本研究係以柱狀氧化鋅(ZnO NR)元件作為丙酮感測器，旨在探討元件之製備變因對丙酮感測特性之影響，並進一步解析丙酮在元件上之吸附行為。製備元件時，以氧化鋁板為基材，在其上先鍍覆指叉式金電極，接者濺鍍一晶種層，然後採用水熱法成長柱狀氧化鋅，作為感測膜材。為提升元件對丙酮之感測性能，進一步沉積銀粒於ZnO NR上而得Ag/ZnO元件。
在水熱條件之探討上，分別改變溫度及時間，由實驗結果顯示，以85 ℃ 水熱1小時所製備之T85t1元件，對丙酮具有最大之感測靈敏度(265℃，S=9.49)，此係因其柱狀結構擁有最大之感測面積所致。但此元件響應及回復時間長(240 ℃、1000 ppm下，τa = 25.5 min，τb = 100.9 min)，為一大缺點。
為進一步提升感測之靈敏度，並降低響應及回復時間，本研究利用熱蒸鍍將銀粒子沉積於T85t1元件上，探討銀沉積時間其對丙酮感測之影響。由結果可知，銀沉積15秒之T85t1Ag15元件，所得之感測性能為最佳。改變感測溫度在215 ℃ ~315 ℃，濃度200 ppm ~ 1000ppm間，發現240 ℃、1000 ppm下，靈敏度達 216.89，約為T85t1元件之約30倍，且響應與回復時間亦明顯縮短(τa =13.23 min，τb =12.87 min)。此係因銀與氧化鋅之相互作用，銀之電子遷移至氧化鋅上，而增加銀對氧之親和力，因此，能吸附更多氧分子，並溢流至氧化鋅上；另一方面，銀之存在可使氧化鋅之氧空缺增加，進而提高丙酮之吸附與氧化反應。此外，銀之擔載，可使感測溫度下降，且縮短響應、回復時間。
由穩態感測結果分析顯示，丙酮在Ag/ZnO上之吸附行為可以Langmuir Adsorption模式來加以描述。利用迴歸分析求出不同溫度下之平衡常數，並由van’t Hoff equation求得反應熱、反應熵分別為 -25.03 kJ/mol、-41.90 J/K mol。

In this study, Ag/ZnO used to detect acetone vapor was synthesized on alumina substrate by low-temperature hydrothermal method and evaporation. As expected, the Ag/ZnO demonstrated dramatic improvements in sensing performances compared with pure ZnO nanorods. For example, the optimal sensing temperature was reduced from 265 ℃ to 240 ℃. The response of Ag/ZnO device to 1000 ppm acetone was 216.89, which was nearly 30 times higher than that of primary ZnO at 240 ℃. Meanwhile, the response and recovery time were also obviously shortening. It was attributed to introduce Ag into ZnO would change the band diagram and the Ag showed positive dipole moment. It caused the more oxygen would be adsorbed and provide more active sites to facilitate the interaction between acetone and Ag/ZnO nanorods through the spillover effect.

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