Sang‐il Kim
성균관대학교 材料공학과 · 재료과학
Sang-il Kim 교수의 연구실은 열전재료의 전자적 및 열적 성능을 극대화하기 위한 전략적 전자구조 설계를 핵심으로 합니다. 특히 밴드 콘버전스, 평면 밴드 형성, 도핑을 통한 전도도 향상 및 열전도도 저감 기법을 응용하여 고성능 열전 소재를 개발하고 있습니다. 나노구조 및 에피택시얼 박막을 활용한 고성능 열전막 제작과 전이 기술도 핵심 연구 분야로, 고온에서의 효율성 향상과 응용 가능성을 확장하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Band engineering is one of core approaches to improve the performance of thermoelectric materials via the Seebeck coefficient enhancement. However, the conclusion that is often found in the literature is that the band engineering has been achieved in haste when a simple increase in a density-of-states effective mass is observed. In this review, a theoretical background to the band convergence, the most effective band engineering strategy to improve the thermoelectric power factor, is provided. I
Thermoelectrics, which can generate electricity from a temperature difference, or vice versa, is a key technology for solid-state cooling and energy harvesting; however, its applications are constrained owing to low efficiency. Since the conversion efficiency of thermoelectric devices is directly obtained via a figure of merit of materials, zT, which is related to the electronic and thermal transport characteristics, the aim here is to elucidate physical parameters that should be considered to u
An improved thermoelectric figure of merit (<italic>zT</italic>) of 0.14 at 795 K was obtained in 7% Si doped InSe due to the emergence of the flat band.
Cation substitutional doping is an effective approach to modifying the electronic and thermal transports in Bi₂Te₃-based thermoelectric alloys. Here we present a comprehensive analysis of the electrical and thermal conductivities of polycrystalline Pb-doped p-type bulk Bi<sub>0.48</sub>Sb<sub>1.52</sub>Te₃. Pb doping significantly increased the electrical conductivity up to ~2700 S/cm at <i>x</i> = 0.02 in Bi<sub>0.48-x</sub>Pb<sub>x</sub>Sb<sub>1.52</sub>Te₃ due to the increase in hole carrier
Separation of epitaxial thin films on a growth substrate and transfer onto other materials for functional heterostructures have boosted the transformative impact on science and technology. However, this scheme has proved challenging in thin-film thermoelectrics but promises a vast range of applications beyond the limited device configurations of bulk thermoelectrics. Here, the high-quality Bi0.5Sb1.5Te3 (BST) epitaxial thin film on a sapphire substrate grown by spontaneous van der Waals epitaxy
Bi2Te3 is a good candidate to be used in thermoelectric generators. For a higher efficiency of the generators, shifting the temperature at which Bi2Te3 performs best to higher temperatures is required. Bipolar thermal conductivity suppression is the most effective approach to improve high-temperature thermoelectric performance. However, characterization of the bipolar thermal conductivity is challenging because it is related to individual contribution to Seebeck coefficient and electrical conduc
Excess Cu has been reported as an effective way to enhance the thermoelectric performance of n-type Bi2Te3-based alloys as well as to secure the reproducibility of their electronic properties. However, the effect of Cu doping into Bi2Te3 lattice is also known to be complex since Cu can occupy either interlayer or cation/anion sites, depending on conditions. Herein, Cu doping behavior in a binary Bi2Te3 prepared by a conventional melt-solidification process was demonstrated, and corresponding cha
