한승봉 교수

A transparent heater is produced from single-walled carbon nanotubes (SWCNTs) with a high thermal conductivity. A transparent conducting SWCNT film is fabricated on glass or polymer substrates by using a vacuum infiltration method. SWCNT films with a transparency of 65–97 % and a sheet resistance of 230–3500 Ω square–1 are demonstated. These films are good candidates for many applications that require transparent film heaters.

Highly efficient human skin systems transmit fast adaptive (FA) and slow adaptive (SA) pulses selectively or consolidatively to the brain for a variety of external stimuli. The integrated analysis of these signals determines how humans perceive external physical stimuli. Here, a self-powered mechanoreceptor sensor based on an artificial ion-channel system combined with a piezoelectric film is presented, which can simultaneously implement FA and SA pulses like human skin. This device detects stim

The irreversible photoenhancement of a quantum dot (QD) nanocomposite is demonstrated using UV photo-annealing. The QD nanocomposite consists of a mixture of thermally curable polymer and a QD, which is synthesized as a core/multishell nanocrystal, CdSe/CdS/CdZnS/ZnS. Exposure under 365-nm UV illumination for 30 min at 70 W surprisingly reveals that the photoluminescence of the QD nanocomposite increases 1.8 times.

The human cutaneous sensory organ is a highly evolved biosensor that is efficient, sensitive, selective, and adaptable. Recently, with the development of various materials and structures inspired by sensory organs, artificial cutaneous sensors have been widely studied. In this study, the acquisition of biophysical signals is demonstrated at one point on the body using a wearable all-gel-integrated multimodal sensor composed of four element sensors, inspired by the slow/rapid adapting functions o

We report successive and large-scale synthesis of InP/ZnS core/shell nanocrystal quantum dots (QDs) using a customized hybrid flow reactor, which is based on serial combination of a batch-type mixer and a flow-type furnace. InP cores and InP/ZnS core/shell QDs were successively synthesized in the hybrid reactor in a simple one-step process. In this reactor, the flow rate of the solutions was typically 1 ml min(-1), 100 times larger than that of conventional microfluidic reactors. In order to syn

The direct transfer method of large area monolayer CVD graphene from Cu foil to various substrates such as PET, PDMS, and glass is developed using mechano-electro-thermal forces based on ultraconformal contact without any metal etching process or additional carrier layers in a solid-state process. Transferred graphene presents both excellent quality (with no residues, few defects, or no folding) and remarkable mechanical and electrical stability.

Recently, wearable triboelectric sensors capable of self-powering, which can be widely used in artificial skin and robotics, have received much attention. Herein, we develop a stretchable triboelectric pressure sensor with a new pattern by superimposing two patterns using both polystyrene beads and UV-ozone treatment. This patterned structure works more sensitively to pressure than a general planar and one-kind patterned structure. The sensor is constructed by sandwiching styrene butadiene rubbe

Novel hydrogel shows highly elastic, conductive, tough, transparent, humidity-resistive property which is useful for the wearable strain-sensing device.

We report a graphene oxide/cross-linking agent (GO/CA) composite inspired by the nacre structure. Based on the "brick-and-mortar" concept of nacre, graphene oxide and a cross-linking agent are covalently conjugated in the form of nacre. The mechanical characteristics of the nacre-mimetic GO/CA composite film can be controlled by adjusting the preparation method, degree of cross-linking, and cross-linking times. As a result, the cross-linking strategy can drastically enhance the tensile strength

Fabricating stretchable conductors through simple, cost-effective and scalable methods is a challenge. Here, we report on an approach used to develop nanowelded Ag nanowire/single-walled carbon nanotube (AgNW/SWCNT) hybrid films to be used as high-performance stretchable conductors. Plasmonic welding, which was done at the junctions of AgNWs in order to form hybrid AgNW/SWCNT conductors on an Ecoflex substrate, enabled excellent electrical and mechanical stability under large tensile strains of