在染料敏化太陽能電池中，電子-電洞對是來自於染料受到光的激發後所產生，因此增加染料敏化太陽能電池的效能最有效的方法就是增加陽極之表面積及導電性，為了增加染料分子附著的量，本實驗不僅利用奈米碳管具有大表面積、良好導電性、化學穩定性佳、電子傳輸速率快之優點，且將奈米碳管以黃光微影製程將其作成方型陣列的形式，結合二氧化鈦奈米結構後，完成具有大表面積之陽極，本實驗之垂直配向奈米碳管陣列利用熱化學氣相沉積系統將其成長於不銹鋼基板上，隨後利用有機化學氣相沉積系統將二氧化鈦直接披覆於奈米碳管表面，垂直成長之奈米碳管陣列不僅增加二氧化鈦與基板間的導電性，同時方型陣列的形式亦增加了染料的吸附面積；此外亦將二氧化鈦以退火的方式去除Ti3+及氧缺陷，本研究以不同陣列大小及不同退火時間為參數，在陣列最佳化的實驗中，陣列大小為10: 10 m，陣列間距為10 m之奈米碳管陣列能達到最佳效能，利用退火去除二氧化鈦缺陷的實驗中，40分鐘的退火時間能夠有效的去除Ti3+缺陷。最佳光電特性之開路電壓(Voc)、短路電流密度(Jsc)、填充因子(FF)與光電轉換效率()分別為0.42 V、8.5 mA-cm-2、64%、3.3%.

n order to improve the photoelectric conversion efficiency (η) of dye-sensitized solar cells (DSSCs), the most effective method is to enhance the anode with electrical conductivity and usable surface area because electron-hole pairs are produced from the dye after illumination. Carbon nanotubes (CNTs) have many advantages such as a large surface area, good electric conduction, and good chemical stability. To increase the effective surface area of dye absorption, we combined vertically aligned CNTs bundle arrays with TiO2 nanostructures to fabricate an anode with a larger surface area. This study reports the synthesis of the vertically aligned CNTs bundle arrays on stainless steel sheets and the direct coating of TiO2 nanostructures on all the vertically aligned CNTs using thermal chemical vapor deposition (TCVD). The resultant vertically aligned CNTs bundle arrays not only serve as a template to provide good electric connection between theTiO2 nanostructures and the stainless steel sheet but also result in an increased surface area of TiO2 coating for dye absorption. In addition, an annealing process for TiO2 was achieved; the TiO2 annealing time related to the Ti3+ defect which would reduce the electron transport rate in a DSSC, the optimal annealing times of the anode were founded to be 40 min that promote the η of the DSSCs efficiently. We presented the optimum photoelectric characteristics as a short circuit current density (Jsc) of 8.5 mA, open circuit voltage (Voc) of 0.42 V, fill factor (FF) of 64%, and η of 3.3%.

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