摘要: | 染料敏化太陽能電池(Dye-Sensitized Solar Cells (DSCs))具有簡易製程及低製造成本等優點,是非常有應用潛力的新世代光伏電池技術。本研究針對實驗室開發之新型染料CYC-37及CYC-39進行元件組裝條件的優化以提高其光電轉換效率,除選擇使用Chenodeoxycholic acid (CDCA)與染料分子進行共吸附,以同步降低染料分子的聚集程度與填補裸露的TiO2表面,亦嘗試透過改變I-/I3-氧化還原對電解液的組成(含使用不同的Imidazolium iodide (如DMII、EMII與BMII)、不同濃度的LiI與4-tert-butylpyridine (tBP)),另有調整TiO2厚度、更改染料吸附溫度和時間,以及引入有機染料SBT6-A與CYC-37進行共敏化等。在AM 1.5G 模擬太陽光照射下,CYC-39敏化之元件經上述優化後的最佳短路電流密度(Jsc)、開路電壓(Voc)、填充因子(FF)與光電轉換效率分別為18.92 mA cm-2、0.694 V、70.56%及9.27%;在相同條件下,CYC-37敏化的電池亦可達相同性能(短路電流密度為18.74 mA cm-2,開路電壓為0.688 V,填充因子則為71.84%),兩者均優於Black dye元件效能(8.93%);在CYC-37與SBT6-A共敏化電池部份,SBT6-A補強了CYC-37於短波長吸收(400 ~ 550 nm)的不足,使元件Jsc可增加至20.27 mA cm-2,且光強度調制光電流(IMPS)測量結果亦顯示其元件的電子有效擴散係數(D)也亦高於單一染料敏化之電池元件,最終元件最高光電轉換效率達9.76%。;Dye-sensitized solar cells (DSCs) are the new-generation photovoltaic technologies, which have the advantages such as easy fabrication and low cost. In this study, we optimized the device fabrication conditions to improve power conversion efficiency (PCE) for our new ruthenium complexes sensitizers coded CYC-37 and CYC-39, respectively. In addition to utilizing chenodeoxycholic acid (CDCA) as a co-adsorbent for decreasing dye aggregation and reducing uncovered surface of TiO2 film, we changed the electrolyte composition based on iodide/triiodide (I-/I3-) redox couple, including different imidazolium iodide (BMII, DMII and EMII) as well as different concentration of LiI and tBP. Moreover, we optimized TiO2 thickness, adsorption tempareture and time, as well as the co-sensitization based on CYC-37 and an organic dye (SBT6-A). The best device sensitized with CYC-39 reaches Jsc, Voc and FF of 18.92 mA cm-2, 0.694 V and 70.56%, respectively, yielding PCE of 9.27%. Another device based on CYC-37 also provide the same PCE (the corresponding Jsc, Voc and FF is 18.74 mA cm-2, 0.688 V and 71.84%, respectively), both superior to that of Black dye (8.93%). In the co-sensitized device based on CYC-37 and SBT6-A, the latter dye increases device response in the region of 400 ~ 550 nm, yielding the highest Jsc of 20.27 mA cm-2 and PCE of 9.76%. The corresponding electron diffusion coefficient (D) estimated from the intensity- modulated photocurrent spectroscopy (IMPS) is also the highest among the devices sensitized with single dye molecule. |