本研究是利用自我組裝單分子層(SAM)：MPTMS，來修飾TiO2光電極的表面以應用於CdSe量子點敏化太陽能電池。結果發現，提供化學浴沉積法 (CBD) 沈積 CdSe的三種不同陰、陽離子濃度(0.5M、0.1M、0.05M) 與CBD層數中，以 0.05M 的離子濃度以及五層的CBD層數能達到較佳的光電轉化效率，其在TiO2/CdSe(5) 以及 TiO2/MPTMS/CdSe(5) 的效率分別為1.5和1.8%。由紫外光-可見光光譜圖和暗電流的結果可知，經過 SAM 修飾過的電極，其有較高的吸光強度以及較小的暗電流。這是因為 SAM 能提高CdSe 在TiO2 薄膜表面的覆蓋率與沉積量，降低 TiO2 與電解質接觸的面積，以抑制電荷再結合的機率，因而提昇光電轉化效率。此外，本研究也於CdSe量子點外部組裝一層很薄的硫化鋅 (ZnS) 以減少電池漏電流的發生，使TiO2/MPTMS/CdSe(5)/ZnS 光電池的效率能提升至2.29%。最後，以 300℃ 對光電極進行熱處理來提高 CdSe 量子點的結晶性，並減少光電極界面的缺陷，以提高電池的光電流。此方法能使TiO2/MPTMS/CdSe(5)/ZnS/post-heated光電池達到2.65% 的最佳效率。

In this study, self-assembly monolayer (SAM), 3-mercaptopropyl trimethoxysilane, is used to modify the surface of TiO2 electrode for a CdSe quantum dots (QDs)-sensitized solar cell. The results show that the three various concentration (0.5M、0.1M、0.05M) of ions for the deposition of CdSe by chemical bath deposition (CBD) and the CBD layers, 0.05M ions concentration and CBD five layers can obtain the highest energy conversion efficiency. For TiO2/CdSe(5) and TiO2/MPTMS/CdSe(5), the efficiency is 1.5 and 1.8%, respectively. From UV-vis spectra and dark current result, the SAM-modified cell displays a higher absorbance and a lower dark current. It is because SAM shows a better coverage and a higher incorporated amount of CdSe. This can reduce the contact area between TiO2 and electrolyte, inhibiting the charge recombination and enhancing the efficiency. Here, a thin ZnS film is also used as a passive layer to assembly on the CdSe QD to decrease the leakage current of the cell. The efficiency of this cell, TiO2/MPTMS/CdSe(5)/ZnS, can be improved to 2.29%. In order to increase the photocurrents of the cell, a further post-heated annealing process was carried out. An energy conversion efficiency of 2.65 % is achieved using a TiO2/MPMTS/CdSe/ZnS/post-heated electrode, under the illumination of one sun (AM 1.5, 100 mW/cm2).

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