本研究係利用溶膠-凝膠法(sol-gel method)製備氧化鋅錫鋁(ZnO/SnO2/Al)複合相奈米粉體,並探討不同化學組成、熱處理溫度、摻雜濃度、染劑酸鹼值及照射光源對粉體結構、微結構及光催化反應之影響。粉體特性是分別利用熱重/熱差分析儀(TGA/DTA)、X光繞射儀(XRD)、傅立葉轉換式紅外線光譜儀(FT-IR)、場發射掃描式電子顯微鏡(FE-SEM)、元素分析儀(EA)、氮氣吸脫附量測及紫外光/可見光分光光度計(UV-Vis)檢測。 結果顯示經熱處理400~600 oC可形成氧化鋅錫(ZnO/SnO2)複合相奈米顆粒,於熱處理650 oC以上,會開始產生錫酸鋅(ZnSnO3或Zn2SnO4)結晶相,且鋅錫比及熱處理溫度會影響粉末結晶性及微結構。光催化偶氮染料(AO7/MO)顯示,於適當的成份比例、熱處理溫度、溶液條件及摻雜適量金屬離子可有效促進光觸媒活性及降解效率。
In this study, nanosized ZnO/SnO2/Al composites nanoparticles were prepared by the sol-gel method. Effects of chemical composition (Zn/Sn ratio), heat-treatment temperature, doping concentration, pH values of dye solution, and irradiation light source on the structure, microstructure, and photocatalytic reaction were investigated. The powder samples were characterized by thermogravimetric and differential thermal analyzer (TGA/DTA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscope (FE-SEM), N2 adsorption-desorption measurement, elemental analysis (EA), and ultraviolet/visible spectrometry (UV-Vis). The experimental results showed that the composite nanoparticles with coupled phases of zinc oxide and tin oxide (ZnO/SnO2) can be formed after heating at 400~600 oC. On heating at above 650 oC, zinc stannate phase such as ZnSnO3 or Zn2SnO4 started to form. The crystallility and microstructure of the powders were dependent on the various Zn/Sn ratio and heat-treatment temperature. Photocatalytic degradation of azo dyes (AO7/MO) revealed that the photocatalytic activity and degradation efficiency could be enhanced with proper composition, heat-treatment temperature, solution condition and dopant content.