Rhyee Jong-Soo
Kyung Hee University · 材料科学
研究室紹介
Professor Rhyee Jong-Soo's research lab specializes in the development and optimization of advanced functional materials for energy conversion and nanoelectronic applications. The lab focuses on high-performance thermoelectrics, including nanostructured chalcogenides like PbTe, SnSe, and In4Se3-based compounds, with an emphasis on enhancing the thermoelectric figure-of-merit (ZT) through electronic band engineering, defect control, and lattice thermal conductivity reduction. The group also investigates two-dimensional transition metal dichalcogenides, such as MoSe2, for high-mobility, flexible electronics. Their work integrates advanced synthesis, structural characterization, and theoretical modeling to design materials with tailored electronic and thermal properties.
Research Overview
Research Output Trend
Figures are computed from collected data and may differ slightly.
Selected Papers
15Large-area and highly crystalline CVD-grown multilayer MoSe2 films exhibit a well-defined crystal structure (2H phase) and large grains reaching several hundred micrometers. Multilayer MoSe2 transistors exhibit high mobility up to 121 cm2 V−1 s−1 and excellent mechanical stability. These results suggest that high mobility materials will be indispensable for various future applications such as high-resolution displays and human-centric soft electronics. As a service to our authors and readers, th
Considerable efforts have been devoted to enhancing thermoelectric performance, by employing phonon scattering from nanostructural architecture, and material design using phonon-glass and electron-crystal concepts. The nanostructural approach helps to lower thermal conductivity but has limited effect on the power factor. Here, we demonstrate selective charge Anderson localization as a route to maximize the Seebeck coefficient while simultaneously preserving high electrical conductivity and lower
Single crystalline SnSe has been reported to exhibit the high thermoelectric zT value of 2.6 at 923 K along the b -axis direction, due to its low thermal conductivity [Zhao, L. D.; et al. Nature 2014, 508, 373]. However, the strongly anisotropic properties of the orthorhombic structure degrade the thermoelectric performance of polycrystalline SnSe, resulting in a low zT of 0.6 and 0.8 for Ag- and Na-doped SnSe, respectively. Here, we prepared Ag 0.01 Sn 0.99 Se 1– x S x ( x = 0, 0.10, 0.15, 0.20
The state-of-the-art record of thermoelectric figure-of-merit (ZT) of 1.53 at 425 °C is achieved by chlorine doping in In4Se3–xCl0.03 bulk crystalline materials as used for n-type thermoelectric energy harvesting. The low-dimensional property imparted by chlorine doping significantly increases the electrical conductivity and reduces the thermal conductivity resulting in a high power factor over a wide temperature range.
Carbon quantum dots (CQDs) are promising carbonaceous nanomaterials fortuitously discovered in 2004. CQDs are the rising stars in the nanotechnology ensemble because of their unique properties and widespread applications in sensing, imaging, medicine, catalysis, and optoelectronics. CQDs are notable for their excellent solubility and effective luminescence and, as a result, they are also known as carbon nanolights. Many strategies are used for the efficient and economical preparation of CQDs; ho
We report the high thermoelectric figure-of-merit (ZT) on the Se-deficient polycrystalline compounds of In4Se3−x (0.02≤x≤0.5) and the anisotropic electronic band structure. The Se-deficiency (x) has the effect of decreasing the semiconducting band gap and increasing the power factor. The band structure calculation for In4Se3−x (x=0.25) exhibits localized hole bands at the Γ-point and Y-S symmetry line, whereas the significant electronic band dispersion is observed along the c-axis. Here, we prop
We investigated the thermoelectric properties and electronic band structure calculation of Sn<sub>1−x</sub>Ag<sub>x</sub>Te and Sn<sub>1.03−x</sub>Ag<sub>x</sub>Te (<italic>x</italic> = 1, 3, 5, 7 mol%) compounds.
We investigate the thermoelectric properties of (CuI)<sub>0.003</sub>Bi<sub>2</sub>Te<sub>2.7</sub>Se<sub>0.3</sub>/Mo (Mo: 0.0, 0.9, 1.3, 1.8, 3.1, and 4.3 vol %) composites, which were synthesized by extrinsic phase mixing with hot press sintering. From X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDX) measurements, we confirm that micro-sized Mo particles are dispersed homogeneously in the (CuI)<sub>0.003</sub>Bi<sub>2</sub>Te<sub>2.7</sub>Se<sub>0.3</sub> matrix without
Sb<sub>2</sub>Te<sub>3</sub>/Ag<sub>2</sub>Te (ST/AT) composites with ST/AT molar ratios of 1/1, 2/1, 4/1, 8/1, 16/1, and 32/1 were synthesized, and high <italic>ZT</italic> values were achieved compared with other Pb-free p-type chalcogenide thermoelectric materials.
We present thermoelectric properties and electronic structure of the series compounds of In4Se3−xTex (0.0≤x≤3.0). Even if the Te-doping is an isoelectronic substitution, we found that the electron dominated carrier transport in Se-rich region (x≤0.2) evolves into the electron-hole bipolar transport properties in Te-rich region (x≥2.5) from the temperature-dependent thermal conductivity κ(T), Seebeck coefficient S(T), and Hall coefficient RH(T) measurements. The electronic band structures of In4S