二氧化鈦奈米管負載銀與氫化處理之光催化應用

Abstract

本實驗利用兩次電化學陽極處理，以高純度的純鈦片做為基材製備出高品質的二氧化鈦奈米管，分別使用光沉積法負載金屬銀和氫化處理等改質方式改善光電轉換效率。 以SEM/EDS 觀察表面形貌、X-ray分析二氧化鈦的晶體結構和XPS分析表面化學鍵結，更運用同步輻射中心(NSRRC)光束線17B和24分析負載金屬銀的二氧化鈦奈米管，以AM1.5太陽光模擬器做為光源，量測光電流密度和光電轉換效率並加以討論。 相較未改質的二氧化鈦奈米管，經過負載銀和氫化處理皆可以提升光電流密度和光電轉換效率，其中以二階陽極處理負載銀達到光電流密度0.52 mA/cm2 和光電轉換效率 0.64%表現較佳，而經過氫化處理後可以達到光電流密度0.79 mA/cm2 和光電轉換效率 0.87%，相較改質前整體表現提升了2.07倍為本研究最佳參數，本研究將會探討負載銀和氫化處理對二氧化鈦奈米管之光催化影響。

Highly ordered TiO2 nanotube arrays are fabricated via electrochemical anodization of high purity titanium metal sheet in fluorine containing electrolytes. The microstructures were characterized by GIXRD, XPS, SEM, synchrotron radiation beam line 17B and beam line 24 analyses. Using a solar simulator measurement, the photocurrent density and photoelectric conversion of the TiO2 nanotubes was evaluated and discussed. The photoconversion efficiency of silver loading TiO2 nanotubes following hydrogenation treatment at 300°C for 3hs was found to be improved comparing with the highly ordered TiO2 nanotubes arrays. With silver loading, the TiO2 nanotubes can achieve 0.64% in efficiency with 0.52 mA/cm2 in photocurrent density for hydrogen production; after the hydrogenation treatment, the efficiency and photocurrent density increase to 0.87% and 0.79 mA/cm2, respectively. The efficiency of the silver-loaded TiO2 nanotubes and hydrogenation treatment also will be discussed.