電泳沉積法製作光觸媒濾網與應用於降解甲醛氣體污染物之研究

Fabrication of photocatalyst filter by electrophoretic deposition applied to the degradation of formaldehyde gas pollutants

潘叔憶(Shu-I)

指導教授 ： 鄧敦平

國立臺灣師範大學/科技學院/工業教育學系/碩士(2011年)

摘要

本研究以定電流電泳沉積法製作二氧化鈦光觸媒濾網，並實際應用於甲醛氣體污染物之降解性能評估。電泳沉積工作流體是以藻酸鹽陰離子分散劑配合二階製程法將二氧化鈦粉末（Degussa P25）與水調配出不同濃度的TiO2/water奈米流體，並檢測與分析不同濃度與溫度下的理化特性。在電泳沉積製程方面，將針對不同製程參數對電泳沉積製程中沉積膜的表面特性與材質進行探討。在光催化實驗中，分析光觸媒沉積膜改質前後於紫外光與可見光照射下對甲基藍的降解性能。最後並製作光觸媒濾網循環箱，實際針對甲醛氣態污染物的降解性能進行測試。研究結果顯示，奈米流體於不同溫度下其理化特性均會改變。藉由控制工作電流與沉積時間可製作出表觀平整的沉積膜。在甲基藍降解實驗方面，最佳製程參數的樣本在紫外光照射下，No.5 /9mA/5min的樣本對甲基藍降解能力最佳，效果可達78.40%。在光觸媒改質方面，使用0.1M的硝酸鋰改質後於可見光照射下對甲基藍降解效果最佳（35.23%）。在甲醛氣體污染物降解方面，環境溫度的高低會影響光觸媒對甲醛氣體的降解能力，且經過硝酸鋰改質的光觸媒，無論是在紫外光或是可見光下均具有最佳的甲醛降解性能，成功開發可見光激發的光觸媒濾網，有效延伸光觸媒的應用範圍。

關鍵字

電泳沉積法 ； 甲醛氣體污染物 ； 二氧化鈦 ； 光觸媒

並列摘要

This study investigated the production of titanium dioxide photocatalyst film by electrophoretic deposition (EPD) at constant current, and the practical applications for the degradation of formaldehyde gaseous pollutants. The titanium dioxide powder (Degussa P25), alginate dispersant, and water were used to prepare different concentrations of TiO2/water nanofluids as a working fluid for EPD by a two-step synthesis. Analyzed the physical and chemical characteristics for the different concentrations of TiO2/water nanofluids at different temperatures. In the electrophoretic deposition process, the surface characteristics of the deposited film and the material properties are discussed for the different process parameters of EPD. In photocatalytic experiments of deposited film, the photocatalytic efficiency was measured for the degradation of methylene blue under UVA and visible light irradiation. Finally, a performance test for the degradation of gaseous formaldehyde in the photocatalytic circulation reactor was performed.
The results indicate that the TiO2/water nanofluids change their physical and chemical properties at different temperatures. In deposited film production, using a constant current for the electrophoretic deposition process, the operating current and deposition time can be controlled to obtain a homogenized and smooth deposited film. In the methylene blue degradation experiment, the optimal process parameters for the degradation of methylene blue were those in sample NO.5 /9 mA/5 min under UV irradiation is best（78.40%）. In photocatalyst modification, the optimal parameters for the degradation of methylene blue are modified by LiNO3 (0.1 M) under visible light irradiation is best（35.23%）. In the degradation of formaldehyde gas pollutants, the ambient temperature affects the photocatalytic degradation performance for formaldehyde, and the modification of the photocatalyst by LiNO3 yields the optimal degradation performance for formaldehyde under ultraviolet and visible light irradiation. The successful development of a photocatalytic filter excited by visible light could effectively extend the range of applications in this study.

並列關鍵字

electrophoretic deposition ； formaldehyde gaseous pollutants ； titanium dioxide ； photocatalyst

參考文獻

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