奈米相氧化鋅錫光觸媒特性之研究

The Study on Photocatalytic Characterization of ZnO-SnO2 Nanophases

潘筱盈(Xiao-Ying Pan)

指導教授 ： 蔡木村

國立虎尾科技大學/工程學院/材料科學與綠色能源工程研究所/碩士(2010年)

摘要

本研究是以溶膠凝膠法製備氧化鋅錫奈米粉體，並探討不同摻雜劑對sol-gel反應、相結構、微結構及光催化反應之影響。
經由摻入不同的離子劑量及添加適量溶劑，可得到清澈之溶膠與透明之凝膠。經400~600 oC熱處理可製得氧化鋅錫(ZnO:χSnO2; χ = 0.5~10莫耳比)奈米相粉體，結構分析顯示，具有氧化鋅及二氧化錫之雙相結晶。隨著溫度增加，氧化鋅及二氧化錫之結晶性均有明顯變強；顆粒隨著溫度上升由球狀顆粒轉變為條狀型態，且有明顯粗化的現象。熱處理溫度為400 oC下，隨著二氧化錫劑量的增加，氧化鋅錫奈米粉體之粒徑呈逐漸細化的現象，平均粒徑約為10~12 nm，粉末型態仍繼續維持為球狀顆粒，結構顯示均為奈米微粒子結構。
實驗發現，氧化鋅錫奈米相粉體經由紫外光照射1.5小時後，可達到60 %的MO染劑去除率，而藉由摻雜不同離子，可使降解效率提升至97~99 %。此外，利用本實驗製備出之氧化鋅錫粉體經由紫外光照射1小時後，即可達到88~98 %的AO7染劑去除率。光降解反應結果顯示，製程參數、能隙值及電子電洞對的再結合等因素，皆會影響降解的效率。

關鍵字

氧化鋅錫 ； 光觸媒 ； 溶膠凝膠法 ； 酸性橙色7號 ； 甲基橙

並列摘要

In this study, nanophases zinc and tin oxides were prepared by the sol-gel process. The effects of various dopants on the sol-gel reaction, phase structure, microstructure and photodegradation property were investigated.
Clear sols were formed by adding various ions. Transparent gels could be obtained by adding proper solvents. Nanophases zinc and tin oxides (ZnO:χSnO2 ; χ = 0.5~10 molar ratio) were formed after heat-treatments at 400~600 oC. The crystallinities of zinc and tin oxides were remarkable increase with temperature. With increasing temperature, the nanoparticle sizes were obviously increase and transfer to nanorod morphologies. Nanoparticle sizes decreased with increasing the amount of tin oxide. After firing at 400 oC, the powders has granular morphology with average grain sizes about 10~12 nm.
Photodegradation of methyl orange (MO) showed the degradation rate reach to 60 % under UV-light irradiation. With doping different ions the degradation rate could improve to 97~99 %. In addition, photodegradation of AO7 (Acid Orange 7) showed the degradation rate reach to 88~98% under UV-light irradiation. Photodegradation analysis showed the relative degradation depended on the process parameters, energy gap and electron-hole recombination rate.

並列關鍵字

zinc and tin oxides ； Photocatalytic ； sol gel ； AO7 ； MO

參考文獻

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