本實驗透過對氧化鋅光觸媒的改質，來提升光催化降解汙染物的能力，藉由摻雜銅進入氧化鋅晶格的方式改變氧化鋅的能帶間隙以及光吸收能力，同時也藉由添加石墨稀並附著於氧化鋅表面去改善電子電洞的再結合速率。本實驗使用微波水熱法製備含有石墨稀的銅摻雜氧化鋅粉末，使用的前驅物包含醋酸鋅、醋酸銅、以及實驗室自製的氧化石墨稀。藉由調整醋酸鋅的濃度和水熱法時的溫度及時間來找到降解效果最好的純氧化鋅，再使用該參數來製備銅摻雜氧化鋅及含石墨稀之銅摻雜氧化鋅，然後分別比較銅摻雜及石墨稀添加的濃度對光催化之影響。
實驗使用X射線繞射儀和掃描式電子顯微鏡去分析其晶體結構和表面形貌，使用表面吸附儀測量改質的氧化鋅比表面積，表面化學鍵結分析確認是否具有銅摻雜進入氧化鋅晶格以及氧化石墨稀還原程度，光學性質分析方面，使用可見光/紫外光光譜儀量測改質的氧化鋅的光吸收能力，使用光激發光分析電子電洞再結合速率。最後透過使用可見光或紫外光分解亞甲基藍，來測試改質後氧化鋅的光催化分解汙染物之能力。

We report a novel Cu-doped ZnO/RGO nanocomposite photocatalyst that exist enhanced efficiency. Nanostructured Cu-doped ZnO/RGO was synthesized in one step by using a hydrothermal method. The hydrothermal bath consisted of zinc acetate dehydrate as zinc precursor, sodium hydroxide, distilled water, copper acetate dehydrate for copper precursor and with or without the addition of GO. The material characteristics of the obtained nanocomposite samples were characterized using X-ray diffraction, Scanning-electron microscopy, Brunauer–Emmett–Teller, X-ray photoelectron spectroscopy, UV-visible spectroscopy, Raman spectroscopy and Photoluminescence. The photocatalytic efficiency was evaluated through the degradation of methylene blue under UV and visible light. Effect of materials characteristics on the photocatalyst behavior is addressed and discussed.

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