氧化銦錫奈米晶粒之合成與一氧化碳氣體感測研究

Synthesis of Indium Tin Oxide Nanocrystals for Carbon Monoxide Sensing

黃士賢(Shih-Sian Huang)

指導教授 ： 楊家銘

國立清華大學/理學院/化學系/碩士(2015年)

https://doi.org/10.6843/NTHU.2015.00106

摘要

本論文以非水溶液凝膠-溶膠法合成二氧化錫及氧化銦錫奈米顆粒，並研究其於一氧化碳感測活性。在合成中我們利用配位基對錫前驅物水解縮合速率的影響，調控二氧化錫晶粒大小，並且利用不同金屬前驅物的組合，合成不同錫銦比之氧化銦錫奈米顆粒。透過X光粉末繞射、穿透式電子顯微鏡以及感應耦合電漿質譜來對合成的奈米晶粒進行結構、晶粒尺寸與成分分析。合成的二氧化錫奈米晶粒具有高結晶性，且吡啶以及水的加入可以有效地調控晶粒尺寸。氧化銦錫奈米晶粒之晶粒尺寸會隨著錫含量的下降而增加，且當合成液中Sn/In比達5.67時氧化銦錫會由金紅石結構轉變成立方結構。應用於偵測一氧化碳氣體研究中我們發現Sn/In比為3之氧化銦錫，反應性較二氧化錫奈米晶粒高，且具有較低的操作溫度(150 ℃)。為了降低感測時間，我們利用電阻值變化速度取代平衡時電阻，推算變速度與濃度之關聯方程式，並利用實驗證實可用此式推算一氧化碳濃度大幅縮短反應時間從數分鐘減少至50秒。

關鍵字

氧化銦錫 ； 一氧化碳 ； 氣體感測

並列摘要

In the thesis, we aimed to synthesize tin oxide and indium tin oxide nanocrystals via non-aqueous sol-gel route and study the activity of these materials for carbon monoxide sensing. Different ligands were used to control the size of the nanocrystals, and indium tin oxide of varied tin/indium ratio were prepared with proper combination of metal precursors. The obtained materials were characterized by powder X-ray diffraction, transmission electron microscopy, inductively coupled plasma mass spectrometry. The results indicated that tin oxide nanocrystal were highly crystalline, and the size of tin oxide could be well controlled by the addition of pyridine or water. For indium tin oxide nanocrystals, the size increased, as the molar ratio of tin/indium ratio decreased, and the nanocrystals with tin/indium ratio lower than 5.67 caused phase transformation from rutile to cubic phase. Results of carbon monoxide sensing indicated that indium tin oxide nanocrystals with 25 % of indium showed better response at lower operating temperature than tin oxide nanocrystals. We proposed an equation based on the reaction mechanism and reaction kinetics to estimate the concentration of carbon monoxide, and the results confirmed fair accuracy of the method.

並列關鍵字

Indium Tin Oxide ； Carbon Monoxide Sensing

參考文獻

[4] Omaye, S. T., Toxicology 2002, 180, 139-150.

[6] Seinfeld, J. H., Atmospheric Chemistry and Physics: From Air Pollution to Climate Change. Wiley: 2006; p 1232.

[12] Morrison, S. R., Sens. Actuators 1982, 2, 329-241.

[14] Marton, J. P., J. Electrochem. Soc. 1976, 123, 199-205.

[16] Gentry, S. J.; Jones, T. A., Sens. Actuators 1986, 10, 141-163.