二氧化鈦奈米管陣列開孔方向對於染料敏化太陽能電池之影響

Opening direction of TiO2 nanotube arrays for Dye-Sensitized Solar Cells

許淨雯(Ching-Wen Hsu)

指導教授 ： 蘇昭瑾

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2012年)

https://doi.org/10.6841/NTUT.2012.00038

摘要

本實驗分為二部分，前期以陽極氧化法製備銳鈦礦相二氧化鈦奈米管陣列，探討以不同陽極氧化時間處理，及經450 oC鍛燒後奈米管變化之情形。進行第二次陽極氧化搭配改變電壓方式，得到管底封閉的單開孔二氧化鈦奈米管陣列自由立膜，以及管底開孔的雙開孔二氧化鈦奈米管陣列自由立膜。使用本實驗室製備的二氧化鈦奈米顆粒漿料為黏著劑，將二氧化鈦奈米管陣列自由立膜以不同開孔方向，張貼於Fluorine-doped tin oxide (FTO)導電玻璃上，並封裝為染料敏化太陽能電池。

本實驗第一部分，經由第二次陽極氧化法及降低電壓方式，製得管底封閉的單開孔二氧化鈦奈米管陣列自由立膜，張貼自由立膜於FTO導電玻璃，開孔朝向對電極命名為正開孔、開孔朝向FTO導電玻璃為背開孔。不同開孔方向會影響電子傳輸，且影響光電轉換效率。測量後得知背開孔效率為6.93 %、正開孔為5.65 %；在530 nm波長下，背開孔入射單色光子-電子轉化效率為42.21 %、正開孔入射單色光子-電子轉化效率為46.35 %。

本實驗第二部分，經由第二次陽極氧化法及提高電壓方式，製得管底開孔的雙開孔二氧化鈦奈米管陣列自由立膜。由於兩端為開孔，探討雙開孔結構對於染料吸附量的變化，並在模擬太陽光量測的光源照射下，測量電子在二氧化鈦奈米管陣列自由立膜與電極之間的傳遞狀態。測量得之雙開孔效率為6.42 %；在530 nm波長下，雙開孔入射單色光子-電子轉化效率為47.63 %。

總結兩部分探討的結果，以不同開孔方向的二氧化鈦奈米管陣列自由立膜，張貼於FTO導電玻璃上，所封裝出三系列分別為正開孔、背開孔及雙開孔染料敏化太陽能電池，測量出三者之間的光電特性。效率以背開孔效率6.93 %為最佳，入射單色光子-電子轉化效率以雙開孔47.63 %為最佳。

關鍵字

二次陽極氧化法 ； 二氧化鈦奈米管陣列 ； 正開孔 ； 背開孔 ； 雙開孔 ； 染料敏化太陽能電池

並列摘要

The aim of this thesis is to fabricate a TiO2 nanotube based dye-sensitized solar cells (DSSCs) with the front-side illumination. In this work, the formation of ordered anatase TiO2 nanotube (TNT) arrays was carried out by potentiostatic anodization process followed by annealing at 450 oC for particular time. Subsequently, tube-shaped and pipe-shaped free standing TNT arrays were fabricated by voltage-pulse method, in which voltage pulses were applied for a short time at the end of the anodization process. The TNT arrays were detached and transferred onto the FTO substrate using TiO2 NP paste as an interface and used as a photoanode in DSSCs for front-side illumination.

The first part of this work is the preparation of tube-shaped TNT arrays by varying the second anodization voltage. The free-standing TNT arrays were attached on the FTO substrate in two directions, one as upright (face-up) and another one is inverted (bottom-up). In order to investigate the effect of TNT array direction in DSSCs performance, the characteristics analysis of N719-based DSSCs, such as current density-voltage (J-V) and incident photo-to-current conversion efficiency (IPCE) measurements were performed.

The second part of this work is the preparation of pipe-shaped TNT arrays by elevating the anodizing voltage at the end of second anodization process. Elevating the voltage helps to break the adhesion of the TNT arrays from the underlying Ti substrate and simultaneously open their closed bottom. Adsorption of N719 dye for the closed bottom and opened bottom TNT array photoanodes were studied. The photoelectrical performance of DSSCs with closed bottoms and opened bottoms TNT arrays were investigated and compared with each other.

Hereby, from the above two works we can conclude that the front-side illuminated TNT arrays based DSSCs demonstrated a better improvement in the photoconversion efficiency. The free-standing TNT arrays were attached on the FTO substrate in three directions, one as upright (face-up), another is inverted (bottom-up), and the other is open-end. In order to investigate the effect of TNT array direction in DSSCs performance, inverted (bottom-up) has the best efficiency is 6.93 %. And incident photo-to-current conversion efficiency (IPCE) measurements were 47.63 % at 530 nm wavelength in open-end.

並列關鍵字

Anodization ； TiO2 nanotube arrays ； Face-up ； Bottom-up ； Open-end ； Dye-sensitized solar cells

參考文獻

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