利用一步法溶液製程開發高效能碳電極含鉛與無鉛鈣鈦礦太陽能電池

Abstract

本論文針對碳電極鈣鈦礦太陽能電池元件進行最佳化，其中包括純鉛 (CH3NH3PbI3) 以及無鉛 (CH3NH3SnIBr2(1-x)Cl2x) 兩種鈣鈦礦作為元件之吸光材料。首先為純鉛碳電極元件的優化，由於使用在碳電極系統之鈣鈦礦沉積手法有限，元件之光電轉換效率也因此難以提升，故本實驗室開發了慢速長晶法 (Slow Crystallization method, SC)，同時搭配鈣鈦礦前驅物之溶劑的挑選、元件長晶環境之溫溼度的控制、鈣鈦礦溶液濃度以及二氧化鈦多孔層厚度的優化，成功地提升元件之光電轉換效率，其平均效率為13.65±0.51 %，而最高效率可達14.96 %，且元件之長效穩定時間超過2000小時。 接著無鉛鈣鈦礦太陽能電池的部分，探討了不同鈣鈦礦前驅物之溶劑對無鉛鈣鈦礦元件效率的影響，並優化二氧化鈦多孔層的厚度，接著討論了不同元件燒結溫度對鈣鈦礦結晶狀況的影響，最後我們調整SnBr2及SnCl2間的比例，將CH3NH3SnIBr1.8Cl0.2無鉛鈣鈦礦運用於碳電極系統，成功地將元件之光電轉換效率提升至2.84 %。

In this thesis, we focused on performance optimization for carbon-based mesoscopic perovskite solar cell, including pure lead (CH3NH3PbI3) and lead-free (CH3NH3SnIBr2(1-x)Cl2x) perovskite as light-absorbing material. The first part is carbon-based solar cells with lead perovskite. Because the technology of perovskite is limited in carbon-based solar cells, and that lead to poor efficiency. So our lab developed Slow Crystallization method. By selecting solvent of perovskite precursors, controlling surrounding temperature and humidity, tuning concentration of perovskite solution and optimizing TiO2 thickness, we successfully improved efficiency to 13.65±0.51 % and best one reach 14.96 %. The device efficiency keeps on 13 % without encapsulation under air atmosphere at room temperature more than 2000 hours. In other hand, we discussed lead-free perovskite solar cell. At first, we investigated different solvent that influence on device efficiency and then optimized TiO2 thickness. After that, we compared crystallization of perovskite with different annealing temperature. Finally, we controlled SnBr2 /SnCl2 ratio and successfully improved efficiency to 2.84 % by using CH3NH3SnIBr1.8Cl0.2 in carbon-based mesoscopic perovskite solar cell.