功能化二氧化鈦奈米管陣列的基礎研究與應用

Abstract

由於全球性的能源危機以及台灣環保意識的高漲，在這個兩年期的國科會個人 計畫中我們提出一個以低成本開發高效能染料敏化太陽能電池(DSSC)的方法。我們 的核心技術是利用電化學陽極處理的方法直接在鈦薄板上製備大面積的功能性二氧 化鈦奈米管陣列(ATO nanotube array)薄膜，其具有高表面積及可調控的特性故可 在吸附光敏染料後作為DSSC 的陽極，以取代傳統以導電玻璃及TiO2 奈米顆粒為陽 極的Gratzel cell。在計畫執行的第一年中，我們將利用不同奈米製程如陽極處理 法與溶膠-凝膠法來製作高品質之奈米級二氧化鈦材料，再針對不同的實驗參數對二 氧化鈦的表面型態、結晶特性、光譜及光電特性等深入探討，並將ATO 奈米管應用 於表面的自我清潔。第二年我們將利用第一年所製得之材料應用到DSSC 之元件封裝 與光電流量測，改變的參數包括了ATO 奈米管的孔徑大小、管子的長短、不同染料 與電解質的影響，並利用超快光譜技術來研究電子與電洞在染料與奈米管界面間傳 遞的動力行為。我們所提出的奈米管DSSC 將具有低成本、可撓曲、大面積、可回收 再使用等特性，若能提高光電轉換效率與增長使用壽命，其發展潛力將無可限量！

Due to the global energy crisis and the sense of environmental protection in Taiwan, in this two-year proposal we propose a method to develop dye-sensitized solar cell (DSSC) with the possibility of low cost and high efficiency. Our core technology is to make large-area anodic TiO2 (ATO) nanotube array directly on the surface of Ti-foil utilizing the method of anodization. After sensitized with organic dye molecules, the dye/ATO thin-films can be used as anode to replace the traditional TiO2 nanoparticle-based films used in Gratzel cell. For the first year, we will make high-quality TiO2 nanostructures using both anodization and sol-gel methods. The structure and morphology of the TiO2 surface will be investigated using XRD, SEM and TEM; the spectral and photocurrent measurements (IPCE) will be performed to study the opto-electric properties of the material. The ATO nanotube array can be applied to the field of self-cleaning of surface. For the second year, we will fabricate DSSC using the ATO nanotube array material optimized in the first year. Both IV curve and IPCE measurements will be carried out in order to find the best condition of the cell; the variables to be tested include the pore size and the length of the tubes, different dye molecules (including Ru-complexes and porphyrins), and different composition of the electrolytes. We will also study the relaxation dynamics of the electron-hole pair for the key transport process in the interface between the dye molecules and the TiO2 nanostructures using ultrafast spectroscopy methods established in our laboratory. Our goal is to find the best ATO-DSSC with the advantage of low cost, flexibility, large area and reusability. We might provide an economical solution for the problem of the global energy crisis if we succeed in promoting the efficiency of the cell and improving the lifetime of the cell.