分離式二氧化鈦奈米管在染料敏化太陽能電池之運用

Fabrication of Separated TiO2 Nanotubes and Application of Dye-Sensitized Solar Cell

吳勇蒼(Yung-tsang Wu)

指導教授 ： 陳昇暉 ； 張瑞芬

國立中央大學/理學院/照明與顯示科技研究所/碩士(2014年)

摘要

現今主流的染料敏化太陽能電池(Dye-sensitized Solar Cell, DSSC)工作電極為奈米顆粒(TiO2 nanoparticles, TNP)，但由於奈米顆粒的介面使電子具非單一路徑傳輸並且增加其復合機率。故本研究以陽極氧化鋁(Anodic Aluminum Oxide, AAO)方式製作出奈米孔洞模板，再利用原子層沉積(Atomic Layer Deposition, ALD)技術、高密度電漿蝕刻(High Density Plasma Etch, HDP)及化學濕蝕刻方式製作分離式二氧化鈦奈米管(TiO2 nanotubes, TNT)，作為染料敏化太陽能電池的工作電極，使電子具單一性方向傳遞並減少介面間缺陷的復合機率，提升光電轉換效率(Power Conversion Efficiency, PCE)。
而以二次陽極氧化鋁方式可製作出規則性及周期性較好且真圓度大於0.8的奈米管，且在不同基板可製作出不同晶相之二氧化鈦奈米管，最後再浸泡六甲基二矽氮烷(Hexmethyldisilane, HMDS)處理，可使分離式二氧化鈦奈米管在乾燥的過程中不會因內聚力倒塌並形成區塊的破碎。本研究製作的分離式二氧化鈦奈米管管壁厚度為20 nm，平均週期為93.5 nm ~ 202.5 nm，管長300 nm ~ 5.1 μm。而光電轉換效率高於奈米顆粒工作電極，可達1.432%。

關鍵字

染料敏化太陽能電池 ； 奈米管 ； 二氧化鈦 ； 陽極氧化鋁 ； 原子層沉積

並列摘要

TiO2 nanoparticle (TNP) is one of the most popular materials to be the working electrode for dye-sensitized solar cells (DSSCs). However, the carriers are recombined frequently when they propagate to the interface of the TNP. In other word, this is one of the significant issues to decrease the power conversion efficiency (PCE) of a DSSC. In this study, we proposed a TiO2 nanotubes (TNT) as the working electrode for the DSSC. The TNT was fabricated by using atomic layer deposition (ALD) technique on an anodic aluminum oxide (AAO) template. Then we used high density plasma (HDP) etching and wet etching to remove the AAO template. The TNT can help the carriers to propagate in a single-path which can decrease the carrier recombination.
We fabricated the TNTs with better regularity and circularity more than 0.8 by using 2-step AAO method. And the TNTs were fabricated with different crystalline structures on the different substrates. Then, we immersed the TNTs in Hexmethyldisilane (HMDS) to prevent the TNTs to be broken by cohesion. In our research, the thickness of the TNT is 20 nm when period is in the range from 93.5 nm to 202.5 nm. The length of TNT was varied from 300 nm to 5.1 μm. Finally, we demonstrate a DSSC with TNT electrode is better than the DSSC with TNP electrode in PCE is 1.432%.

並列關鍵字

dye-sensitized solar cell (DSSC) ； nanotube ； TiO2 ； anodic aluminum oxide (AAO) ； atomic layer deposition (ALD)

參考文獻

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