• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.126-127
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• 2007

Sn-filled and Fe-doped $CoSb_3$ skutterudites were synthesized by encapsulated induction melting. Single ${\delta}$-phase was successfully obtained by subsequent annealing and confirmed by X-ray diffraction analysis. Temperature dependences of Seebeck coefficient, electrical resistivity and thermal conductivity were examined from 300 K to 700 K. The positive Seebeck coefficient confirmed the p-type conduction. Electrical resistivity increased with increasing temperature, which shows that the $Sn_zCo_3FeSb_{12}$ skutterudite is highly degenerate. Thermal conductivity was reduced by Sn-filling because the filler atoms acted as phonon scattering centers in the skutterudite lattice. Thermoelectric figure of merit was enhanced by Sn filling and its optimum filling content was considered to be z=0.3 in the $Sn_zCo_3FeSb_{12}$ system.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.308-308
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• 2012

Electrodeposition of thermoelectric materials, including binary and ternary compounds, have been attracting attentions, because its many advantages including cost-effectiveness, rapid deposition rate, and ease of control their microstructure and crystallinity by adjusting electrodeposition parameters. In this work, $Bi_xTe_y$ films were potentiostatically electrodeposited using Au/Ni(80/20 nm)/Si substrate as the working electrode in solutions consisting of 10mM $TeO_2$ and 1M $HNO_3$ where $Bi(NO_3)_3$ was varied from 2.5 to 10 mM. Prior to electrodeposition potentiostatically, linear sweep voltammograms (LSV) were acquired with a standard three-electrode cell. The $Bi_xTe_y$ films deposited using the electrolyte containing low Bi ions shows p-type conductivity, which might be attributed by the large incorporation of Te phases. Near stoichiometric $Bi_2Te_3$ thin films were obtained from electrolytes containing 5mM $Bi(NO_3)_3$. This film shows the maximum Seebeck coefficient of $-100.3{\pm}12.7{\mu}V/K$. As the increase of Bi ions in electrolytes decreases the Seebeck coefficient and resistivity. The maximum power factor of $336.2{\mu}W/m{\cdot}K^2$ was obtained from the film deposited using the solution of 7.5mM $Bi(NO_3)_3$.

• Journal of the Korean Solar Energy Society
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• v.39 no.1
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• pp.21-32
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• 2019

Solar hot water system produces hot water using solar energy. If it is not used effectively, overheating occurs during the summer. Therefore, a lot of research is being done to solve this. This study develops thermoelectric power module applicable to solar hot water system. A thermoelectric material can directly convert thermal energy into electrical energy without additional power generation devices. If there is a temperature difference between high and low temperature, it generate power by Seebeck effect. The thermoelectric module generates electricity using temperature differences through the heat exchange of hot and cold water. The water used for cooling is heated and stored as hot water as it passes through the module. It can prevent overheating of Solar hot water system while producing power. The thermoelectric module consists of one absorption and two radiation part. There path is designed in the form of a water jacket. As a result, a temperature of the absorption part was $134.2^{\circ}C$ and the radiation part was $48.6^{\circ}C$. The temperature difference between the absorption and radiation was $85.6^{\circ}C$. Also, The Thermoelectric module produced about 122 W of irradiation at $708W/m^2$. At this time, power generation efficiency was 2.62% and hot water conversion efficiency was 62.46%.

• Journal of the Korean Electrochemical Society
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• v.22 no.3
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• pp.79-86
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• 2019

Most of low-grad heat (< $200^{\circ}C$) generated from industrial process and human body, is abandoned as waste heat. To harvest the waste heat, the thermoelectrics (TE) technology has been widely investigated so far. However, TE suffers from poor performance and high material cost. As an alternative to the TE device, the thermoelectrical cell (TEC) is gaining growing attention these days. The TEC features several advantages such as high Seebeck coefficient, low cost and design flexibility compared to TE, but its commercial viability was limited by its low heat-to-electricity conversion efficiency. However, recent reports have demonstrated that the performance of TEC can be markedly improved by employing novel electrode/electrolyte materials and by optimizing cell design. This article summarizes the recent progress of TECs in terms of the redox couples, electrolyte solvents and additives, electrode materials and cell design.

• Journal of Convergence for Information Technology
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• v.11 no.2
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• pp.90-97
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• 2021

In this study, a Bi2Te3 thermoelectric generator (TEG) was fabricated to convert unused thermal energy into useful electrical energy. For the performance test, a dedicated experiment device consisting of a heating block operating with cartridge heaters and a cooling block through which a refrigerant flows was constructed. A 3×3 array of thermocouples was mounted on the heating block and the cooling block, respectively, to derive the temperature fields and heat transfer rate onto both sides of the TEG. Experiments were conducted for a total of 9 temperature differences, obtaining V-I and P-R curves. The results of 7 variables including Seebeck coefficients that have a major effect on performance were presented as a function of the temperature difference. The feasibility of the energy recovery performance of the developed TEG was verified from the maximum power output of 7.5W and conversion efficiency of 11.3%.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.162-163
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• 2013

Single-crystal InGaZnO (IGZO) thin films were spontaneously formed as periodic layered structure along the c-axis by thermal treatment at high temperature. when the IGZO superlattice were synthesized by sol-gel method, the effects of preferred growth orientations and the flatness of ZnO buffer layer were investigated. $InGaO_3(ZnO)_2$ superlattice were favorably formed on ZnO buffer layer with single preferred orientation. Futhermore, it showed relatively high Seebeck coefficient and power factor.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.5
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• pp.10-19
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• 1998

The erosion of electrode in spot welding of aluminium alloy by direct current is dependent on the electric polarity. The positive electrode is much more eroded than the negative one. To explain this phenomenon, Peltier effect has been generally accepted as a unique theory. In this study Peltier effect was evaluated by calculations on the basis of some references and experiments. The difference of heat generated by Peltier effect on both electrode surfaces was, however, only 4% of total heat generated during wel- ding. Because of insufficient explanation, Kohler theory, which is mainly affected by thin oxide film, was introduced. A theoretical calculation showed 17% of the temperature difference between the positive and negative electrode, in case "surface voltage" resulted from oxide film was 30% of total contact voltage. This revealed that the erosion of electrode could be more affected by Kohler theory than effect.an effect.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1455-1458
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• 2007

In this research, a polycrystalline silicon (poly-Si) film layer for micro thermoelectric generator (TEG) was fabricated. The fabrication process of the thermoelectric poly-Si film layer is explained. The P-type and N-type poly-Si films were fabricated on a tetra ethoxy silane (TEOS) layer with a supporting Si wafer. Seebeck coefficient and electrical conductivity were measured, including the transport properties such as the hall coefficient, hall mobility and carrier concentration. The design parameters for a rapid thermal process (RTP) were decided based on the experimental results. The measured power factors of the P-type and N-type were $21.2\;{\mu}Wm^{-1}K^{-2}$ and $26.7\;{\mu}Wm^{-1}K^{-2}$, respectively.

• Journal of Powder Materials
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• v.8 no.2
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• pp.110-116
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• 2001

Abstract To investigate the effect of mechanical alloying process to thermoelectric properties of PbTe sintered body, Pb-Te mixed powder with Pb : Te : 1 : 1 composition was mechanically alloyed using tumbler-ball mill. Thermoelectric properties of the sintered body were evaluated by measuring of the Seebeck coefficient and specific electric resistivity from the room temperature to 50$0^{\circ}C$. Sintered body of only mechanically alloyed PbTe powder showed p-type behavior at the room temperature, and occurred type transition from p-type to n-type at about 30$0^{\circ}C$. PbTe sintered body which was fabricated using heat treated powder in $H_2$ atmosphere after mechanical alloying showed stable n-type behavior under 50$0^{\circ}C$. N-type PbTe sintered body fabricated by mechanical alloying process had 4 times higher power factor than that fabricated by the melt-crushing process. Application of a mechanical alloying process to fabricate of n-type PbTe thermoelectric material seemed to be useful to increase the power factor of PbTe sintered body.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.389-392
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• 2007

본 연구는 지벡(Seebeck)효과를 이용한 열전발전소자의 효율증가를 위한 Cooling System에 대한 연구이다. 열전발전소자는 Hot side와 Cool side의 온도차에 의해 전력발생 효율이 결정되며 열전발전소자가 견딜 수 있는 Hot Side의 온도는 고정돼있는 반면, Cool Side의 온도는 Cooling System의 설계에 따라 온도 설정이 가능하다. 본 연구는 Cooling System은 방열판과 팬으로 구성된 공랭방식을 사용하였고, 냉각효율을 높이기 위해 방열판의 크기 및 모양 팬의 크기와 속도 공기의 이동방향에 따른 냉각특성을 실험하였고 그에 따른 특성들을 논하고자 한다.