熱壓對於 3-D碲硒化鉍電鍍薄膜熱性質之影響

Influence of Hot-pressing on Thermoelectric Properties of 3-Dimension Bismuth-Telluride-Selenium Film

郭尚哲(SHANG-JHE GUO)

指導教授 ： 林昭任

國立中正大學/工學院/化學工程學系/碩士(2013年)

摘要

本實驗為利用聚苯乙烯微球(polystyrene sphere)進行電泳法製作三維結構基板，並於基板常壓電鍍碲硒化鉍熱電材料，藉由改變沉積電位和電流輔助退火溫度與時間以及薄膜經熱壓再退火後對熱電材料之熱電性質影響。實驗結果顯示，當沉積電位為-0.15Ｖ時，電沉積之碲硒化鉍之組成為Bi2Te2.69Se0.31時，具有最大之power factor值，且當退火溫度以及退火時間增加時，Power factor值亦隨之增加，並於退火溫度為305℃以及退火時間為8min時，有最大之Power factor值約為260μW/K2m。當將薄膜以55kg/cm2熱壓5min後，再經305℃電流輔助退火，其電阻率小於未熱壓過之薄膜，於退火時間為5min時，Power factor由260μW/K2m提升至419μW/K2m。

關鍵字

電流輔助熱處理 ； 碲硒化鉍 ； 熱電材料 ； 熱壓法

並列摘要

This study was to investigate the preparation of a three-dimensional (3-D) thermoelectric material of Bi2Te3-ySey by electrodepositing Bi2Te3-ySey in a 3-D polystyrene (PS) template. The 3-D PS template was made of electrophoretic depositing PS sphere on the ITO glass substrate, the influence of thermoelectric property of thermoelectric materials is investigated by changing the deposition potential, current-assisted annealing temperature, time and hot pressing before current-assisted annealing. The results revealed that the power factor has maximum value when the deposition potential is at -0.15V and the composition of bismuth-telluride-selenium is Bi2Te2.69Se0.31. the power factor is increasing with annealing temperature and time increasing, it has maximum value of power factor is about 260μW/K2m at 305℃ for annealing temperature and 8min for annealing time. When the film is hot pressed by 5min, and then through the current-assisted annealing at 305℃, the results showed that the resistivity is smaller than the non-hot pressed film, Power factor improved by the 260μW/K2m to 419μW/K2m at 5min for annealing time.

並列關鍵字

electric current assisted thermal treatment ； Bismuth-Telluride-Selenium ； Thermoelectric material ； hot press treatment

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