Daejoon Kang

We report a successful synthesis of copper oxide nanowires with an average diameter of 90 nm and lengths of several micrometers by using a simple and inexpensive wet chemical method. The CuO nanowires prepared via this method are advantageous for industrial applications which require mass production and low thermal budget technique. It is found that the concentration and the quantity of precursors are the critical factors for obtaining the desired one-dimensional morphology. Field emission scann

Abstract Phytohormones play critical roles in regulating plant responses to stress. Here, we investigated the effects of salt stress and stress recovery by applying jasmonate to the two different rice ( Oryza sativa L.) cultivars Dongjinchalbyeo (DJC, salt‐tolerant) and Dongjinbyeo (DJ, salt‐sensitive). Salt stress remarkably decreased the root length of plants even at low NaCl concentration (20 m m ). Salt stress led to a sharp increase in the concentrations of abscisic acid (ABA) in 20 and 40

In this work, a new approach to modifying poly(dimethylsiloxane) (PDMS) as a negative triboelectric material using graphene oxide (GO) and a sodium dodecyl sulfate (SDS) surfactant was reported. A porous PDMS@GO@SDS composite triboelectric nanogenerator (TENG) could deliver an output voltage and current of up to 438 V and 11 μA/cm², respectively. These values were 3-fold higher than those of the flat PDMS. The superior performance is attributed to the intensified negative charges on P

High-performance thermal management materials are essential in miniaturized, highly integrated, and high-power modern electronics for heat dissipation. In this context, the large interface thermal resistance (ITR) that occurs between fillers and the organic matrix in polymer-based nanocomposites greatly limits their thermal conductive performance. Herein, through-plane direction aligned three-dimensional (3D) MXene/silver (Ag) aerogels are designed as heat transferring skeletons for epoxy nanoco

We demonstrate that the Mott metal-insulator transition (MIT) in single crystalline VO(2) nanowires is strongly mediated by surface stress as a consequence of the high surface area to volume ratio of individual nanowires. Further, we show that the stress-induced antiferromagnetic Mott insulating phase is critical in controlling the spatial extent and distribution of the insulating monoclinic and metallic rutile phases as well as the electrical characteristics of the Mott transition. This affords

We show that direct coupling of a dye-labelled DNA (acceptor) to a quantum dot (QD) donor significantly reduces the donor-acceptor distance and improves the FRET efficiency: a highly efficient FRET (approximately 88%) at a low acceptor-to-donor ratio of 2 has been achieved at the single-molecule level.

We demonstrated a hybrid nanogenerator (NG) exploiting both piezoelectric and triboelectric effects induced from ZnO nanoflakes (NFs)/polydimethylsiloxane (PDMS) composite films through a facile, cost-effective fabrication method. This hybrid NG exhibited not only high piezoelectric output current owing to the enhanced surface piezoelectricity of the ZnO NFs but also high triboelectric output voltage owing to the pronounced triboelectrification of Au-PDMS contact, producing a peak-to-peak output

We report Zn doped mesoporous TiO2 microspheres synthesized via a combined sol–gel and solvothermal method exhibiting excellent Li-ion insertion–extraction properties. The specific capacity of Zn doped mesoporous TiO2 microspheres was significantly higher than that of TiO2 nanopowder at high charge–discharge rates. The superior rate performance offered by Zn doped mesoporous TiO2 microspheres may be attributed to enhanced electronic and ionic conductivity, which was achieved by improving the don

Graphene has been functionalized with spiropyran (SP), a well-known photochromic molecule. It has been realized with pyrene-modified SP, which has been adsorbed on graphene by π-π interaction between pyrene and graphene. The field-effect transistor (FET) with SP-functionalized graphene exhibited n-doping effect and interesting optoelectronic behaviors. The Dirac point of graphene in the FET could be controlled by light modulation because spiropyran can be reversibly switched between two differen

Among transition metal oxides, vanadium oxides have received relatively modest attention for supercapacitor applications. Yet, this material is abundant, relatively inexpensive and offer several oxidation states which can provide a broad range of redox reactions suitable for supercapacitor operation. Electrochemical supercapacitors based on nanostructured vanadium oxide (V₂O₅) suffer from relatively low energy densities as they have low surface area and poor electrical conductivities. To overcom