鉭金屬焦綠石的合成與在光致發光及光催化產氫反應之研究

Tantalum-Based Pyrochlores: Synthesis and Applications: for Photoluminescence and Photocatalytic Hydrogen Production

吳冠璋

指導教授 ： 楊家銘

國立清華大學/理學院/化學系/碩士(2012年)

摘要

本論文利用檸檬酸鹽-溶膠法搭配水熱法合成鉭金屬焦綠石結構的合成K1-2XMTa2O7-X (M = Gd、In)並且成功置換不同的金屬x離子於結構中，並且以XRD、UV、SEM/EDX、XPS研究對其樣品的結構與成分的分析與鑑定。其中K1-2XGdTa2O7-X在摻雜Eu以後可以出紅光並且藉由調控合成天數、Eu的量、KOH的量、鍛燒、還原，最佳化樣品光致發光強度，並且製成元件。另外K1-2XInTa2O7-X在光催化產氫方面最佳活性的產氫量分別為全分解1800.00 μmol g -1 h-1與使用犧牲試劑5833.30 μmol g -1 h-1並且藉由調控合成溫度、使用鹼的種類、鍛燒、酸處理，研究光催化的活性。

關鍵字

水分解 ； 光催化反應 ； 焦綠石 ； 水熱法

並列摘要

Abstract
Tantalate pyrochlore, K1-2XMTa2O7-X (M = Gd、In、Ce), was successfully synthesized by citrate sol-gel and hydrothermal method. The most important thing is that pyrochlore phase would not be transformed by replacing different metals.
Tantalate pyrochlore was applied in photoluminescence. The devices with optimal intensity of photoluminescence were determined by duration of synthesizing, the concentration of potassium hydroxide, the level of calcinations and reduction.
In this research, tantalate pyrochlore was also applied in photocatalyst, especially hydrogen production. The activity of photocatalysis was indicated by temperature of reaction, the type of bases, the level of calcinations and acid treatment. Tantakate pyrochlore, whose amount of hydrogen production is 1530 μmol g-1 h-1, with highest activity of photocatalysis was fabricated under NH3 solution. If sacrificial reagent was used under ammonium condition, the amount of hydrogen production was up to 2606.36 μmol g-1 h-1. Moreover, if tantalate was treated with potassium hydroxide, the activity of photocatalysis was higher than ammonium-treated tantalate. And the hydrogen production was 1800.00 μmol g-1 h-1. When sacrificial reagent was added in the process of synthesizing tantalate, the amount of hydrogen production was up to 5833.30 μmol g-1 h-1.

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