M(Cu, Ag, Pt)/TiO2覆膜光纖進行二氧化碳光催化還原

CO2 Photo Reduction Using Optical-fiber Coated with M(Cu, Ag, Pt)/TiO2 Catalysts

吳姿樺(Tzu-Hua Wu)

指導教授 ： 吳紀聖

國立臺灣大學/工學院/化學工程學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.01233

摘要

為了解決二氧化碳溫室氣體和能源問題，本研究於容納216根光纖之光反應器內，以100W高壓汞燈、波長365nm、光反應器溫度348K、流動式穩定狀態氣相系統中進行二氧化碳光催化還原反應。利用改良式熱水解法製備一系列TiO2、Cu/TiO2、Ag/TiO2、Pt/TiO2覆膜液，藉由浸漬覆膜法於直徑為0.1mm之光纖表面。由SEM之觀測，光纖表面的觸媒顆粒略呈圓形，粒徑約為10-20nm，觸媒層厚約26-33nm，並具有許多奈米級孔隙。經XRD繞射圖譜分析觸媒皆為anatase晶相，且紫外-可見光吸收波長約在350nm處。由XPS表面分析結果顯示，負載於二氧化鈦的Cu、Ag及Pt等金屬，分別以Cu+、Ag0及Pt2+或Pt4+存在於二氧化鈦表面。實驗結果發現，當光強度增強時，觸媒活性也隨之增加。以GC-FID測得主要產物為甲醇，及其他微量產物甲酸、甲酸甲酯等，銅、銀、鉑等過渡金屬的添加皆有效地提高甲醇的產率。

關鍵字

光催化還原 ； 光纖反應器 ； 二氧化碳 ； 二氧化鈦

並列摘要

In order to remedy the greenhouse gas CO2 and energy shortage, the photoreduction of CO2 is studied in a UV-illuminating steady-state gas photo-reactor with 216 optical fibers by a 100W high-pressure Hg lamp with wavelength 365nm at 348K. M(Cu, Ag, Pt)/TiO2 solutions were prepared by an improved thermal hydrolysis method. The optical fibers with the diameter of 0.1mm were coated by the dip-coating method. From the SEM micrographs, the catalyst layer had thickness about 30nm comprising fine spherical particles, which had diameter of 10-20nm and nano cavities between the crystallites. The XRD spectra showed all M(Cu, Ag, Pt)/TiO2 had anatase phase. From the UV-Vis spectra, the wavelength of absorption edge was near 350nm. The results of the XPS spectra revealed that Cu, Ag and Pt in the forms of Cu+, Ag0, Pt2+ or Pt4+ existed on TiO2 surface, respectively. The methanol yield increased with increasing UV irradiative intensity. The main product was methanol and other few products were formic acid and methyl formate. The loaded transition-metals (Cu, Ag, Pt) efficiently enhanced the methanol yield.

並列關鍵字

Photocatalytic reduction ； Optical-fiber reactor ； CO2 ； TiO2

參考文獻

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