二氧化鈦具有良好的光催化特性與穩定性已廣泛運用於觸媒及於光水解電極，其中又以奈米結構因在水分解中具有明顯的效率改善。本文將利用水熱法於高摻雜負型矽基板以及導電玻璃FTO上生成二氧化鈦奈米柱，並對其水分解能力特性進行量測以及表面形貌變化的觀察。主要探討退火溫度、以及二氧化鈦奈米柱之形貌以及長度對照光水分解的影響。研究利用濺鍍法於基板表面濺鍍鈦金屬層，經由熱氧化使表面具有二氧化鈦晶種層，將有助於不同基板上利用水熱法成長二氧化鈦。

The Rutile nanorods (NRs) TiO2 for water splitting applications were prepared on Si, FTO, and silicon nanowires array (SiNWs) by hydrothermal method. A three-electrode system and solar simulator were used to measure the photocurrent of water splitting. In order to investigate the relationship between the morphologies of TiO¬2nanorods and the photo currents during bias, difference hydrothermal temperatures, precursor compositions, synthesized times, and various annealing conditions were performed. The currents of theTiO2NRs grown on FTO were optimized. Unfortunately, whenTiO2 NRs prepared on Silicon and SiNWs as the substrate, forming a three dimensional TiO2 structure, the negligible photocurrent were measured. To understand the reason of the current decrease, Mott-Schottky measurement and X-ray photoelectron spectroscopy (XPS) were used to show that at the interface of silicon and TiO2 the titanium did not complete oxidized. Instead of Ti film fully oxidized, silicon substrate was oxidized in the afterward annealing stage.

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