微波水熱法製備二氧化鈦及其光催化之研究

Synthesis and Photocatalytic Effect of Microwave Hydrothermal Derived TiO2 Powders

羅國彰(Kao-Zhang Lo)

指導教授 ： 王宏文

中原大學/理學院/化學系/碩士(2007年)

https://doi.org/10.6840/cycu200700381

摘要

二氧化鈦因價格低廉、取得容易、材料特性穩定等因素，為近年來常被研究用來製作光觸媒及太陽能電池的半導體材料。本研究主題便是以Titanium (IV) isopropoxide,二氧化鈦金屬前驅物以sol-gel法製備溶液，分別探討微波水熱及傳統y燒，比較兩種不同結晶相的生成方式對光催化的影響。
首先，微波水熱法在110℃與10min條件下，以XRD繞射分析後，即可得知有Anatase相生成，其粒徑大小約20nm，測得比表面積高達185 m2/g以上。另一方面，經y燒後的二氧化鈦，隨著y燒溫度的提高，粒徑開始聚集成長，比表面面積也由118m2/g降至22m2/g。
在分別以UV鑑定其光催化能力，結果y燒500℃的二氧化鈦，經過60min的UV照射下，對10-5M濃度下的亞甲基藍試液分解率達59.2﹪，優於P-25 41.6﹪的分解率；至於微波水熱法，在本研究170℃/180min的最佳條件下，對亞甲基藍試液的分解率僅達8﹪，其分解率能力等同於傳統y燒400℃/60min下結果，推斷其光催化效果不彰的原因，可能為Anatase生成相較低，導致微波水熱法製備之二氧化鈦無法對亞甲基藍試液產生顯著的分解能力。

關鍵字

微波水熱法 ； 光催化 ； 二氧化鈦

並列摘要

Titanium dioxide (TiO2) has been widely used as the raw material for making solar cells due to its photocatalytic characteristics, low cost, easily accessible, and stability. In this study, TiO2 was synthesized by the sol-gel method using TTIP as the precursor. The crystalline phase of TiO2 synthesized using microwave and conventional hydrothermal were investigated and compared in terms of their photocatalytic performances.

Anatase TiO2 was formed using microwave at 110℃/10min. Diameter of particles is approximately 20 nm and specific surface area is greater than 185m2/g. On the other hand, the TiO2 formed using conventional hydrothermal depends largely on the temperature. As the hydrothermal temperature increases, the particle size increases. For instance, the specific surface area of TiO2 is reduced from 118m2/g to 22m2/g at high temperatures.

The photodegradation efficiency of TiO2 calcined at 500℃ for 10-5M of methylene blue is 59.2% under 60 minutes of UV irradiation, which is better than that of P-25 (41.6%). For those obtained using microwave method at 170℃/180min, its photodegradation efficiency for methylene blue is only 8%, which is equivalent to that of the TiO2 calcined at 400℃/60min. The unsatisfied photodegradation efficiency is rationalized by the low anatase TiO2 obtained by microwave hydrothermal, which consequently reduces the photocatalytic performance of TiO2

並列關鍵字

Microwave Hydrothermal Derived ； Photocatalytic Effect ； TiO2

參考文獻

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