Investigation of Efficient and Semitransparent Organic Solar Cells with Inverted Structure

高效率且半透光之反相有機太陽能電池製程研究

李智聖(Jhih-Sheng Lee)

指導教授 ： 洪勝富 ； 孟心飛

國立清華大學/電機資訊學院/電子工程研究所/碩士(2008年)

https://doi.org/10.6843/NTHU.2008.00697

摘要

無機太陽能電池儘管效率已達24.7%，多層結構更將近34%，但是矽原料短缺、製程機台昂貴且複雜，成本因此居高不下，對於商業應用實有困難。有機共軛高分子太陽能電池不僅製程簡單、成本低廉，因具備可撓特性，元件可隨著空間作形狀變化；噴墨印刷及刮刀的技術更可以將元件朝向大面積、大尺寸發展，以上優點都使得此第三代太陽能電池在未來的發展上極具潛力與想像空間。
我們以氧化物—碳酸銫 (Cs2CO3) 與三氧化鉬 (MoO3) 分別作為電子與電洞的注入層，並且藉此與ITO及金屬接觸後產生一電偶極 (Dipole) 因而調變陰陽極功函數使元件成反相結構；主動層材料我們採BHJ系統，以P3HT混合PCBM於鄰-二氯苯 (DCB)，利用旋轉塗佈的方法在ITO基板上成膜。
本論文藉由各種條件的調變以得到高效率元件，並且，由於元件的電極單薄 (10nm~20nm)，因此同時具備光穿透的能力。最終我們得到最佳效率近3.7% (銀電極)；而金為電極時效率為2.84%，金屬面照光仍有1.8%，光波長在650nm~850nm穿透率達50%~65%。如此光穿透能力對於未來『多層結構』的製作上是我們獨有的優勢，發展空間也因而有更多的選擇性。

關鍵字

反相太陽能電池 ； 反結構 ； 有機太陽能 ； 碳酸銫 ； 三氧化鉬 ； 半透明

並列摘要

Although the efficiency of inorganic solar cells have been reached 24.7% and even 34% for tandem cells, it is not suitable for commercial application due to its high cost. Much more attention has been put to organic solar cells due to its simple and cost-effective fabrication process. Furthermore, flexible substrates and the potential to scale up to large area make it a promising alternative to silicon-based solar cell.
In our study, cesium carbonate (Cs2CO3) and molybdenum oxide (MoO3) have been used as electron- and hole- transport layers. Besides, they also change work function of ITO and metal electrode by forming a thin dipole layer. A bulk heterojunction BHJ consisting blending of P3HT and PCBM in 1, 2-Dichlorobenzene spin-coated on ITO-coated glass is used as our active layer. For device with silver as cathode, the best PCE we studied is almost 3.7%. For device with gold as cathode, we have 2.8% for glass-illumination and 1.8% for metal-illumination. Further, Transmittance is up to 50%~65% within the spectrum from 650nm to 850nm. It would be our specific predominance and make us have more thoughts and choices to fulfill highly-efficient tandem cells.

並列關鍵字

inverted solar cell ； organic solar cell ； photovoltaic ； semitransparent ； HASH(0x1d705f40) ； HASH(0x1d705fe0)

參考文獻

[1] K. M. Coakley,Wudl and M. D. McGehee,“Conjugated polymer photovoltaic cells,” Chem. Mater. 16, 4533 (2004).

[2] Harald Hoppe, and Niyazi Serdar Sariciftci,“Organic solar cell: An review,”J. Mater. Res., Vol. 19, No. 7, Jul 2004.

[3] C. W. Tang, “Two-layer organic photovoltaic cell,” Appl. Phys. Lett. 48, 183 (1986)

[5] G. Yu, K. Pakbaz, and A. J. Heeger,“Semiconducting polymer diodes: Large size, low cost photodetectors with excellent visible-ultraviolet sensitivity,”Appl. Phys. Lett. 64, 3422 (1994).

[8] C. Melzer, E. J. Koop, V. D. Mihailetchi, and P. W. M. Blom, Adv. Funct. Mater. 14, 865 (2004)