本研究針對Ag2Se低溫熱電材料進行優化，透過機械合金化、二次燒結及熱電複合材料等技術，提升其熱電性能。研究結果顯示，在轉速450 rpm、合金化時間10分鐘的條件下，機械合金法可快速合成高純度Ag2Se相。經過溫度573 K的放電等離子一次燒結後，樣品的ZT值介於0.75至0.95之間，展現穩定且優異的熱電性能。透過二次燒結技術，成功提升樣品密度至99% 並提高電導率，同時透過縮小晶粒尺寸降低熱導率，使ZT值進一步提升至1.6至2.4之間。此外，本研究針對不同Ag-Se比例進行優化，在Ag56.6Se43.4比例下獲得高導電率（13 × 104 S/m）及低導熱率（0.1 W/mK）。並利用複合材料技術，將Ag56.6Se43.4作為第二相摻入Ag2Se基體時，可有效提升熱電性能，且當加入量達20% 時，ZT值達約8，展現出卓越的熱電性能。本研究證實，透過精確控制合金組成及利用二次燒結及熱電複合材料技術，可顯著提升Ag2Se的熱電性能，展現其在低溫能源回收應用中的潛力，並提升材料的穩定性與實用性，促進其產業化發展。

This study optimizes Ag2Se thermoelectric materials for low-temperature applications using mechanical alloying and secondary sintering techniques to enhance thermoelectric performance. The results indicate that mechanical alloying at a rotational speed of 450 rpm for 10 minutes efficiently synthesizes a high-purity Ag2Se phase. After initial spark plasma sintering at 573 K, the samples exhibited ZT values ranging from 0.75 to 0.95, demonstrating stable and excellent thermoelectric properties. The application of a secondary sintering process increased the sample density to 99% and improved electrical conductivity. Simultaneously, grain size reduction lowered thermal conductivity, further enhancing the ZT value to a range of 1.6 to 2.4.

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