以三嵌段兩性共聚物輔助溶膠-凝膠法製備介孔二氧化錫

Preparation and Characterization of mesoporous SnO2 with a Sol-gel Method

潘艾倩(PAN AI CHIEN)

指導教授 ： 張莉毓

國立屏東科技大學/工學院/機械工程系所/碩士(2009年)

https://doi.org/10.6346/NPUST.2009.00269

摘要

介孔材料由於具有高比表面積及孔洞分佈均勻之特性，其應用相當廣泛，是近年來在奈米材料科學領域中引人注目的研究領域。本研究利用三嵌段兩性共聚物作為天然模板，SnCl4‧5H2O為反應前驅物，以溶膠-凝膠法製備高比表面積的介孔二氧化錫。經 TGA, X-ray, SEM, FTIR, TEM 和BET 分析材料微結構，並探討三嵌段兩性共聚物的添加量、NH4OH添加量和加水反應於不同煆燒溫度下之結構變化。
實驗結果顯示，利用溶膠-凝膠法，以三嵌段兩性共聚物為天然的模板，煆燒溫度300 ~ 500 °C，均合成具有cassiterite相之介孔二氧化錫。使用三嵌段兩性共聚物的添加量為 1.5 g，煆燒溫度 300 ℃，可合成出最大比表面積約為188 m2/g、孔洞直徑約為40.77 Å；三嵌段兩性共聚物添加量對試樣介孔結構影響甚大，當添加量從0.1改變至1.5 g時，其比表面積會從121.49增加至188 m2/g。
此外，在反應系統中NH4OH和水的含量亦會影響二氧化錫之介孔結構。三嵌段兩性共聚物的添加量為1.0 g，以NH4OH取代酒精含量為25 %，煆燒溫度在400 ℃時，可合成出比表面積約為122.31 m2/g、孔洞直徑約為27.14 Å之介孔二氧化錫。而以水取代酒精含量為25 %，煆燒溫度在300 ℃時，可合成出比表面積約為207.99 m2/g、孔洞直徑約為89.97 Å之介孔二氧化錫。

關鍵字

介孔二氧化錫 ； 溶膠-凝膠法 ； 三嵌段兩性共聚物 ； 比表面積

並列摘要

Recently, mesostructured materials with high surface areas and large pore sizes have attracted much attention because of their potential applications. In this study, mesoporous SnO2 was prepared by sol-gel process and the synthesis was accomplished by using triblock copolymer as the template, and SnCl4‧5H2O as the inorganic precursor. The effects of triblock copolymer additives, NH4OH additives, water and calcining temperatures on the structure of mesoporous SnO2 were investigated by TGA, X-ray, SEM, FTIR, TEM and BET analyses.
Using triblock copolymer as the template, mesoporous SnO2 with the cassiterite structure were obtained at 300~500°C. Mesoporous SnO2 exhibits a high specific surface area of 188 m2/g, and an average pore size of 40.77 Å for 300℃ calcination and using 1.5 g triblock copolymer. The mesostructure of SnO2 can be controlled by the addition of triblock copolymer. When the addition of triblock copolymer increased from 0.1 to 1.5 g, the specific surface areas increased from 121.49 to 188 m2/g after being calcined at 300℃.
The NH4OH and water content in the reaction system are believed to determine the microstructure formation. The mesoporous SnO2 was shown to have a specific surface area of 122.31 m2/g and the average pore diameter was 27.14 Å after it was calcined at 400 °C when the ethanol solvent was replaced with 25% NH4OH using 1.0 g triblock copolymer. The result also showed that mesoporous SnO2 prepared with 25 % replacement of water and calcined at 300°C exhibited a specific surface area of 207.99 m2/g and an average pore size of 89.97 Å.

並列關鍵字

mesoporous SnO2 ； sol-gel method ； triblock copolymer ； specific

參考文獻

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