近年來人類不斷消耗石化燃料，且人類對於能源的需求不斷增加，有效的回收大量廢熱與環保、低成本且高效率的新型能源成為重要的課題。本文研究最新一代的熱電材料硒化錫，藉由分子動力學與第一原理探討硒化錫的熱電係數，以及應用之潛能。
本文採用了非平衡態分子動力學與LAMMPS軟體進行計算模擬，探討硒化錫晶體的熱導率。再以第一原理進行電子結構及性質的計算，探討硒化錫的席貝克常數、功率因子與電導率。最後計算出硒化錫的熱電優值。
研究之結果顯示，逆向非平衡態熱導率模擬比非平衡熱導率模擬還要準確。硒化錫經過逆向非平衡態分子模擬計算的熱導率為1(W/mK)左右。與其他文獻對照，本文模擬結果與其他實驗 et al.所得到的結果相近。硒化錫的熱電優值ZT大約在500K之後落在0.8以上，而現今主流的熱電材料碲化鉍在500K約落在0.5。因而證實硒化錫儼然可以取代碲化鉍成為的一個新興的熱電材料。

Recently, human beings have continuously consumed fossil fuels and the demand for energy has been increasing. Effective recycling of large amounts of waste heat and environmentally friendly, low-cost and high-efficiency new energy sources has become an important issue. In this research, we studied the latest generation of thermoelectric material tin selenium. The thermodynamic coefficient of tin selenide and the potential of application are discussed by molecular dynamics and first principle.

In this paper, non-equilibrium molecular dynamics and LAMMPS software were used to calculate the thermal conductivity of tin selenide crystals. The electronic structure and properties were calculated by the first principle, and the Seebeck constant, power factor and electron conductivity of tin selenide were discussed. Finally, the thermoelectric figure of tin selenide is calculated.

Our study show that the reverse non-equilibrium thermal conductivity simulation is more accurate than the non-equilibrium thermal conductivity simulation. The thermal conductivity of tin selenide calculated by reverse non-equilibrium molecular simulation is about 1 (W/mK). Compared with other research, the simulation results in this paper are similar to those experimental teams. The thermoelectric figure ZT of tin selenide is 0.8 after about 500K, and the currently used thermoelectric material bismuth telluride is about 0.5 at 500K. Therefore, it has been confirmed that tin selenide can replace bismuth telluride to become a new type of thermoelectric material.

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