陽極處理法製備奈米介孔三氧化鎢應用於 光催化染劑降解及pH感測器之研究

Preparation of Mesoporous Tungsten Oxide in Photocatalytic Degradation of Dyeing Agent and pH sensor by Anodic Method

朱世瑋(Shih-Wei Chu)

指導教授 ： 黃英邦

共同指導教授 ： 蔡木村(Mu-Tsun Tsai)

國立虎尾科技大學/工程學院/材料科學與綠色能源工程研究所/碩士(2012年)

https://doi.org/10.6827/NFU.2012.00205

摘要

本研究第一部份是以陽極處理法製備出奈米介孔三氧化鎢；以鎢片為陽極，白金為陰極，電解液分別有二甲基亞碸(Dimethyl sulfoxide，DMSO)、磷酸(H3PO4)和氫氟酸(HF)之混合電解液，以及硫酸(H2SO4)電解液，在恆溫20 ºC，陽極處理反應時間分別為4與8小時，固定電流為1 A，在鎢基材上製備蝕刻出奈米介孔三氧化鎢(WO3)薄膜。將WO3經過300、400、500及600 ºC退火處理，持溫兩小時。利用XRD分析樣品之晶體結構，以FE-SEM觀察樣品之表面及斷面形貌。
第二部份是將不同陽極處理時間及退火處理的奈米介孔三氧化鎢在紫外光照下進行光電流量測，藉以評估其光電轉換效率；其次，將不同陽極處理時間及退火處理的奈米介孔三氧化鎢分別置入10 ppm的酸性橙色7號染劑水溶液(AO 7)中，經400W的紫外光照射3小時，每15分鐘取樣一次，並以分光度計量測光照後之染劑濃度，溶液濃度都有明顯的降低。
第三部份是將不同陽極處理時間及退火處理的奈米介孔三氧化鎢分別置入pH 2、4、7及10的標準液中，測試對不同氫離子濃度(pH值)的電位感應性能，其感應靈敏度及響應時間均有良好的效果，由實驗結果顯示，本研究製作出的奈米介孔三氧化鎢適合應用在光觸媒染劑降解與pH感測器上。

關鍵字

三氧化鎢 ； 陽極處理法 ； pH感測器 ； 氫離子濃度 ； AO7

並列摘要

There are three parts in this study. Firstly, we report the preparation of mesoporous tungsten oxide by potentiostatic anodizing process. Mesoporous tungsten oxide (WO3) are manufactured by anodization with electrolyte of mixture of Dimethyl sulfoxide (DMSO), phosphoric acid (H3PO4),hydrofluoric acid (HF) and sulfuric acid (H2SO4), tungsten foil as anode and platinum as cathode at 20 ºC temperature and 4 h, 8 h anodizing time, respectively under 1 A constant ccurrent condition. After heat treatment at 300, 400, 500 and 600ºC temperature for 4 h and 8 h respectively. The X-ray diffraction (XRD) patterns and field emission scanning electron microscope (FE-SEM) of heat-treated specimens obtained in various heating temperature were also studied.
Secondly, the electro-optic transfer efficiency of WO3 with different anodizing time and heat treatment were evaluated after photocurrent measurement conducted under UV radiation. Furthermore, the photocatalytic degradation of dyeing agent for acid orange 7 (AO7) at 10 ppm concentrations by the WO3 with different anodizing time and heat treatment were carried out under 400W UV radiation for 3h respectively. Spectrophotometer confirmed that concentration was greatly reduced.
Thirdly, use prepared electrodes in several buffers pH = 2, 4, 7 and 10 to test the potential sensing performance of the different hydrogen ion concentrations. The prepared sensors have good sensitivity and response time of the induced effects. Experimental results show that the WO3 were suitable for Photocatalysts and pH sensor applications.

並列關鍵字

Mesoporous tungsten oxide ； Potentiostatic anodization ； photocatalyst ； pH sensor ； AO7

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