本研究係以二氧化鈰為感測材料，利用簡易水熱法製備電阻式丙酮蒸氣感測器，旨在探討製備變因對感測元件最適化之選擇。藉由改變感測溫度與丙酮蒸氣濃度觀察對感測特性之影響，並進一步解析丙酮蒸氣分子在元件上之吸附行為。本實驗製程中以氧化鋁為基材，首先以熱蒸鍍法鍍覆指叉式金電極，接著利用濺鍍法沉積二氧化鈰晶種層，再透過水熱法成長二氧化鈰薄膜層，最後將元件煅燒提高二氧化鈰之結晶性。
在水熱法製備變因中探討水熱溫度對元件感測度的影響。由實驗結果顯示，當水熱溫度為150 ℃，反應時間為24小時(H150t24)，感測元件具有最高的感測靈敏度及較短的響應時間及回復時間(125 ℃、5000 ppm下，S = 2.55，τa = 24 s，τb = 20 s)。此外，利用FT-IR定性分析比較各元件之間活性座之多寡。
為了提升元件之感測效果，本研究透過添加金屬觸媒提升感測效能。由實驗結果發現，利用熱蒸鍍法將金奈米粒子(AuNPs)沉積在H150t24元件上，可以大幅提升元件之感測靈敏度。當金奈米粒子之沉積時間為100秒時，感測度(25 ℃、5000 ppm下，S = 143.77)為原始H150t24元件的56倍，除此之外，最佳感測溫度從125 ℃降至25 ℃，偵測極限亦由100 ppm降至10 ppm。另外，元件於室溫下感測不但有快速的響應及回復時間(25 ℃、5000 ppm下，τa=28 s，τb=27 s)也具有優異之氣體選擇性。
進一步解析丙酮蒸氣在元件上之吸附行為，結果顯示此吸附行為可由Langmuir isotherm來描述，且暫態響應之初始反應速率符合一階動力模式。綜合上述，本研究製備出高感度、響應快速之丙酮蒸氣感測器，適合用於低溫或室溫下偵測。

In this study, CeO2 and Au/CeO2 nanostructures were synthesized via simple hydrothermal method using cerium(III) nitrate hexahydrate and sodium hydroxide as starting materials and distilled water as solvent. Under optimal operating temperature (25 ℃), the response to 5000 ppm acetone of the Au/CeO2 sensor was 143.77, which was 55 times larger than that of the CeO2 sensor (125 ℃). Meanwhile, the low detection limit was decreased from 100 ppm to 10 ppm. The response and recovery time of the Au/CeO2 sensor were 28s and 27s, while that of the CeO2 sensor were 24 s and 20 s, respectively. The results revealed that Au/CeO2 sensor enhanced the sensing performances, which were attributed to the effect of the Au-doping. In addition, the behavior of acetone adsorbed on ceria was discussed.

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