本研究藉由調整反應溫度、時間、濃度、和攪拌，製備以水熱法成長的獨特四氧化三鈷(Co3O4)奈米結構，並將Co3O4奈米結構做為電洞傳輸層，且利用與一般固態染料敏化太陽能電池(Solid-State Dye-Sensitized Solar Cell，SS-DSSC)中膜層堆疊順序相反之製作方式，組成穩定、封裝容易的固態染料敏化太陽能電池。
目前本研究利用85 °C、24 hr、氨水體積百分濃度25%、磁石攪拌之製程條件，已成功地合成出表面帶有細微片狀結構之黑色Co3O4 nm多晶顆粒結構，其粒徑約為100 nm，而該奈米結構之能隙，經測定得知分別約為3.15 eV和1.85 eV。另外將所製備的Co3O4奈米顆粒以刮刀成型法塗佈，完成與一般SS-DSSC中膜層堆疊順序相反之元件，目的是使二氧化鈦(TiO2)層與Co3O4電洞傳輸層間有更佳之介面、使元件在陽光下有更好穩定性、使染料敏化電池之封裝更簡易。
在此研究中，雖然所製作之固態染料敏化太陽能電池的能量轉換效率僅只有2.6□10-4 %。然而經過分析，未來若繼續往增加Co3O4和TiO2間接觸面積、膜厚最佳化、及降低Co3O4奈米結構尺寸等方向努力，相信能製作出穩定、封裝簡易、且效率高之固態染料敏化太陽能電池。

In this work, through the optimization of temperature, time, concentration, and stirring of chemical the reaction, a hydrothermal synthesis of Co3O4 with unique nanostructure is presented. Using this nanostructured Co3O4 as a hole conductor, a solid-state dye-sensitized solar cell (SS-DSSC) with an inverse stacking sequence of layers is also fabricated.
The Co3O4 nanoparticles covered with smaller flakes have been synthesized in an aqueous solution with 25% of ammonia solution in the volume ratio, which is sealed at 85 °C for 24 hr. The as-grown Co3O4 black nanoparticles exhibit a diameter of around 100 nm, and optical band gaps of 3.15 eV and 1.85 eV. Besides, a SS-DSSC utilizing these as-grown Co3O4 nanoparticles as the hole collector with an inverse stacking sequence is fabricated by paste-squeegee method in order to provide better contact between hole Co3O4 conductor and TiO2 layer, higher stability under sunlight, and easier sealing condition than liquid-type dye-sensitized solar cells (DSSCs).
Even though the fabricated DSSC devices in this work exhibit low power conversion efficiency (PCE) of 2.6□10-4 %, major root causes were identified. Further efforts in improving the contact between Co3O4 and TiO2, optimizing the thickness of film stacks, and reducing Co3O4 nanostructure size will enable the fabrication of an SS-DSSC with good stability and power conversion efficiency.

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