製備金/二氧化鈦奈米顆粒應用於催化一氧化碳氧化反應

The Preparation of Au/TiO2 Nanoparticles for Catalytic CO Oxidation

陳俊榮(Chun-Jung Chen)

指導教授 ： 蘇昭瑾

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2012年)

摘要

本篇論文主要分為兩部分。第一部分結合傳統沉澱沉積法的較高合成穩定性與光還原法的較短的反應週期之優點，開發一新合成法「光輔助沉澱沉積法」，此一新合成法所製備出之金/二氧化鈦奈米顆粒應用於一氧化碳的氧化反應有較高催化效率。 穿透式電子顯微鏡 (TEM) 的數據顯示，在適當的反應條件下，金沉積在二氧化鈦奈米顆粒上的粒徑為3-5 nm間。吸附於TiO2表面之金離子，在UV光照射下之金屬化(metallization)成核過程係透過UV-Vis吸收光譜儀進行探討。此外，本研究應用實驗設計法分析控制因子之間的關係及意義，其中包含照光波長、照光強度、照光時間及乙醇添加量等進行分析，並找出最佳之實驗參數。實驗中利用氣相層析儀 (GC) 與微分熱掃描卡計檢測一氧化碳的轉化率，本研究所合成之Au/TiO2於室溫25 °C下，可達85 % 以上之一氧化碳轉換效果。本研究之第二部分係透過3C含金廢液作為金前驅物來源，並搭配第一部分研究的實驗設計法所得之最佳合成參數，進一步探討不同濃度的含金廢液對Au/TiO2觸媒催化效果之影響。最後，本研究利用全反射式螢光光譜儀 (TXRF) 之進行元素半定量分析，以了解廢液中金離子與其他金屬沉積於TiO2表面之情形。

關鍵字

二氧化鈦 ； 奈米金觸媒 ； 一氧化碳 ； 含金廢液

並列摘要

This study was separated into two parts. The first part of the study focused on synthesizing gold/titanium dioxide (Au/TiO2) nanoparticle as a catalyst for CO oxidation at room temperature. We have developed a photo-assisted deposition-precipitation (PA-DP) method which combined the advantages of deposition precipitation with better stability and photodeposition method with short reaction period to synthesis Au/TiO2 nanoparticle with high efficiency toward the CO conversion to CO2. The result of Transmission Electron Microscopy (TEM) shows that the size of Au deposited on TiO2 nanoparticles is in the range of 3-5 nm under the appropriate reaction condition. UV-Vis spectroscopy was used to monitor the photometallization and growth of gold nanoparticles. The absorbance band of Au approached the maximum after ~15 minutes UV light irradiation . In addition, design of experiment (DOE) is applied to analyze the correlation and significance of the control factors, including the wavelength of irradiation light, the light intensity, the irradiation time and the concentration of hole scavenger (ethanol). The CO conversion efficiency was monitored by both Differential Scanning Caloremeter (DSC) and Gas Chromatography (GC) techniques. In the second part of this study, gold-bearing wastewater from the 3C recycled wastes was the source of gold precursor. The optimal parameters obtaining from the first part of study was applied and investigated for samples of wastewater with different gold concentration.

並列關鍵字

Titanium Dioxide ； Gold nanoparticle catalyst ； Carbon monoxide ； Wastewater

參考文獻

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