcome such limitations of current robots,...