臺灣博碩士論文加值系統

本研究利用溶膠凝膠法(Sol-gel Process)結合靜電紡絲法(Electrospinning)製備二氧化錫(SnO2)奈米纖維，配合鋅鐵氧體(ZnFe2O4)溶液於纖維表面浸漬一層鋅鐵氧體薄膜，並通過改變實驗參數觀察其特性與應用於氣體感測器上。
實驗結果表明使用重量百分比為23 wt%的二氧化錫前驅液配合18 kV的紡絲電壓能夠獲得最佳的二氧化錫奈米纖維，且於250℃的工作溫度下對於10 ppm的二氧化氮(NO2)有最佳選擇性且具有1140%的優良響應、響應時間和回復時間分別為63秒和304秒。而複合鋅鐵氧體薄膜的二氧化錫-鋅鐵氧體氣體感測器同樣對於10 ppm的二氧化氮有最佳的選擇性，可於室溫環境下進行穩定的氣體感測，且響應值為8.5%、響應時間和回復時間分別為55秒、267秒。再複合鋅鐵氧體薄膜後，雖然響應值方面並未有得到改善，但於工作溫度方面卻得到明顯改善，工作溫度從原本的250℃降低至室溫。
現階段二氧化錫-鋅鐵氧體氣體感測器已能於室溫環境下進行穩定的氣體感測，接下來可以透過摻雜貴金屬等方式進一步改善材料的電特性，以提升氣體感測性能，並結合氣體感測器零組件，設計出一款能實際應用的氣體感測器。

In this study, tin dioxide (SnO2) nanofibers were prepared by a Sol-gel process combined with Electrospinning, and a zinc ferrite (ZnFe2O4) film was impregnated on the surface of the fibers with zinc ferrite solution, and its properties and application to gas sensors were observed by changing the experimental parameters.
The experimental results show that the best tin dioxide nanofiber can be obtained by using 23 weight% of tin dioxide precursor solution with 18 kV spinning voltage, and the best selectivity for 10 ppm nitrogen dioxide (NO2) at 250°C with excellent response of 1140%, response time and recovery time of 63 seconds and 304 seconds respectively. The tin dioxide-zinc ferrite gas sensor with the composite zinc ferrite film also has the best selection for 10 ppm nitrogen dioxide and can perform stable gas sensing at room temperature with a response value of 8.5%, response time and recovery time of 55 seconds and 267 seconds respectively. After compounding the zinc ferrite film, although the response value was not improved, the operating temperature was significantly improved, and the operating temperature was reduced from the original 250°C to room temperature.
At this stage, the tin dioxide-zinc ferrite gas sensor has been able to carry out stable gas sensing at room temperature, the next can further improve the electrical properties of the material by mixing precious metals, etc., in order to enhance the gas sensing performance, and the combination of gas sensor components to design a practical application of the gas sensor.

摘要 i
Abstract ii
誌謝 iv
目錄 v
表目錄 ix
圖目錄 x
符號說明 xiii
第一章 緒論 1
1.1前言 1
1.2研究動機與目的 4
第二章 基礎原理與文獻回顧 5
2.1二氧化錫(Stannic oxide) 5
2.2尖晶石鐵氧體(Spinel Ferrite) 6
2.3靜電紡絲 8
2.3.1靜電紡絲簡介 8
2.3.2靜電紡絲影響因素 10
2.4氣體感測器 12
2.4.1氣體感測器簡介 12
2.4.2半導體氣體感測器 14
2.4.3氣體感測響應數值計算方式 16
第三章 實驗步驟與分析方法 17
3.1實驗架構 17
3.2實驗藥品 19
3.3實驗方法與流程 20
3.3.1 SnO2金屬氧化物半導體纖維薄膜製備 20
3.3.2 ZnFe2O4尖晶石薄膜製備 21
3.4氣體感測器電極晶片製作 22
3.5氣體感測測試 25
3.6製程使用設備 26
3.6.1 超音波震盪清洗機 26
3.6.2 精密天秤 26
3.6.3 加熱磁石攪拌機 27
3.6.4 烘箱 27
3.6.5 水平式靜電紡絲機 28
3.6.6 高溫爐 28
3.7實驗分析儀器 29
3.7.1 高溫二維X-ray廣角繞射儀(XRD) 29
3.7.2 多功能環境場發掃描式電子顯微鏡(SEM) 30
3.7.3 歐傑電子能譜儀(ESCA) 31
3.7.4 氣體感測儀器 32
第四章 結果與討論 33
4.1 SnO2金屬氧化物半導體纖維材料性質探討 33
4.1.1 SnO2金屬氧化物半導體粉末之XRD分析 33
4.1.2 不同PVP含量對SnO2金屬氧化物半導體纖維直徑影響 35
4.1.3 SnO2金屬氧化物半導體纖維不同紡絲電壓之SEM分析 38
4.3.4 SnO2纖維的氣體選擇性 42
4.3.5 SnO2纖維於不同工作溫度下對NO2的響應 43
4.3.6 SnO2纖維於不同濃度的NO2響應 46
4.3.7 SnO2纖維的氣體感測穩定性 49
4.2 ZnFe2O4尖晶石薄膜 50
4.2.1 ZnFe2O4不同燒結溫度之XRD分析 50
4.2.2 ZnFe2O4薄膜之SEM分析 52
4.3 SnO2/ZnFe2O4複合纖維薄膜 55
4.3.1 SnO2/ZnFe2O4複合纖維薄膜之XRD分析 55
4.3.2 SnO2/ZnFe2O4複合纖維薄膜之SEM分析 56
4.3.3 SnO2/ZnFe2O4複合纖維薄膜之XPS分析 58
4.3.4 SnO2/ZnFe2O4複合纖維薄膜於不同工作溫度下對NO2的響應 60
4.3.5 SnO2/ZnFe2O4複合纖維薄膜於不同濃度的NO2響應 64
4.3.6 SnO2/ZnFe2O4複合纖維薄膜的氣體感測穩定性 66
4.3.7 SnO2/ZnFe2O4複合纖維薄膜的氣體選擇性 67
4.4 SnO2/ZnFe2O4半導體氣體感測器之感測機制推測[67-71] 68
4.5 氣體感測器與其他研究之氣感性質比較 71
第五章 結論 72
5.1結論 72
5.2未來展望 73
參考文獻 74
個人簡歷 85

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