一維奈米結構對於電子的傳遞較容易且快速，因而發展許多一維奈米結構材料應用於各種領域。其中，二氧化錫半導體是一種關鍵材料，已被廣泛地用於光電子材料設備和傳感器。SnO2本身導電性差，常藉由還原或摻雜不同原子以提高載子濃度並提升電性質，其中最典型且具有發展潛力的F:SnO2 (FTO) 導電材料已廣泛使用在各種光伏元件。本研究為了縮短電子傳遞的路徑，對FTO導電玻璃進行表面修飾。目的為成長垂直規則之FTO結構於2-D平面上，延伸成3-D結構的導電基材，增加其表面積與粗糙程度，有效提升其相關應用。
本研究第一部分使用相對低溫的熱蒸發氣相沉積法 (VS)，成功製備一維SnO2奈米柱與F：SnO2於FTO基板上。討論不同NH4F／SnCl2‧2H2O比例下所合成之FTO結構於染料敏化太陽能電池之效率表現。其中以Ratio=0.5的摻雜條件下，光電轉換效率6.19 % 相較於對照組市售FTO (5.52%)有12%的提升。貢獻來自於一維FTO與光陽極間的良好接觸，兩者間接觸電阻 (Rco)較小，反映出較大的填充因子FF與較小的R1 (3.72 Ω)。由於交錯的FTO錐狀結構，導致入射到元件內部的光線被散射，理論上將有益於光線捕捉。但整體而言，電流密度之表現沒有提升，無法彰顯一維FTO結構的貢獻，此原因需進一步討論。
第二部分則使用氣相沉積法中VLS成長機制。濺鍍金觸媒於FTO基材上，並於管狀高溫爐中通入適量N2與Air，搭配NH4F做為摻雜氟來源，成功以單步驟製備一維FTO奈米線。根據不同沉積長度一維FTO奈米線基材之片電阻值及親水性的表現，顯示此基材對於液態感測器之應用極具發展潛力，如H2O2之感測。對照組市售FTO受限於較差之親水性使其鉑金屬附著量少，影響其感測H2O2靈敏度，與最高靈敏度271.52 mA / M之Au-FTO NWs-3hr基材效果相差約100倍，差異懸殊。貢獻來自於一維FTO奈米線增加鉑金屬之負載，而顯著地提升其靈敏度。本研究提供良好導電性、高表面積與親水性之新型感測器電極材料。

One-dimensional nanostructure is much easily and quickly for electron transfer, therefore many kinds of one dimensional structural materials were developed and used in various fields. Semiconducting SnO2 is a key functional material that has been used extensively for optoelectronic devices and sensors. Because the conductivity of SnO2 is not notable, SnO2 often doped with different atoms in order to improve and enhance the carrier concentration and electrical properties. FTO, fluorine-doped tin oxide, because of its excellent visible light transparency and electric conductivity, has found extensive applications in optoelectronics, display, and photovoltaic devices as a transparent conductive electrode. In this study, we aim to alter the 2-D flat FTO film to fabricate an extended 3-D FTO structure, to increas its surface areas and roughnesses, and effectively shorten the path of electron transfer.
In the first part of this study, we developed a vapor-solid (VS) process, to successfully grow 1-D nanocone FTO on commercial FTO substrates for applications in dye-sensitized solar cells (DSSC) as the anode substrate. Through the investigation of the effect of the NH4F／SnCl2‧2H2O ratio in the anode substrate fabrication, we found that the power conversion efficiency (PCE) of the DSSC changed accordingly. When the doping ratio was 0.5, the PCE was slightly enhanced to 6.19 %. As compared with the PEC obtained by using commercial FTO as the anode substrate (5.52 %), the PCE has increased 12%. The good contact between the TiO¬2 and the present 1-D FTO anode substrate led to smaller contact resistances (Rco). This further resulted in a large fill factor of 0.74 and small R1 of 3.72 Ω.
In the second part, we developed a vapor-liquid-solid (VLS) process, employing gold nanoparticles as the catalyst, to grow FTO nanowires on commercial FTO substrate. These 1-D FTO structure samples were prepared inside a quartz tube, with flowing N2 and air to adjust oxygen concentration for SnO2 nanowire formation and NH4F as the fluorine source for in-situ F-doping. The products showed low sheet resistances and high hydrophilicity, and thus possessed a great potential for applications in H2O2 sensing through Pt-loading. Because of the poor hydrophilicity of the commercial FTO, the amount of Pt loading was limited, which affected its sensing performance. The nanowire length of sample Au-FTO NWs-3hr was about 750 nm, and was good for Pt loading. This sample showed a high sensitivity of 272 mA/M. This study successfully develops a promising and novel sensing electrode, which is conducting, of high surface area, and highly hydrophilic.

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