奈米結構的物質因為他們擁有獨特的特性，因此近年來被廣泛的討論。其中的特性是奈米纖維擁有較大的比表面積，因此在本實驗中，試著使用不同比例的鈦金屬與銅，以簡單和低成本的方法，利用電紡絲製備出鈦銅奈米纖維，並在空氣中進行鍛燒，而鈦銅奈米纖維的特徵是藉由感應偶和電漿原子發射光譜 (ICP-AES)、場發式電子顯微鏡 (FE-SEM)和X射線照射分析 (XRD)去進行分析，最後再進一步利用UV光放射催化將4-硝基苯酚轉換成4-氨基苯酚。
本實驗鍛燒的溫度在光轉換過程中占很重要的角色，而最佳的鍛燒溫度是設定在攝氏400℃，當鍛燒溫度升高超過400℃時，會產生較慢的催化活性；反之當溫度在400℃以下時，纖維結構還是屬於非晶狀。另一個有趣的發現是，當氧化銅 (CuO)被還原成銅 (Cu(0))時，反應速率會受影響而提升，而將氧化銅還原成銅的方法是將鈦銅奈米纖維浸泡在硼氫化鈉 (NaBH4)溶劑中，其中Ti/Cu(5.6)-400在進行氧化銅還原時，反應速率會從0.766提升到2.413 mmol g¬-1 min-1。本實驗結果顯現了非貴金屬觸媒對4-硝基苯酚轉化成4-氨基苯酚有良好的催化性質，可取代現在的貴重金屬觸媒。

Keywords：電紡絲；纖維；合成；鈦金屬；銅；觸媒；4-氨基苯酚

Nano-architecture materials such as nanofibers are extensively studied due to their unique characteristic such as large surface area. Here, in this study composite titanium-copper fibers with different titanium to copper ratio were fabricated by a simple and low cost method of electrospinning followed with calcinations in air. The resulted fibers were characterized by inductive coupled plasma atomic emission spectra (ICP-AES), field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and further utilized as photocatalyst for conversion of 4-nitrophenol to 4-aminophenol under UV irradiation.
This study revealed calcination temperature played an important role on the photoconversion process, with the optimum calcination temperature was 400°C. Further increasing the calcination temperature beyond 400°C generated slower catalytic activity, while below 400°C the fibers were still amorphous. Another interesting finding was, by reducing the copper oxidation state, from CuO to Cu(0), a faster rate constant can be achieved. The rate constant was significantly increase from 0.776 to 2.413 mmol g-1 min-1 after reducing the copper oxidation state in Ti/Cu(5.6)-400 sample. The reduction of CuO to Cu(0) itself was done by immersing the composite titanium-copper fibers into NaBH4 solution. Therefore, this work demonstrated a non-noble metal catalyst with promising catalytic activity toward conversion of 4-nitrophenol to 4-aminophenol, to substitute the utilization of expensive noble metal in the present catalyst.

Keywords: Electrospinning; fibers; composite; titanium; copper; catalyst; 4-nitrophenol.

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